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OAK RIDGE #ATIONAt LABORATORY opetrated by

~ CARBIDE l ~CORPORATION ~ NUCLEAR DlVfSlON for the

US. ATOMIC EMEROY COMMlSStON ORNL- TM- 91 1

R, H Guymon P. N. Haubenreich J.R. Engel

TH;?

r”91hb.’.

I ~ P~ PCLU S t Rq”ZV!ED. n ~ , I:T

NOTICE This document contains information of a prelimlnary nature and was prepared primarily for internal use at the Oak Ridge Notionol Loboratory. I t is subject to revision or correction ond therefore does not represent o final report.

â&#x20AC;&#x2DC;

l L This report was preparod as an account of Government spansorod work.

Neithor the United States,

nor the Commission, nor any person acting an behalf of the Commission:

A. Makes any warranty or reprosentation, axpessod or implied, with respect to tho accuracy, complateness, any

or usofulners of th. information contained i n this raport, or that the

information,

apparatus,

US.

method, or procors disclosed i n this report may not infringo

privately ownod rights; or

Assumes

any liabilities with respect t o the use of, or for damages resulting from the us6 of

any information, apparatus, mothod,

procoss disclasod i n this report.

As usad in th. above, â&#x20AC;&#x153;porson acting an behalf of tho Commissionâ&#x20AC;? contractw of the Commission,

includor any employoe or

omployee of such contractor, to tho extant that such amployee

or contractor of tho Commission, or omployae of such contractor proparos, disseminates, or provides accoss to, any information pursuont t o his employment or contract with the Commisaion,

or h i s omploymont with such contractor.

MSRE DESIGN A?FiDOPERATIONSREPORT Part XI TEST E'ROGRAM

R. H. Guymon P. N. Haubenreich J. R. Engel

OAK RIDGE NATIONAL LABORATORY Oak Ridge, Tennessee operated by UMION CARBIm CORPORAT'LON for the U.S. ATOMIC ENERGYCOMMISSION

iii

rrcr

PREFACE This r e p o r t i s one of a serSes t h a t describes t h e design and operat i o n of the Molten-Salt Reactor Expertmeat. below.

ORNLt-TM- 728

A l l the reports a r e l i s t e d

MSRE Design and Operations Report, P a r t I, Descriptio2 of Reactor Design by R . C . Robertson MSRE Design and Operations Report, P a r t 11, Nuclear and Process Instrunentation, by J . R . Tallackson

ORNL-TM-730

MSRE Design and Operations Report, P a r t 111, Nuclear Analysis, by P. N. Haubenreich and J . R . Engel, B. E. Prince, and H. C . C l a i b o r m MSRE Design and Operations Report, Part LV, Chemistry and Materials, by F. F. 3iankenship and A . Taboada

OFNL- TM-732

MSRE Design and Operations Report, P a r t V, Reactor S a f e t y Analysis Report, by S E Beall, P. N. Haubenreich, R . B. Lindauer, and J. R. Tallackson e

ORNL-TM-733

ORNL-TM- 907

C,RML-m-go8

ORLNL- TM-go9

OmL-TM-910

3c*

.MSRE Design and Operations Report, Part VI, Operatlng L i m i t s , by S. E. B a l l a%d R. H. Guymon

MSFE Design and Operations Report, P a r t VZL, File1 Handling and Processrimg Plant, by R . B. Lindauer MSF3 Design and Operations Report, Part vE3, Operating Procedures, by R E:. Guymon

MSRE Design and Operations Report, P a r t IX, Safety Procedures and Emergency Plans, by A . B. Smith

MSRE Design and Operations Report, P a r t X, Maintenance Equipment a i d Procedures, by E . C. Hise a r d R. Bluqberg

These r e p o r t s w i l l be the l a s t i z t h e s e r i e s t o 'oe puUiehed.

iv v1

ORNL-TM- gii*

MSRE Design and Operations Report, P a r t X I , Test Program, by R . H. Guymon, P. N. Haubenreich, and J . R . Engel MSRE Design and Operations Report, Part X I I , L i s t s : Drawings, S p e c i f i c a t i o n s , Line Schedules, Instrument Tabulations (Vol.1 and 2)

FOREWORD

The reader of t h i s r e p o r t should be aware t h a t t h e date of i s s u e i s somewhat misleading

- this

d e s c r i p t i o n of t h e MSâ&#x201A;ŹB t e s t program was

w r i t t e n before t h e f a c t and has not been updated. document began i n 1964 and continued through

Preparation of t h i s

1965, each

s e c t i o n being

issued i n d r a f t form as it was completed and before operations e n t e r e d t h a t phase of the program.

I n e v i t a b l y some s i t u a t i o n s arose ( t h e offgas-

system troubles, f o r example) t h a t added some tests a n d some time t o the planned program.

No major deviation from the broad o u t l i n e has occurred,

however, and we b e l i e v e it worthwhile t o i s s u e t h i s r e p o r t as a convenient record of what was planned f o r t h e MSRE.

For an account of what a c t u a l l y

transpired, the reader should t u r n t o the Molten S a l t Reactor P r o j e c t semiannual progress r e p o r t s .

vii CODTENTS 1.

Paffe

INTRODUCTION

1-1

1.1

................................................... OBJECTIVES .................................................

1-1

1.2

AREAS TO

BE INVESTIGATED ...................................

1-1

............................ 1 - 1 1.2.2 Engineering ........................................ 1-2 1-2 1.2.3 Reactor Physics .................................... 1 . 3 PHASESOF PROGRAM ......................................... 1-3 1.4 NCTJMENTATION ............................................. 1-4 2. NO"IJCjJjAR TESTING ............................................. 2-1 2 . 1 OBJECTIVES ................................................ 2-1 2-1 2.2 EXPLANATION OF PROCEWRES .................................. 2-2 2.3 PROCEDURES ................................................. 2.3.1 Fuel System ....................................... 2-2 2.3.2 Fuel-Drain-Tank System ............................ 2-5 2-7 2.3.3 Coolant System .................................... 2.3.4 Coolant Pain-Tank System ......................... 2-10 2-11 2.3.5 Cover-Gas and Offgas Systems ...................... o i l Systems ........................................ 2-12 2.3.6 2.3.7 Chemical Processing System ........................ 2-13 2-14 2.3.8 Leak-Detector System ............................... 2.3.9 Cooling-Water Systems ............................. 2-15 2-16 2.3.10 Component-Cooling Systems ......................... 2.3.11 Instrument-Air and Auxiliary-Air Systems ........... 2-17 2.3.12 Instrumentation .................................... 2-18 2.3.13 E l e c t r i c a l System .................................. 2-20 2.3.14 S h i e l d and Containment ............................ 2-21 2-23 2.3.15 V e n t i l a t i o n System ................................ 2.3.16 Liquid-Waste System ................................ 2-24 2-25 2.3.17 Samplers .......................................... 2-25 2,3.18 Control Rods ....................................... 2-26 2.3.19 Heaters ........................................... 1.2.1

Chemistry and Materials

viii

..................................... 2-27 2-27 2.3.21 Miscellaneous ..................................... 2.3.22 E n t i r e P l a n t ...................................... 2-28 3 . ZERO POW2 EXPERIMENTS ......................................... 3- 1 3.1 OBJECTIVES ................................................ 3- 1 3.2 PROCEDURES ................................................ 3- 2 3- 2 3.2.1 I n i t i a l C r i t i c a l Experiment ........................ 3.2.2 C a l i b r a t i o n of Control Rods ........................ 3- 4 3.2.3 Evaluation of Nuclear Parameters .................. 3- 8 2.3.20

3.2.4 3.2.5 3.2.6

Freeze Valves

................... 3- 9 Evaluation of Neutron Sources and Future Requirements of t h e E x t e r n a l Source .............. 3-14 Preliminary Studies of Dynamics

Chemical Analyses

.................................

3-15 4- 1

......................................... ................................................ 4- 1 4.2 PROCEEURES ................................................ 4- 2 4.2.1 Shielding and Containment Surveys ................. 4- 2 4.2.2 C a l i b r a t i o n of Nuclear-Power Instruments .......... 4- 4 4.2.3 Power C o e f f i c i e n t of R e a c t i v i t y ................... 4- 7 4.2.4 Xenon Poisoning ................................... 4- 8 4.2.5 On-Line Analysis of Operation ..................... 4- 9 Establishment of B s e l i n e for Chemical Analyses .... 4-12 4.2.6 4-13 4.2.7 Intermediate Dynamics S t u d i e s ..................... 5 . REACTOR CAPABILITY INVESTIGATIONS - APPROACH TO FULL POWER ..... 5- 1 5.1 OBJECTIVES ................................................ 5- 1 5.2 PROCEDURES ................................................ 5- 2 5.2.1 Performance of Control Systems .................... 5- 2 5.2.2 Shielding and Containment Adequacy ................ 5- 3 5.2.3 C a l i b r a t i o n of Power Instruments .................. 5- 4 Xenon Poisoning ................................... 5- 5 5.2.4 5.2.5 On-Line Analysis of Operation ..................... 5- 5 5.2.6 Thermal E f f e c t s of Power Operation ................ 5- 6 5.2.7 C a p a b i l i t y and Performance of Heat Transfer Systems ......................................... 5- 7 4

LOW POWER MEASUREME-IITS 4.1 OBJECTIVES

................ 5.2.9 Dynamics Studies .................................. SYSTEM CAPABILITY INVESTIGATIONS - EXTENDED OPERATION .. . 5.2.8

Chemical E f f e c t s of Power Operation

................................................ 6- 1 ................................................ 6- 2 ..................................... 6- 2 6- 2 Materials Cornpatability ............................ Changes i n Dynamics ................................ 6- 5 Performance of Components and Equipment ............ 6- 5

6.1 OWECTIVW 6.2 PROCEDURES 6.2.1 m e 1 Chemistry 6.2.2

6.2.3 6.2.4

5- 8 5- 9 6- 1

SECTION l I,TRODUCTION

1.1 OBJECTIVES The purpose of t h e Molten S a l t Reactor Experiment, s t a t e d broadly,

i s t o demonstrate t h a t many of t h e d e s i r a b l e f e a t u r e s of molten s a l t rea c t o r s can p r e s e n t l y be embodied i n a p r a c t i c a l r e a c t o r which can be operated s a f e l y and r e l i a b l y , and can be serviced without undue d i f f i c u l t y .

T3.e program which has been l a i d out f o r t h e MSRE i s intended t o provide t h a t demonstration i n a safe, e f f i c i e n t and conclusive manner. .!!though t h e complete success of t h e E R E depends i n p a r t on t h e r e a c t o r being a b l e t o operate f o r long periods a t f u l l power, t h e t e s t program recognizes t h a t t h e success of a r e a c t o r experiment i s not measured s o l e l y i n megawatt-days.

The t e s t s and t h e experiments a r e

designel! t o be p e n e t r a t i n g and thorough, s o t h a t when t h e experiment i s concluded not only w i l l r e l i a b l e operation and reasonable maintenance have been demonstrated, b u t t h e r e will be as many conclusive answers a s p o s s i b l e t o t h e important qaestions p e r t a i n i n g t o t h e p r a c t i c a b i l i t y of molten s d t r e a c t o r s of t h i s general type. 1.2

1.2.1

AREAS TO BE INVESTIGATED

Chemistry ar?d Materials Some of t h e most important questions have t o do with tk?e behavior

a i d i n t e r a c t i o n s of t h e f u e l salt, t h e graphite, and t h e container

m a t e r i a l i n t h e r e a c t o r environment.

The major p o i n t s t o be i c v e s t i g a t e d

i n t h i s area a r e : 1.

fuel stability,

p e n e t r a t i o n of t h e g r a p h i t e by Yule f u e l salt,

g r a p h i t e damage,

4. 5. 6.

xenon r e t e n t i o n and removal, corrosion, behavior of corrosion products and non-volatile f i s s i o n products. 3 e p r i n c i p a l means of i n v e s t i g a t i o n used d;lring operation w i l l be

regillar sampling and chemical a n a l y s i s of t h e fuel salt, a n a l y s i s of t5e

1-2 long-term r e a c t i - J i t y behavior, a3d determination of t h e i s o t o p i c compos i t i o n of t h e xenon i n t h e offgas.

Periodically, during shutdowns, s p e c i -

mens of g r a p h i t e and of INOR w i l l be removed from t h e core for examination. Ehgineering

1.2'. 2

The MSRE incorporates some novel f e a t u r e s and components which have been developed and designed s p e c i f i c a l l y f o r molten s a l t r e a c t o r s .

The

t e s t program w i l l o b t a i n performance d a t a on t h e s e i t e m s , permitting evalnation of ideas and p r i n c i p l e s which could b e employed i n f u t u r e reactors. The broad heading of lbgineering a l s o covers t h e extensive s t a r t - u p program which must be devoted t o t h e checkout, c a l i b r a t i o n and preliminary t e s t i n g of t h e many more or less conventional devices and systems i n t h e MSRE.

1.2.3

Reactor Physics From t h e standpoint of r e a c t o r physics, t h e MSRE core i s uniqne.

But t h e nuclear design posed no s e r i o u s problems.

One reason f o r t h i s

apparent paradox i s t h e s i m p l i c i t y of t h e core, which makes simple s p a t i a l approximations v a l i d .

Another i s t h a t t h e demands f o r accuracy i n t h e

p r e d i c t i o n s a r e not severe.

This follows because t h e f u e l i s f l u i d ,

pe-mitting easy adjustment of t h e uranium loading and e l i m i n a t i a g h o t s p o t problems a s s o c i a t e d with h e a t t r a n s f e r from f u e l t o core coolant.

For t h e s e reasons t h e design d i d not employ e x t r e n d y s o p h i s t i c a t e d c a l c u l a t i o n a l procedures and t h e r e were no preliminary c r i t i c a l experimects.

Instead, t h e physics p a r t of t h e r e a c t o r t e s t program i s r e l i e d

on t o provide such accurate information on nuclear c h a r a c t e r i s t i c s as may be required. The program of Teactor physics measuremects begins with t h e experimental loading of uranium t o a t t a i n c r i t i c a l i t y .

Followirig t h i s w i l l be

experiments t o v e r i f y t h a t t h e system i s s t a b l e and safe.

Accwate

measurements of rod worth and r e a c t i v i t y c o e f f i c i e n t s w i l l be made t o f a c i l i t a t e l a t e r a m l y s i s of t h e r e a c t i v i t y behaTJior during power operation.

This a n a l y s i s w i l l be concerned, among o t h e r things, with t h e

t r a n s i e n t behavior of 135Xe.

The r e a c t i v i t y behavior w i l l a l s o be

scrdtiriized f o r p o s s i b l e anorrialies, which might i n d i c a t e changes conditions w i t h i n t h e core.

l.3

PHASES OF PROGRAM

The t e s t i n g and experimental operation of t h e E R E f a l l n a t u r a l l y i n t o d i f f e r e n t phases which must follow in sequence.

precritical testing,

i n i t i a l c s i t i c a l measurements,

low-power measurements,

reactor capability investigations.

They are:

The p r e c r i t i c a l t e s t i n g phase begins with t h e new operators, as p a r t of t h e i r t r a i n i n g , checking t h e l o c a t i o n of equipment and comparing t h e i n s t a l l e d piping a g a i n s t t h e flowsheets.

As systems aLre completed,

l e a k t e s t i n g , purging, f i l l i n g , c a l i b r a t i n g and t e s t operation a r e started.

The p r e c r i t i c a l t e s t i n g culminates i n shakedown operation of t h e

e n t i r e r e a c t o r system, with f l u s h salt i n t h e f u e l systern and coolant

s a l t i n t h e coolant system. I n t h e i n i t i a l c r i t i c a l experiments, f u e l salt will be loaded a2d enriched uranium w i l l be added i n increments t o b r i n g t h e concentration up t o t h a t required f o r operation.

During t h i s phase t h e c o n t r o l rods

w i l l be c a l i b r a t e d and f u e l concentration, temperature and pressure

c o e f f i c i e n t s of r e a c t i v i t y w i l l be measured.

Baseline d a t a on t h e

f u e l chemistry and corrosion w i l . 1 a l s o be obtained during t h i s period. Following t h e c r i t i c a l experiments, which w i l l be conducted a t a f e w w a t t s of nuclear power, t h e powe:? will be r a i s e d t o p e n n i t c e r t a i n

tests.

These w i l l include t e s t s of t h e nuclear power servo con%rol

system, t h e automatic l o a d c o n t r o l system, t h e c a l i b r a t i o n of power i n d i c a t o r s and surveys of t h e b i o l o g i c a l shielding.

The w c l e a r power

w i l l be l e s s t h a n 2 Mw during t h i s period.

Capability i n v e s t i g a t i o n s c o n s i s t of two p a r t s :

Tlze f i r s t , a s t e p -

wise approach t o f u l l power; t h e second, extended operation.

During t h e

approach t o f u l l power, temperatures, r a d i a t i o n l e v e l s and t h e nuclear power noise w i l l be observed t o determine i f any ul?$oreseen condition e x i s t s which would r e s t r i c t t h e a t t a i n a b l e power l e v e l .

Extended opera-

t i o n will t e s t t h e c e l i a b i l i t y of eqxipment and long-term corrosion a d I c

f i s s i o i - p r o & u c t behavior.

Maintenance w i l l be c a r r i e d o J t as req%ired

and t h e r e a c t o r w i l l be shdt, down p e r i o d i c a l l y f o r removal of samples

1-4

4â&#x20AC;&#x2122; from t h e core.

Long-range-plans i n c k - d e ckemical processing of t h e f u e l

s a l t and operation w i t 5 d i f f e r e n t f u e l s a l t compositions.

!his r e p o r t describes, i n r a t h e r general terms, t h e experiments t o be performed wit5 some d i s x s s i o n of t h e methods t o be used and t h e type of r e s u l t s expected.

It provides t h e b a s i c p l a n f o r t h e day-to-day

experimental program. Each experiment or t e s t , p r i o r t o i t s performance, i s t h e s u b j e c t of a Test Memo which describes t h a t p a r t i c u l a r experiment i n complete detail.

A stepwise procedure with r e f e r e n c s t o applicable e s t a b l i s h e d

operating procedures i s included.

If they are reqidired, supplementary

check l i s t s and sample data sheets a r e made a p a r t of t h e Test Memo. The Test Memos mast be i n t e r n a l l y reviewed and approved before the? experiment i s performed.

Since t h e procedural d e t a i l s a r e of l i m i t e d

interest;, t h e s e documents a r e d i s t r i b u t e d only t o personnel and superv i s i o n d i r e c t l y connected with t h e experiment. A s soon as possible a f t e r t h e completion of an experiment, a T e s t

Report i s w r i t t e n t o describe t h e r e s u l t s .

This r e p o r t summarizes t h e

t e s t experience and data obtained and presents any conclusions t h a t can be drawn.

The scope and importance of t h e i n d i v i d u a l experiments d e t e r -

mine %he na72re and d i s t r i b u t i o n of tLe T e s t Reports.

SECrnION 2

2.1

03JECTIVES

P r i o r t o f u l l - s c a l e operation t h e ,WRE w i l l undergo a number of shakedown runs and tests.

The purposes are:

t o a s s u r e t h a t t h e design i s adequate and t h a t t h e eqixlpment and instrumentation function as designed;

t o o b t a i n information which may be needed f o r fu-ture operation o r a n a l y s i s of t h e r e a c t o r ( c a l i b r a t i o n of instruments and equipment, dimensional changes, e t c . ) ;

t o discover and c o r r e c t weak p o i n t s of t h e system t o a s s u r e t 3 a t it i s safe and operable (This includes long term i n t e g r a t e d runs t o allow f o r e a r l y f a i l u r e of defective equipmert ) ;

t o develop sampling techniques and determine t h e adeq?.-acy

of a n a l y s i s

procedures;

t o t r a i n operating personnel and check out t h e operating procedures;

t o determine t h e e f f e c t s of equipment o r instrument f a i l u r e s o r maloperati on. 2.2

EXPLANATION OF PROCEXURES

Most of t h e nonnuclear t e s t s w i l l be performed before t h e r e a c t o r i s made c r i t i c a l f o r t h e f i r s t t i m e .

EIowever, t h e t e s t i n g of some

equipment w i l l be completed a t a l a t e r d a t e .

For example, t h e vapor-

condensing system and t h e f i n a l closure of t h e containment v e s s e l w i l l not be completed before t h e c r i t i c a l experiment s o t h e t e s t i n g of t h e s e

items w i l l be performed a f t e r t h e zero-power nuclear tests.

Thus, t h e

order i n which t h e t e s t s are l i s t e d does n o t i n d i c a t e t5e chronological order of t e s t i n g . Because of t h e l a r g e number of

nonnuclear tests, a ndmbering system

w a s adopted t o f a c i l i t a t e t h e maiztenance of reaords.

The various t e s t

memos and operating procedmzs t h a t am applicable are r e f e r r e d t o by V

number i n t h e descrip5ions whicn follow.

2-2

2.3 PROCEMjRlFX Fuel System

2.3.1

'The f u e l system c o n s i s t s of t h e reactor, t h e f u e l pump, t h e overflow tank, t h e h e a t exchanger, and a s s o c i a t e d piping. 2.3.1.1

I ni ti al 3eatu-p --

P r i o r t o and during e a r l y heatups, t h e f u e l system and g r a p h i t e w i l l be purged of moisture.

The necessary h e a t e r s e t t i n g s f o r various average

system temperatures will be determined along with temperature gradients, cool down rates, and adequacy of spring piping supports. Purge

- Oxygen

and moisture must be removed from t h e sys-kem p r i o r

t o heatup or a d d i t i o n of s a l t t o t h e system.

This will be done by evacu-

a t i n g and r e f i l l i n g t h e system with helium.

The system w i l l be evacuated

through a temporary connection t o l i n e 110 i n t h e drain-tank c e l l .

Since

t h e r e w i l l be no s a l t i n t h e f r e e z e valves a t t h i s time, t h e e n t i r e d r a i n tank system i s purged a l s o .

Since a l a r g e q u a n t i t y of moisture i s

expected t o be r e l e a s e d from t h e g r a p h i t e during heatup, t h e moisture content of t b e helium w i l l be monitored and f u r t h e r evacuations performed during heatup i f necessary.

Although evacxation w i l l be from l i n e 110

a t t h e drain-tank c e l l , t h e venting of purge helium w i l l be through t h e offgas systeni charcoal beds.

Details are given i n T e s t Memo XI 2.3.1.1-A.

Heater S e t t i n g s - During e a r l y heatups, a11 t h e r e a c t o r - c e l l piping

will be heated concurrently.

A t l e a s t t h a t p o r t i o n of t h e c o o l a n t - s a l t

system i n t k e r e a c t o r c e l l must be keated conczrrently due t o thermal expansion of piping.

Thermocozpies w i l l be monitored and excessive

tl.=ermal gradients, s x h as might occur a t t h e c e l l penetrations, w i l l be minimized by proper h e a t e r adjxstnent.

Heater-control settings w i l l

be detemiEed f o r holding t h e system a t various temperatures.

The rate

of cooldown and temperature g r a d i e n t s during a simulated power outage w i l l be checked.

Details are given i n T e s t Memo XI 2.3.1.1-B.

Thermal S t r e s s i n Piping and Eq-Jipment -The

thermal growth of t h e

piping system and t h e o p e r a t i o r of t h e fuel-pump and p i p i n g supports w i l l be r,oted during hea%up. !2e piping h e a t e r s w i l l be observed while

a t operating t e m p e r a t x e t o d e t e c t any apparent d i f f i c u l t i e s due t o t h e

expansion of t h e piping system.

Temperature g r a d i e n t s a t p o i n t s of

stress w i l l be analyzed and s t r a i n gages w i l l be used i f necessary. Details are given i n T e s t Memo X I 2.3.1.1-C.

-I n-i t-i a-l -F i-l l-and - -(Qeration --During t h e i n i t i a l fill, t h e normal * VIII, Operating Procedures, w i l l be

2.3.1.2 Part

as suck, w i l l be taken.

f i l l procedure, Section 51.9 used and no c a l i b r a t i o n data,

S a l t w i l l be c i r c u l a t e d and sampled f o r a

p e r i o d t o g a i n both operating experience and continuous-operation sample data.

The system w i l l then be drained and r e f i l l e d during which t h e

system w i l l be c a l i b r a t e d vs t h e amount of s a l t added, rate of f i l l determined, overflow tank c a l i b r a t e d , cooling t e s t s performed and d r a i n t i m e established. Calibration

- During

t h e c a l i b r a t i o n f i l l , t h e fuel-system level.

vs t h e amount of s a l t added as t h e draLcand volume w i l l be c a l i b r a t e d tank p r e s s u r e i s increased by increments.

After each p a r t i a l a d d i t i o n

t h e approximate l e v e l i n t h e system and weight of s a l t i n t h e d r a i n tank w i l l . be determined.

From previously obtained drain-tank c a l i b r a t i o n s

t h e weight of s a l t i n t h e f u e l system vs e l e v a t i o n w i l l be p l o t t e d .

The

f u e l pump w i l l be o v e r f i l l e d t o determine t h e l o c a t i o n of t5e overflow inlet.

Some salt w i l l be t r a n s f e r r e d t o t h e overflow t a &

l e v e l indicators.

test the

Details are given i n Test Memo X I 2.3.1.2-A.

Fuel-Pump Tests -The

tests t o be performed on t h e f u e l pump i n -

clude checking operation of t h e bubble-tube l e v e l i n d i c a t o r s and determination of l o a d and no-load power requirements of t h e fuel-pump m o t x . Details are a l s o given i n T e s t Memo X I 2.3.1.2-A.

Cooling Rates

- Cooling

rates f o r both t h e coolant and f u e l systems 0

w i l l be determined from a s t a r t i n g condition of 1200 F t o a mininum of

1000째F.

Recorder c h a r t s and photographs of scanner t r a c e s w i l l be used

t o determine cold s p o t s and cooling rates.

Details are given i n Test

Memo X I 2.3.1.2-C. *R. H. Guymon, MSFE Design and Operations Report, P a r t VIII, Operating O a k Ridge National Laboratory, Procedures, USAEC Report ORNL-TM-908, l\ovembex, 1965.

2 -4

4 Drain Times - Drain t i m e s w i L . be determined a t both m i n i m a and

maximum circumstances - t h e drain-tank vent open. I n i t i a l Operation

slowest d r a i n t i m e being t h a t with only t h e

Details a r e given i n Test Memo X I 2.3.1.2-A.

- T1-e preliminary

f i l l w i l l be done according t o

a normal f i l l procedure wkicr includes t h e f r e e z i n g of a salt plug i n t h p r e a c t o r access nozzle.

The system w i l l be f i l l e d , t h e f r e e z e valve

f n z e c , and s a l t c l r c - d a t i o r , begun.

C i r c u l a t i o n and normal operating

conditions w 9 - l be e s t a b l i s h e d f o r a p e r i o d of days during which salt samples f o r chemical a n a l y s i s w i l l be withdrawn from t h e f u e l p u p 3hrough a temporary sampler.

D e t a i l s of t h e preliminary f i l l are given

i n Section 51, P a r t VIII, Operating Procedures.

2.3.i.3

-ton -

--InLeetion ---

Calculation of a r e a c t i v i t y balance a t frequent i n t e r v a l s provides

a valuable i n d i c a t i o n of conditions i n t h e core daring nuclear opera+' "lo=. Whenever t h e power i s s i g n i f i c a n t (above a f e w k i l o w a t t s ) , t h e poisoning of 13'Xe

i s an important term i n t h e r e a c t i v i t y balance.

Constants whick

are used i n t h e computation of t h e 135Xe poisoning must t h e r e f o r e be

a v a i l a b l e a t t h e o u t s e t of nuclear operation. The 135Xe

poisoning depends s t r o n g l y on t h e amount of gas bubbles

c i r c u l a t i n g with t?ie salt, t h e s t r i p p i n g i n t h e pump bowl and t h e mass t r a n s f e r of xenon between t h e s a l t and t h e g r a p h i t e i n t h e core.

e f f e c t of t h e s e meckanisms can be p r e d i c t e d from thee-ry, b a s i c data and pLurrp-loop experiments, b u t t h e uncertairM.es are undesirably l a r g e . Therefore, during t h e p r e c r i t i c a l t e s t i n g an experiment w i l l be done witk r a d i o a c t i v e k-rypton t o proxi.de f u r t h e r information on t h e behavior of noble gases i n t h e MSRE. Radioactive 8E;-Kr (10.4 y half-lice) will be i n j e c t e d with t%e helium f l o w i n t o the f d e l p u q while f l u s h s a l t i s being c i r c u l a t e d . The offgas i s diverted, j u s t a f t e r l e a v i n g t3.e p.xx bowl, p a s t a r a d i a t i o n measuring device.

Sampling connections f o r t r a p p i n g krypton on

charcoal are a l s o provided a t t3.k p o i n t .

Normally t h e flow bypasses

t h e sampling bombs, Back i l l t o %e offgas l i n e , through t h e charcoal. beds and up t k e v e n t i l a t i w s5ack. B a s i c a l l y t h e experiment c o n s i s t s of s a b r a t i n g t h e sal.% and g r a p h i t e witk krypton, t h e n stopping t h e inflow and observislg t h e r a t e a t which

2 -5 t h e krypton i s eliminated from t h e system. The f i r s t w i l l be a

The operation w i l l be done i n t h r e e phases.

s h o r t run (about 10 h r ) t o c a l i b r a t e t h e equipment.

Tize second run, of

about 2 days duration, w i l l y i e l d approximate values f o r t h e constants which are t o be measured.

The results of t h e s e two runs will be used

t o decide on t h e r a t e of krypton i n j e c t i o n and t h e d u r a t i o n of a t h i r d , long run.

The a n t i c i p a t e d r a t e of i n j e c t i o n i s

6 curiesiday o r l e s s

and t h e duration, chosen t o allow 85Kr concentrations t o reach steady s t a t e , i s expected t o be about 20 days. A t t h e end of t h e prescribed period, t h e i n p u t of 85Kr w i l l be

stopped and t h e decreasing "Kr

concentration i n t h e offgas w i l l be

followed c l o s e l y u n t i l t h e l e v e l becomes i n s i g n i f i c a n t .

The concentration

w i l l decrease r a p i d l y a t f i r s t as most of t h e krypton i n t h e salt i s

stripped, t h e n more slowly as krypton d i f f u s e s out of t h e g r a p h i t e i x t o t h e salt and thence i n t o t h e offgas stream. The t r a n s i e n t s i n t h e 85KZ concentration i n t h e offgas stream w i l l be analyzed t o y i e l d values f o r f u e l s a l t - g a s holdup, s t r i p p i n g rate

and t h e rate of t r a n s f e r from t h e g r a p h i t e t o t h e s a l t .

m e s e q.dar;%i-

t i e s can t h e n be used r a t h e r d i r e c t l y t o p r e d i c t values f o r xenon. These values will be incorporated i n t h e lss5Xe r e a c t i v i t y c a l c u l a t i o n f o r t h e nuclear s t a r t u p . Fuel-Drain-Tank System

2.3.2

The fuel-drain-tank s y s t e n c o n s i s t s of f u e l d r a i n tank No. 1 ( F D - l ) ,

f u e l d r a i n tank No. 2 (FD-2), f u e l f l u s h tank

(m),and

associated

piping. The two drain-tank afterheat-removal systems are a l s o included. P r e c r i t i c a l t e s t i n g will include t h e followigg items. 2.3.2.1

C a l i b r a t i o n of Steam Drums

The steam drums w i l l be c a l i b r a t e d by adding known increments of water from t h e previously c a l i b r a t e d feed-water tanks and by comparing t h e amount added with t h e i n d i c a t e d l e v e l .

The c a l i b r a t i o n curves t h u s

obtained w i l l be used t o s e t t h e operating parameters.

Details a r e given

i n Test Memo X I 2.3.2.2. 2.3.2.2

I c i t i a l Heatup -

During the i n i t i a l heatu? t h e system w i l l be purged and stress relieved, t h e thermal growt'a of t h e piping w i l l be checked, t h e heatv-p

2-6 4 a i d coolrlom rates w i l l t e d e t a n i n s d , and t h e necessary h e a t e r s e t t i n g s

f o r v a r i o ~ ~operating s conditions w i l l be obtained. Parge -The system.

system w i l l b e purged a t t h e same t i m e as t h e fuel

Details are given i n T e s t Memo XI 2.3.1.1-A.

Heater S e t t i n g s -The

hea:er-control

s e t t i n g s will b e determined

f o r holding t h e system a% various temperatxes.

During cooldown, t h e

e f f e c t of loss of e l e c t r i c a l . power w i l l be checked.

From tfiis information,

Mechanical l i m i t s w i l l be p u t

operating conditions can be established.

on h e a t e r c o n t r o l l e r s t o prevent overheating ddring filtire operation. Possible temperature e f f e c t s on t h e weigh-cell readings w i l l be noted. Details are given is Test Memo X I 2.3.2.2-B.

Thermal-Expansion E f f e c t s - P r i o r

t o heating t h e system, key

measilrements w i l l be taken on t h e piping and equipment. S t r e s s relievi.ng w i l l b e accomplished by holding t h e temperatures a t 13000F f D r a minimm of 100 t o u r s .

F k i l e h o t and af5er cooling down, t h e key measurements

w i l l be rechecked t o determine movement which could cause t r o u b l e i n t h e

future.

Details are given i n T e s t Memo X I 2.3.2.2-C.

2.3.2.3

I-ni ti a-l S a-l t-F-i ll

A small aqount of f l u s h s a l t will be added t o t h e system and w i l l be used t o fill t h e f r e e z e valves.

The rernainder of t h e f l u s h s a l t w i l l

then b e added t o f u e l d r a i n tar& No. 1. Weigh c e l l s will b e c a l i b r a t e d when t h e tanks are cold by adding knowE increments of weight. be r e c a l i b r a t e d as t h e s a l t i s added.

They w i l l

The weigh-cell readings when t h e Using t h e probe l o c a t i o n s as

l e v e l probes are actua5ed w i l l be notzd.

baselines, t h e eievatior-s of sdlt i n t h e tank w i l l be p l o t t e d vs weight of s a l t added and weigh-cell readings.

The f u e l d r a i n t a n k No. 2 and

t h e PLel f l u s h tank w i l l be c a l i b r a t e d by t r a n s f e r r i n g t h e s a l t i n increments and by observing t h e tank weights and l e v e l probes.

Frorr!

t h e s e curves, t h e weight and e l e v a t i o i of t h e salt i n t h e f u e l system cac be determined during f i l l o p e r a t i o m .

Details are given ii Test

Memo X I 2.3.2.3.

2.3.2.4

CoolCicna n Drain _ _ -Rates - - -(-S a-l t -i - - - Tank1 ---

ICorder t o deternine how

EOOL

s a l t w i l l f r e e z e i n a d r a i n tar&

if e l e c t r i c power i s l o s t , t h e power w i l l be t i r n e d o f f a l l k e a t e r s and

t h e s a l t w i l l be allowed t o cool approximately 200째F.

The curve w i l l be

2 -7

e f i r a p o l a t e d to de5ermine t h e f r e e z i n g tlme.

%tails are gives i n Test

Memo X I 2.3.2.4.

-----

Heat - - -Removal - - - -b x S t e m D m s

2.3.2.5

S u f f i c i e n t cooling capacity i s needed t o remove f i s s i o c - p r o d u c t a f t e r h e a t from t h e f u e l wben it i s drained t o t h e d r a i n tanks.

With

f l u s h s a l t i n a d r a i n tank, t h e steam drums will be p u t i n t o s e r v i c e arid t h e h e a t removal r a t e determined by t h e cooldown rate of t h e salt. !%e t e s t w i l l be terminated before t h e s a l t f r e e z e s .

D e t a i l s are given

i n T p s t Memo X I 2.3.2.5. Coolant System

2.3.3

The coolant system c o n s i s t s of t h e r a d i a t o r , coolant puznp, h e a t exchanger, and a s s o c i a t e d piping.

P r e c r i t i c a l t e s t i n g w i l l c o n s i s t of

t h e following items.

2.3.3.7-

_I n_i t_i a- l- Heatup --

During t h e i n i t i a l heatup t h e system w i l l be purged and stress relieved.

The thermal growth of t h e piping w i l l be checked, t h e heatup

and cooldown r a t e s , as well as temperature gradients, w i l l be determined, and t h e necessary h e a t e r s e t t i n g s f o r various operating conditfons w i l l be obtained.

Purge -Before

any s a l t - c o n t a i n i n g equipment i s heated or s a l t

added, t h e e n t i r e system w i l l be purged t o remove oxygen ar?d moisture. This w i l l be done by f i r s t evacuating and f i l l i n g t h e system with helium followed by an extended purge which w i l l continue through t h e heatup. Purging w i l l be conducted i n a sequence t o i n s u r e purging of a11 gas and

s a l t piping.

"he coolant pwnp w i l l be operated t o c i r c u l a t e helium

through t h e main loop.

Since t h e r e w i l l be no salt i n t h e f r e e z e valves,

t h e coolant d r a i n tanks w i l l be purged along with t h e coolant systen. Purging of t h e coolant o i l system i s a l s o included a t t h i s t i m e .

possible, t h e f u e l system, fuel-drain-tank system, cover-gas system, and offgas system w i l l be purged a t t h e same time.

Details a r e given

i n Test Memo XI 2.3.3.1-A.

Heater S e t t i n g s

-Dni%

t h e i n i - t i a l heatup a l l thermoco2plee w i l l

be monitored t o a s s u r e t h a t no cold s p o t s or excessive temperature gradiests exist.

Necessary adjustments of t h e h e a t e r c o n t r o l l e r s W i l l

be made s i n g , as a guide, previously prepared graphs of t h e ir,dica%ed

2 -8

h e a t e r cr;rreri< fs %e e s t i m 5 e d power p e r square f o o t of surface. -

Heater-

c o n t r o l s e t t i n g s w i l l b e de5emined f o r holdi-ng t h e system a t various temperatxres.

TJe rate of cooldown and temperature g r a d i e n t s during a

power outage will a l s o b e c3eeked.

From t h i s information mechanical

limits can be pGt or, t h e c o n t r o l l e r s , curves can be made t o show t h e i n t e r r e l a t i o n s h i p between h e a t e r c u r r e n t and equipment temperature, and t 5 n normal c o n t r o l set%ings can be e s t a b l i s h e d .

Details are given i n

Test Memo XI 2.3.3.1-B. Thermal Growth

- Stress

r e l i e f of i n d i v i d u a l components and piping

welds will be performed during assembly.

However, as p a r t of t h e i n i t i a l

heatup t h e e n t i r e system will b e h e l d a t 1300째F f o r 100 hours f o r addit i o n a l stress r e l i e f .

The tbermal growth of t h e piping system and t h e

operation of t h e constant-load p i p e supports w i l l be noted before, during and a f t e r t l e i n i t i d h e a t q .

The piping h e a t e r s i n s i d e t h e

r e a c t o r c e l l will be observed while a t operating t e a p e r a t u r e t o d e t e c t any apparent d i f f i c u l t i e s due t o t h e s h i f t i n g of t h e p i p i n g system. Details are given i n T e s t Memo X I 2.3.3.14.

2.3.3.2

I- n- i-t-i -a -l -F-i -l l- _ and - _Operation

During t h e i n i t i a l fill t h e l e v e l i n t h e system w i l l be c a l i b r a t e d The rate of f i l l w i l l be determined,

vs t h e an0un-t of salt added. _.

various coolant-pump tests w i l l be made, and t h e rate of cooling w i l l be checked under v a r i o s s conditions.

The e f f e c t of temperature on t h e

c o o l a z t - s a l t flow meter w i l l be investigated. i n i t i a l f i l l of t h e coolant system will

Level C a l i b r a t i o n -The

b e made by increasing t h e drain-tank pressure i n increments.

After

each p a r t i a l additior,, t h e l e v e l of t h e s a l t as i n d i c a t e d by t h e AP, t h e l o o p p i p e temperatures, and t h e weight of t h e salt i n t h e coolant d r a i n tark w i l l be deternine3.

From t5is information and t h e c a l i b r a t i o n

of t h e coolant d r a l n t a n k vs t k e e l e v a t i o n made previously, t h e weight i n t h e coolant system vs t h e e l e v a t i o n w i l l be p l o t t e d .

I n order t o

e s t a b l i s h f u t u r e operating paraxeters, t h e rate of f i l l w i l l be d e t e r mined a t various settings of t h e drain-tarik helium-supply valves and a t various s a l t elevations.

Tke salt l e v e l i n t h e pump bowl w i l l be

c a l i b r a t e d using t h e f l o a t i n d i c a t o r and both bu3blers. gi-Jen i n Test Memo X I 2.3.3.2-A.

Details are

S a l t Flowmeter -The

e f f e c t s of loop temperatures and temperatures

of t h e NaK-filled d i f f e r e n t i a l - p r e s s u r e c e l l s on t h e flow i n d i c a t e d by t h e c o o l a n t - s a l t flowmeter w i l l be determined f o r b a s e l i n e i n f o m a t i o n .

Details a r e given i n Test Memo XI 2.3.3.2-B. Cooling Rates -The

cooldown r a t e upon loss of e l e c t r i c power w i l l

be determined with salt c i r c u l a t i n g i n t h e system and without s a l t c i r c u The response t i m e needed t o s t o p t h e system cooldown and s t a r t

lation.

h e a t i n g w i l l be checked.

Tests w i l l a l s o be made t o determine t h e

temperature response w i t h and without c i r c u l a t i o n using only t h e emergency electric-power supply.

From t h i s information, t h e operating

p o l i c i e s during power outages can be f i n a l i z e d .

D e t a i l s a r e given i n

Test Memo X I 2.3.3.2-C. r a t e a t which t h e d r a i n valves

Freeze-Valve Thaw Rate -The

(FV 204 and 206) w i l l t h a w with and withofit e l e c t r i c power and t h e r a t e of d r a i n of t h e salt from t h e coolant system w i l l be determined under various operating conditions.

From t h i s information operating procedures

can be e s t a b l i s h e d which w i l l prevent f r e e z i n g of t h e salt i n t h e r a d i -

ator.

Inventory checks w l l l be made after each d r a i n t o determine t h e

h e e l l e f t i n t h e coolant system.

Details are given i n Test Memo

X I 2.3.3.2-D.

2.3.3.3

Radiator - - - -and - -Heat-Removal - - - _ -- %stem --

The r a d i a t o r doors, blowers, and dampers w i l l be checked t o a s s u r e t h a t they operate as designed and t h a t t h e c o n t r o l c i r c u i t s function properly.

The stack flowmeter will be calibrated.

Radiator Door Tests -The tested.

operation of t h e r a d i a t o r doors w i l l be

Most of t h e s e t e s t s w i l l be made with t h e coolant system a t

ambient temperature.

They include:

rate of r a i s e , rate of lowering

under power and during a l o a d scram, and p o s i t i o n change with blowers on.

The operation of t h e doors w i l l also be checked while a t 1200째F.

Warpage will be determined a f t e r t h e heating and cooling cycles. Details a r e given i n T e s t Memo X I 2.3.3.3-A. Radiator Cooling - T e s t s

w i l l be made t o determine t h e cooling

r a t e which would occur i f 50th r a d i a t o r doors were d r q p e d with s a l t i n t h e system,

D e t a i l s of t h i s a r e given i n Test Memo X I 2.3.3.3-B.

2-10 J

Damper P o s f t i o r

- m,he

mEasured damper p o s i t i o n vs i n d i c a t e d

p o s i t i o n w i l l be meassxed and t h e r e p r o d w i b i l i t y checked before heatup. Several p o i n t s will be rechecked after heatxp and cooldowc.

of movern?rt of t h e -3mpers will be determined.

The rate

The operation of t h e

dampers w i l l be checkec? w ? i i e t h e system i s a t 12CO"F.

Details are

given i n T e s t Memo XI 2.3.3.3-C. Stack Flow Rates -The

s t a c k air-flow instrument w i l l be c a l i b r a t e d

over tl-Le rarge of 20,000 t o 200,000 scfm by measuring v e l o c i t y p r o f i l e s . Flow rates a t varioLcscombinations of blowers, door p o s i t i o n s , and damper p o s i t i o n s w i l l be determined f o r f u t u r e reference.

Details are

given i n Test Memo XI 2.3.3.3-D. Radiator Air Leakage - V e n t i l a t i o n

i s provided t o maintain t7ne

coolant c e l l a t a lower press2re t h a n t h e high-bay area.

Tests w i l l be

made a t v a - ~ L o ~door s and damper p o s i t i o n s with both r a d i a t o r blowers i n operatior, t o a s s u r e t h a t leakage does not p r e s s u r i z e t h e c e l l .

Details

are given i n T e s t Memo XI 2.3.3.3-E.

2.3.4

Coolact Drain-Tank System The coolant draic-tank system c o n s i s t s of t h e coolant d r a i n tank P r e c r i t i c a l t e s t i n g w i l l c o n s i s t of t h ? following

and a s s o c i a t e d piping.

items.

2.3.4.1

I ni ti al Heatip ---

During t h e i c i t i a l heatup t h e system w i l l b e purged and stress relieved, She therma2. g r o w t h of t h e piping will be checked, t h e heatup and cooldown rates w i l l be determice3, and t h e necessary h e a t e r s e t t i r , g s f o r vario.;s

operating conditions w i l l be obtained.

Purge -The systzm.

system w i l l be purged a t t h e same t i m e as t h e coolant

Details are gi-,ren i n "est Memo X I 2.3.3.1-A.

Heats? Set-tvings -The

h e a t e r c o n t r o l s e t t i n g s w i l l be determined

t o r holding the system a t various temperatares.

Attenpts w i l l be made

t o hold a l l tenperatures w i t k i i c k 100 F of each other. t h e e f f e c t of l o s s of e l e c t r i c power w i l l be checked. i-f AL

o ~ i t i o : : operat::q

c m d i t i o n s caT? be e s t a b l i s h e d .

During cooldown,

From t h i s MecLanical l i m i t s

w i l l be p-t

on heat?? coxbroliers t o prevent overheating during f u t d r e

opera",!.on.

PossiSle tm?era",;-.re e f f e c t s o n t h e weigh-cell readings

w i l l be noted.

Details art: given i n T e s t Memo X I 2.3.4.2-B.

2 -11

Tnemal Growth -Prior

t o heating t k e system, key measurements

w i l l be taken on t h e piping and equipment.

S t r e s s r e l i e v i n g w i l l be

accom2lished by holding t h e temperatures a t 1300째F f o r a minimum of 100 hours.

While h o t and a f t e r cooling down, t h e key measurements w i l l

be rechecked t o determine movement which could cause t r o u b l e i n t h e future. 2.3.4.2

D e t a i l s are given i n T e s t Memo X I 2.3.4.2-C. I n i t i a l S a l t F i l l and C a l i b r a t i o n

- - - - - - - - c - - - - - - - -

A small amount of coolant s a l t w i l l be added t o t h e system and w i l l be used t o f i l l t h e f r e e z e valves. be added t o coolant d r a i n tank.

The remainder of t h e s a l t w i l l t h e n

The weigh c e l l s w i l l be c a l i b r a t e d when

t h e tank i s cold by adding known increments of weight. recalibrated vs t h e weight of s a l t added.

They will be

The weigh c e l l - r e a d i n g s when

t h e l e v e l probes a r e actuated w i l l be noted.

Using t h e probe l o c a t i o n s

as baselines, t h e e l e v a t i o n s of s a l t i n t h e tank w i l l be p l o t t e d vs weight of s a l t added and weigh-cell readings.

From t h e s e curves, t h e

weight and e l e v a t i o n of t h e salt i n t h e coolant system can be determined during fill operations.

2.3.4.3

Details a r e giTien i n T e s t Memo X I 2.3.4.3.

Cooldown - - - -Rates - - -(-S a-l t-i-n -Drain - - -Tank1 -

I n order t o determine how soon s a l t w i l l f r e e z e i n t h e d r a i n tank i f e l e c t r i c power i s l o s t , t h e power w i l l be turned off a l l h e a t e r s and 0

t h e s a l t w i l l be allowed t o cool approximately 200 F. be e x t r a p o l a t e d t o determine t h e f r e e z i n g time.

The curve w i l l

Details are given i n

T e s t Memo XI 2.3.4.4.

2.3.5

Cover-Gas and Offgas Systems The cowr-gas system provides a helium supply t o purge t h e salt

systems, t o t r a n s f e r s a l t by p r e s s u r i z a t i o n , and to provide an i n e r t atmosphere.

The offgas system provides holdup f o r t h e f i s s i o n gasses

from t h e f u e i system and fuel-drain-tank system.

It a l s o includes vent

l i n e s from t h e coolant system, coolant-drain-tank system, and l u b e - o i l system t o t h e s t a c k .

2.3.5.1

Purging _ _ - - - -t h e @stem --

Before purging t h e f u e l and coolant systems, t h e cover-gas system

w i l l be purged of air by evacuating and then pressuriziqg wit5 c y l i n d e r helium.

The purge w i l l be c o n t i m e d with c y l i n d e r helium during the

i n i t i a l purge of f u e l and coolant systems and t h e n with t r e a t e d helium

2-12 J

during t h e f i n a l purge of t h e f u e l and coolant systems. i s purged when the systems which it vents are purged.

The offgas system

The d e t a i l e d

procedure f o r evacuating and p r e s s u r i z i n g t h e cover-gas system i s given i n Test Memo X I 2.3.5.1.

CharcoalIlBed-Retenqi~n-T~mg

2.3.5.2

The helium purge from t h e f u e l pump flows through t h e main charcoal beds which are desigr,ed t o hold up t h e a s s o c i a t e d fission-product gases long enough t o allow them t o decay s u f f i c i e n t l y s o t h a t they can be d i s charged s a f e l y from t h e s t a c k t o t h e atmosphere.

The r e q u i r e d holdup f o r

K r a t 10 Mw operation i s 7 1/2 days a t design c a r r i e r - g a s flow r a t e s .

To determine t h a t t h e beds meet t h e design requirements, a b u r s t of "Kr

w i l l be charged i n t o t h e bed i n l e t and t h e discharge stream w i l l be

monitored f o r a c t i v i t y t o determine t h e holdup time i n t h e bed. helium c a r r i e r - g a s flow r a t e s w i l l be used during t h e t e s t .

Various

Details a r e

given i n Test Memo Xi 2.3.5.2. 2.3.5.3

~har~ogl~Bgd-Pr_egs~rg

The pressure drop across t h e main charcoal beds w i l l be measured over t h e expected flow range using i n s t a l l e d instrumentation.

This w i l l

check t h e design c a l c u l a t i o n s and a s s i s t i n determining t h e bed condition during r e a c t o r operations.

& t a i l s of t h e t e s t a r e given i n Test Memo

X I 2.3.5.3.

2.3.5.4

~x~ggn~R~m~v~r_arzd-~y~r-P~r~o~m~n~e

Exact prototype u n i t s o f both t h e oxygen-remover and dryer were used i n t h e development program for t h e cover-gas system.

The performance

of t h e i n s t a l l e d u n i t s w i l l be determined by analyzing t h e i n l e t and outl e t helium for oxygen and moisture during system purging and p r e c r i t i c a l testing.

No loading t e s t s a r e planned a t t h e r e a c t o r s i t e f o r e i t h e r the

oxygen-removal u n i t or t h e dryer. 2.3.6

O i l Systems

The two o i l systems a r e a u x i l i a r i e s of t h e f u e l and coolant s a l t pumps.

They provide both l u b r i c a t i n g o i l , f o r bearings and s e a l s , and

cooling o i l f o r t h e pump r a d i a t i o n s h i e l d s .

The t e s t program w i l l c o n s i s t

of various t e s t s and c a l i b r a t i o n s necessary f o r proper operation.

Both

systems w i l l be given a general shakedown before s t a r t u p of t h e s a l t pumps.

2-13 2.3.6.1

FiGa& &egk-Tgsf,

The o i l systems a r e p a r t s of t h e secondary containment and w i l l be helium l e a k t e s t e d i n conjunction with t h e f u e l and coolant systems.

For

d e t a i l s see Test Memo X I 2.3.1.3. 2.3.6.2

ca&ibrgtion gf-SugElx End

Oil, cat&

Enkg

During normal operation t h e r e w i l l be a small amount of o i l leakage through t h e s a l t pump seal. catch tank.

This i s c o l l e c t e d and measured i n t h e o i l

A s e r i o u s o i l l e a k here o r elsewhere i n t h e system w i l l show

up as a decrease i n o i l l e v e l i n t h e supply tank.

Therefore both the

supply-tank and catch-tank l e v e l i n d i c a t o r s w i l l be c a l i b r a t e d p r i o r t o operation. 2.3.6.3

& t a i l s a r e given i n Test Memo X I 2.3.6.2

sgrgepcy g u ~ L y

It i s important t h a t t h e systems supplying o i l t o t h e s a l t pumps be r e l i a b l e .

Details a r e given i n t h e operating procedures f o r s t a r t u p

of standby pumps under various operating conditions, operating with one o i l pump supplying both s a l t pumps, and adding o i l during operation without v i o l a t i n g containment.

The adequacy of the design w i l l be t e s t e d by

simulating abnormal conditions and by operating t h e systems as d e t a i l e d i n Section 9H, Part V I I I , Operating Procedures. 2.3.6.4

IjeatIEzcgaEggr-Tgs3

The cooling systems on t h e o i l supply tanks are designed with suff i c i e n t capacity f o r t h e operation of both s a l t pumps a t f u l l r e a c t o r power w i t h one o i l system.

Fouling of t h e surfaces could reduce t h e h e a t

t r a n s f e r c a p a b i l i t y below t h e design value.

Therefore, p e r i o d i c checks

w i l l be made t o d e t e c t changes i n t h e o v e r a l l h e a t t r a n s f e r c o e f f i c i e n t .

S h o r t l y a f t e r s t a r t u p of t h e system, tests w i l l be made a t s e v e r a l water and o i l flows and heat-removal r a t e s t o o b t a i n base information.

Details

a r e given i n Test Memo X I 2.3.6.4. 2.3.7

Chemical Processing System The chemical processing system c o n s i s t s of t h e f u e l storage tank,

t r a n s f e r l i n e s f o r moving s a l t from t h e drain-tank system and a gas sparging system f o r removal of oxygen or uranium from t h e s a l t . Equipment Preparation v

- The

e n t i r e chemical processing system w i l l

be helium l e a k checked during construction and component f a b r i c a t i o n .

2- 14 A f t e r l e a k t e s t i n g , t h e s a l t - h a n d l i n g p a r t of t h e system w i l l be purged with n i t r o g e n gas, t o remove a l l moisture and oxygen.

When t h e moisture

and O2 have been removed, t h e system w i l l be heated t o 1200'F and p r e s s u r e tested. Tank C a l i b r a t i o n s - P r i o r t o operation, t h e c a u s t i c n e u t r a l i z e r and c a u s t i c - a d d i t i o n tanks w i l l be c a l i b r a t e d using water.

The fuel-storage-

tank weighing system and u l t r a s o n i c probe w i l l be c a l i b r a t e d during t h e i n i t i a l s a l t a d d i t i o n from t h e f u e l f l u s h tank by comparing t h e weight of s a l t i n t h e two tanks. O9 Removal C a l i b r a t i o n

- Two

methods of determining t h e amount of

oxygen removed from t h e s a l t as water vapor during H2-HF processing cons i s t of an e l e c t r o l y t i c hygrometer t o measure moisture i n t h e offgas and a syphon p o t t o measure increments of condensed water vapor.

These w i l l

be c a l i b r a t e d and compared dluring a t e s t using a mixture of water vapor and nitrogen. Flush-Salt Treatment-

The f i n a l system t e s t w i l l c o n s i s t of r e -

moving t h e oxygen from t h e f l u s h s a l t which i s used during t h e p r e c r i t i c a l operation of t h e f u e i system.

This t e s t w i l l determine t h e system

e f f i c i e n c y and i n d i c a t e any modifications which a r e needed before t h e system i s contaminated by processing f u e l s a l t . 2.3.8

Leak-Detector System This system c o n s i s t s of e i g h t headers, each of which i s connected

t o a common helium supply on one end and by means of s t a i n l e s s s t e e l tubing t o t h e r i n g grooves of i n - c e l l f l a n g e s on t h e o t h e r end.

Normally

t h e l e a k - d e t e c t o r system w i l l be a t a higher p r e s s u r e than t h e systems being monitored.

The system will d e t e c t f l a n g e leaks, by a drop i n system

pressure, and prevent outleakage by maintaining a b u f f e r of helium.

Pre-

c r i t i c a l t e s t i n g w i l l c o n s i s t of t h e following items. 2.3.8.1

ca&i&rgt&og

I n order t o convert t h e pressure changes t o volumetric l e a k r a t e s , i t i s necessary t o k n o w t h e volume of various segments of t h e system.

Each header, l e a k - d e t e c t o r l i n e , e t c ., w i l l be c a l i b r a t e d by equalizing p r e s s u r e with a bomb of known v o l m e . be c a l c u l a t e d from changes i n p r e s s u r e . Test Memo X i 2.3.8.1.

The volumes of t h e system w i l l For c a l i b r a t i o n d e t a i l s , s e e

2-15 2.3.8.2

BXgLng

Before p u t t i n g t h e l e a k d e t e c t o r system i n t o operation, t h e headers and l i n e s w i l l be purged of oxygen.

The headers w i l l be purged by

p r e s s u r i z i n g t o 100 p s i g with helium and venting t h r e e times,

The l i n e s

w i l l be purged by bleeding gas through t h e l e a k d e t e c t o r l i n e s t o t h e

f l a n g e s before t h e flanges a r e sealed. 2.3.9

Cooling Water Systems Potable water i s supplied t o t h e MSRE from t h e X-10 a r e a .

After

passing through a backflow preventer, it i s c a l l e d process water and i s used as makeup for the cooling tower and f o r o t h e r o u t - o f - c e l l cooling and process uses.

Cooling-tower water which i s c i r c u l a t e d c e n t r i f u g a l pumps

provides cooling f o r t h e treated-water cooler and o t h e r o u t - o f - c e l l equipmeit.

All i n - c e l l cooling i s done by t r e a t e d water which i s c i r c u -

l a t e d by c e n t r i m g a l pumps.

P r e c r i t i c a l t e s t i n g w i l l c o n s i s t of t h e

following items. 2.3.9.1

zo&a&lg-waqer gygtsm

More than adequate supply I s a v a i l a b l e t o t h e a r e a ; however, t h i s

w i l l be v e r i f i e d during r e a c t o r s t a r t u p . 2.3.9.2

Pr_ocegsIWztgr-Sys&erq

The backflow preventers w i l l be t e s t e d i n accordance with ORNL Standard P r a c t i c e Procedure No. 14.

For d e t a i l s see Section 4C, Part V I I I ,

Operating Procedures.

2.3.9.3

C o ~ l ~ n g - Sygtgm ~ o ~ e ~

The cooling-tower system w i l l be f i l l e d and operated t o a s s u r e t h e adequacy and r e l i a b i l i t y of t h e components.

& t a i l s are given i n Test

Memo XI 2.3.9.3. 2.3.9.4

.psateA-waLer

gygtgm

The treated-water system w i l l be f i l l e d with condensate and a l l equipment operated when t h e h e a t t r a n s f e r c o e f f i c i e n t of the t r e a t e d water cooler i s measured.

Also, t h e condensate makeup r a t e w i l l be

measured and c a l i b r a t i o n s of t h e system and tank volumes w i l l be made. Condensate Makeup

- The

condensate makeup rate w i l l be determined

by measuring t h e t i m e t o produce a measured amount of condensate from t h e Y

normal steam supply.

Condensaxe w i l l be used t o c a l i b r a t e t h e various

2- 1 6 J

tanks by adding or removing measured amounts of condensate.

These

c a l i b r a t i o n s w i l l be used t o determine the r a t e of water usage.

&tails

of these t e s t s a r e given i n T e s t Memo X I 2.3.9.4-A. Volume Calibration

- The

system volume c a l i b r a t i o n w i l l be made by

comparing t h e water a n a l y s i s before and a f t e r a d d i t i o n of known amounts of a corrosion i n h i b i t o r .

The c a l i b r a t i o n s w i l l be used i n c a l c u l a t i n g

chemical a d d i t i o n s required t o maintain t h e proper water treatment. Details a r e given i n T e s t Memo X I 2.3.9.4-B.

Treated-Water Cooler - The heat t r a n s f e r c o e f f i c i e n t of the t r e a t e d

water cooler w i l l be determined t o provide a b a s e l i n e f i g u r e which can be used i f tube fouling i s suspected.

Details a r e given i n Test Memo

X I 2.3.9.4-C.

E f f e c t of Water Flow on Cell Temperature and Pressure

- The

effect

of closing the r a d i a t i o n block valves on c e l l temperature and pressure w i l l be t e s t e d .

A f t e r the c e l l s a r e closed and sealed, t h e water t o the

space coolers w i l l be shut off and the r a t e of pressure and temperature increase will be measured. When t h e surge-tank vent valve c l o s e s on a c t i v i t y i n t h e t r e a t e d water, the system becomes an unvented system.

The e f f e c t on water makeup

and c i r c u l a t i o n w i l l be t e s t e d w i t h the vent closed.

Details of t e s t i n g

the block valve e f f e c t s are given i n Test Memo X I 2.3.9.4-D. Thermal Shield s h i e l d i s q u i t e low.

- The

permissible pressure i n t h e r e a c t o r thermal

During the i n i t i a l s t a r t u p of the treated-water

system, t e s t s w i l l be conducted t o insure t h a t the thermal s h i e l d i s adequately protected a g a i n s t excessive pressures. 2.3.10

Component-Cooling Systems

The primary component-cooling-air system c o n s i s t s of a c i r c u l a t i n g system i n which gas from t h e r e a c t o r and drain-tank c e l l s i s compressed, cooled, and reused t o cool i n - c e l l components ( f r e e z e valves, pump bowl, c o n t r o l rods, r e a c t o r neck, and graphite-sampler neck).

A secondary

cooling-air system supplies a i r f o r cooling the f r e e z e valves l o c a t e d outside t h e r e a c t o r and drain-tank c e l l s .

s i s t of the following items.

P r e c r i t i c a l t e s t i n g w i l l con-

2- 17 2 3 10.1 gak-Tes&iGg e

The s e c t i o n of t h e primary component-cooling system which i s o u t s i d e t h e main c e l l s i s p a r t of t h e r e a c t o r containment enclosure.

A l l flanged

j o i n t s i n t h i s s e c t i o n w i l l be soap checked f o r l e a k s and w i l l be rechecked during t h e containment l e a k t e s t .

Each component w i l l be hydro-

s t a t i c a l l y t e s t e d during manufacture, and t h e e n t i r e system w i l l be pneumatically t e s t e d a f t e r i n s t a l l a t i o n .

Details are given i n Test Memo

XI 2.3.10.1.

2.3.10.2

gegt-TyaI2;sfey Cogfficignz gf-HgaL Exchsngey

A h e a t balance w i l l be made on t h e heat exchanger, and t h e h e a t

t r a n s f e r c o e f f i c i e n t w i l l be c a l c u l a t e d .

This w i l l be used as a b a s i s

f o r subsequent evaluation of the heat-exchanger performance

D e t a i l s are

given i n Test Memo X I 2.3.10.2. 2.3.10.3

egl=Pgng Cogling-&

Flgw-Cgl&b;aiign

The e f f e c t of the c o o l i n g - a i r flow r a t e t o t h e fuel-pump bowl on t h e temperature d i s t r i b u t i o n w i l l be determined.

This w i l l allow s e l e c -

t i o n of t h e optimum flow t o minimize thermal s t r e s s e s on t h e pump bowl. Details are given i n Test Memo X I 2.3.10.3.

2.3.10.4

Flow_A_djgsimgni

The flow t o t h e freeze valves and o t h e r equipment served by both t h e primary and secondary component-cooling-air systems w i l l be set t o give t h e d e s i r e d f r e e z e valve operating c h a r a c t e r i s t i c and equipment cooling. D e t a i l s are given i n Section 41, Part VIII, Operating Procedures. 2.3.10.5

Flow_Stab-iLi&y

The s t a b i l i t y of a i r flows w i l l be checked by observing t h e system pressure and monitored thermocouples on t h e equipment during periods when a i r flow i s being changed, such as during operation of f r e e z e valves, or

t h e evacuation of t h e c e l l . 2.3.11

Details a r e given i n T e s t Memo X I 2.3.10.5.

Instrument-Air and Auxiliary-Air Systems

Clean, dry, compressed a i r i s supplied t o t h e MSRE instruments by

a r e c i p r o c a t i n g compressor and h e a t l e s s a i r dryer with a spare compressor and dryer i n a standby.

Cylinders of nitrogen provide emergency gas pres-

s u r e t o t h e more important instruments.

Auxiliary compressed a i r i s

2- 18 supplied by a t h i r d r e c i p r o c a t i n g a i r compressor f o r t h e operation of pneumatic t o o l s and o t h e r p l a n t uses.

P r e c r i t i c a l t e s t i n g w i l l c o n s i s t of

t h e following items. 2.3.11.1

GagasiLy-of:

Liz Corgxegsgrg

I n order t o e s t a b l i s h a base f o r comparing t h e f u t u r e performance of t h e compressors, t h e capacity of each instrument-air compressor w i l l be checked while new.

Flow rates as i n d i c a t e d by t h e i n s t a l l e d instruments

w i l l be recorded w i t h t h e system operating a t s t e a d y - s t a t e design con-

ditions.

The r e l a t i v e loading and unloading times w i l l a l s o be determined

a t various flow r a t e s .

2.3.11 2

Details are given i n T e s t Memo X I 2.3.11.1.

pxex Peyfg;agce

To ensure proper operation of t h e pneumatic instruments, t h e dryers must reduce t h e moisture content of t h e a i r t o a dewpoint of -20째F.

The

moisture content of the discharge a i r from each dryer w i l l be monitored with i n s t a l l e d instruments.

A t design operating conditions t h e automatic

timing cycle of each dryer w i l l a l s o be checked.

Details a r e given i n

Test Memo X I 2.3.11.2. 2.3.11.3

gmgrgency g u p ~ i y

S u f f i c i e n t emergency instrument-air capacity should be a v a i l a b l e t o a s s u r e an o r d e r l y shutdown of the r e a c t o r i n case of loss of both i n s t r u ment-air compressors.

Both compressors w i l l be stopped and t h e rate of

pressure drop w i l l be determined.

T i m e s w i l l be noted when various

annunciations or instrument f a i l u r e s occur.

Comparison of t h e s e with

the t i m e necessary t o d r a i n the system should i n d i c a t e whether t h e

emergency supply i s adequate.

Detailed procedures a r e given i n T e s t Memo

X I 2.3.11.3.

2.3.12

Instrmentation

A l l instruments w i l l be thoroughly checked p r i o r t o operation t o

ensure t h a t they function properly. 2.3.12.1

Ir~~t-~ent-Cal~bxation

All instruments w i l l be c a l i b r a t e d following f a b r i c a t i o n .

Each w i l l

be checked t o e n s - n e t h a t t h e transmitted s i g n a l covers t h e proper range. The system recorders and i n d i c a t o r s w i l l be checked with a p r e c i s i o n i n s t r u ment t o m s u r e t h e proper value i s read out.

2- 19 2.3.12.2

Teggratye

Each thermocouple w i l l be checked f o r c o n t i n u i t y and r e s i s t a n c e . Temperature readout instruments w i l l be c a l i b r a t e d by feeding i n m i l l i v o l t s i g n a l s which correspond t o the temperature range t o be covered. 2.3.12.3

Control C i g c u i t s

All c o n t r o l c i r c u i t s and c o i t r o l loops w i l l be checked following i n s t a l l a t i o n f o r c o n t i n u i t y and proper c o n t r o l a c t i o n .

These a r e covered

by t h e instrument s t a r t u p check l i s t , Section 4H, Part V I I I , Operating Procedures. 2.3.12.4

Coguter

The computer t o be used f o r scanning, recording, and processing r e a c t o r d a t a w i l l be checked out and t e s t e d independently of t h e r e a c t o r system.

However, a complete checkout of t h e computer w i l l require, not

only operation of t h e r e a c t o r system, but t h e production of nuclear power. Therefore, it may be expected t h a t some c o r r e c t i o n s and modifications of t h e computer system and/or programs w i l l be required a f t e r t h e system

i s nominally i n s e r v i c e . The pre-operational t e s t i n g of t h e computer w i l l be performed i n

two s t a g e s .

The f i r s t s t a g e w i l l take place a t t h e vendor's p l a n t p r i o r

t o shipping and t h e second w i l l take place a t t h e r e a c t o r s i t e a f t e r i n s t a l l a t i o n of t h e equipment.

Both s t a g e s w i l l be a j o i n t e f f o r t by

members of t h e O W L s t a f f and r e p r e s e n t a t i v e s of t h e computer manufacturer. A f t e r completion of t h e second s t a g e of t e s t i n g , t h e computer system w i l l be placed i n normal operation and made a v a i l a b l e t o the r e a c t o r

operating s t a f f .

S u b s t a n t i a l on-line operating experience w i l l be

accumulated so t h a t complete r e l i a n c e can be placed on a l l a s p e c t s of t h e computer operation. The f i r s t phase of t h e checkout w i l l begin with t h e normal checks, by t h e manufacturer, of q u a l i t y , workmanship, and o p e r a b i l i t y of t h e computer i t s e l f and a l l t h e a s s o c i a t e d subsystems and p e r i p h e r a l devices. This w i l l be followed by assembly and checkout of a l l programs t o be used

i n t h e computer.

Operation of t h e system w i l l then be t e s t e d with f i x e d

values for a l l i n p u t parameters; values t h a t are expected t o be t y p i c a l f o r both full-power and low-power operation of t h e r e a c t o r w i l l be used.

2-20 I n cases where a computational program may follow any of s e v e r a l paths depending on t h e input value, a v a r i e t y of values will be used t o allow a l l p o s s i b i l i t i e s t o be checked.

This phase w i l l be concluded with a

series o f customer-acceptance tests t o demonstrate t h a t t h e computer meets a l l requirements.

The second phase o f t h e checkout w i l l be conducted a f t e r t h e computer system has been i n s t a l l e d a t t h e r e a c t o r s i t e and a l l of t h e r e a c t o r system s i g n a l s have been connected t o i t .

This w i l l permit complete

t e s t i n g of a l l a s p e c t s of t h e computer operation except those a s s o c i a t e d with nuclear-power operation of t h e r e a c t o r . The d e t a i l s of the procedures used i n checking t h e computer are t h e j o i n t r e s p o n s i b i l i t y of ORNL and t h e computer manufacturer.

Since t h e

i n i t i a l checkout i s not d i r e c t l y a s s o c i a t e d with t h e r e a c t o r system and does not involve operating personnel, it w i l l be described s e p a r a t e l y . The periodic checks t o be performed by operating personnel w i l l be published a s p a r t of t h e operating procedure f o r t h e computer. 2.3.13

E l e c t r i c a l System

3% Feedgr-SwitchoXey

2.3.13.1

The 7503 Area i s supplied by two 13.8-kv feeders, a p r e f e r r e d l i n e

(ORNL C i r c u i t 234) and

8 1 1

a l t e r n a t e (OmL C i r c u i t 294).

Low voltage on

C i r c u i t 234 w i l l i n i t i a t e an automatic t r a n s f e r t o C i r c u i t 294 a f t e r a

I- t o 10-sec delay, providing t h e r e i s voltage on C i r c u i t 294 and no f a u l t between t h e two motor-operated switches.

$-, P a r t

T e s t Memo

XZ 2.3.13.1 and i n

2.3.l3,2

2 g r g t i o c ~f-D&ege&s-3~ -aEd_5

Details a r e given i n

VTII, Operating Procedures.

Diesel Generators 3 and 4 supply 480-v AC c u r r e n t a f t e r t h e l o s s of both TVA feeders f o r operating motorized process equipment, some l i g h t i n g , and some instrument power.

Generator

operating process e l e c t r i c h e a t e r s .

5 supplies 480-v

AC power f o r

Tests w i l l be run t o determine the

preoperational s e t t i n g s t o b r i n g t h e u n i t s t o power s a f e l y from t h e remote start.

The a c t u a l operating load of each d i e s e l w i l l be compared t o t h e

t a b u l a t e d load.

P a r a l l e l operation of Generators 3 and 4 with TVA w i l l

a l s o be t e s t e d .

Details a r e given i n Test Memo X I 2.3.13.2

2- 21 2.3.13.3

&85@

systg

The 48-v system i s used t o supply uninterrupted power f o r c r i t i c a l instrumentation.

This power i s normally supplied from e i t h e r of two

3-kw, A C - E M. G. s e t s with a b a t t e r y " f l o a t i n g " on-line t o f u r n i s h emergency power a f t e r a l o s s of t h e normal e l e c t r i c a l supply.

A test w i l l

be made t o determine t h e a c t u a l time during which t h e b a t t e r i e s will supply adequate power t o t h e instruments.

Details a r e given i n T e s t Memo

X I 2.3.13.3.

The two M. G. s e t s must be operated i n p a r a l l e l t o charge

the battery.

This procedure (Section

9,P a r t

V I I I , Operating Procedures)

w i l l be t e s t e d .

2.3.13.4

250-1 &JSJ&

The 250-v E system supplies power f o r E emergency l i g h t s , breaker t r i p power, feeder t r a n s f e r power, and a 2 5 - k ~E - A C M. G . s e t .

This

system i s normally supplied from a l 2 5 - k ~A C - E M. G. s e t , and has a b a t t e r y capable of supplying emergency power f o r two hours under fill Low voltage from t h e 2 5 - k ~M. G. set w i l l throw an automatic

load.

switch, t r a n s f e r r i n g t h e power f o r Instrument Panels 2 and 3 t o Generator 4. The e f f e c t i v e l i f e of t h e b a t t e r y w i l l be t e s t e d under various loads, and t h e automatic t r a n s f e r of t h e instrument power w i i l be t e s t e d as o u t l i n e d i n Test Memo X I 2.3.13.4, 2.3.13.5

Ernsrgegcy & i g h g

Emergency E l i g h t s come on automatically on l o s s of AC power t o Lighting Panel H.

The E l i g h t s w i l l be tested by opening t h e Lighting

Supply 13reaker and a check w i l l be made t o a s s u r e t h a t a l l a r e a s are adequate1y 1ight ed 2.3.14 2.3.14.1

S h i e l d and Containment

znLtza& Cell-Tgstillg

The construction of t h e r e a c t o r c e l l and drain-tank c e l l are p a r t of

a major building-modification c o n t r a c t .

Upon completion of t h e s e c e l l s ,

and p r i o r t o acceptance by ORNL, t h e c e l l s w i l l be s e a l e d and hydros t a t i c a l l y t e s t e d t o 48 p s i g and then pneumatically l e a k t e s t e d a t 20 p s i g and -5 p s i g . 2.3.14.2

Details of t h e t e s t are o u t l i n e d i n T e s t Memo X I 2.3.14.1.

@gGer-Lea& Test

The r e a c t o r c e l l , drain-tank c e l l , and c e r t a i n appendages comprise t h e secondary containment of t h e r e a c t o r system.

A l l piping e n t e r i n g o r

2- 22 leavirLg the c o n t a i m e n t i s protected a g a i n s t out-leakage of a c t i v i t y during an accident by check valves o r automatic block valves.

These

containment check valves and block valves w i l l be l e a k t e s t e d p r i o r t o operation.

The secondary containment of t h e r e a c t o r w i l l be l e a k t e s t e d

a t 20 psig, 10 psig, 5 psig, 2 p s i g and -2 p s i g .

The data w i l l be

extrapolated t o the expected leakage f o r t h e maximum c r e d i b l e accident and must not exceed 1% of the c e l l volume i n 24 hours a t 39 psig.

Details of

the l e a k t e s t are covered by S h i e l d and Containment Check L i s t s , (Section 4E, P a r t V I I I , Operating Procedures). 2.3.14.3 ~ a ~ o r - C o n d ~ n ~ i g g - S y s 4 e q ! The vapor-condensing system i s i s o l a t e d from t h e r e a c t o r c e l l by two

rupture d i s c s .

This system i s designed t o l i m i t t h e secondary-containment

pressure t o 39 p s i g during the maximum c r e d i b l e accident.

This system

w i l l be l e a k t e s t e d a t t h e same time as the r e a c t o r and drain-tank c e l l s

and t o the same s p e c i f i c a t i o x , . 2.3.14.4

CoggngaJigg-Vglpg

The compensated volume c o n s i s t s of s e v e r a l s e a l e d pipe volumes i n the r e a c t o r and drain-tank c e l l s i n t o which the c e l l pressure can be admitted.

The compensating volume can then be i s o l a t e d from t h e c e l l s and

c e l l l e a k r a t e determined by measuring the d i f f e r e n t i a l pressure between the c e l l s and t h i s volume using a s e n s i t i v e gage.

Since t h i s l e a k - t i g h t

volume i s i n s i d e the c e l l s and a t thermal equilibrium, t h e l e a k rate measured should be independent of changes i n c e l l temperature. s a t i n g volume w i l l be l e a k t e s t e d during f a b r i c a t i o n .

The compen-

The e f f e c t i v e n e s s

of t h e temperature compensation w i l l be determined during the prepower leak testing. 2.3.14.5

*tails

of t h e t e s t a r e given i n T e s t Memo X I 2.3.14.4.

sa&i&rgtion G f - S g u E

Sumps a r e provided i n the r e a c t o r c e l l and drain-tank c e l l t o c o l l e c t the leakage from any i n - c e l l water-containing equipment. a r e measured by bubbler-type l e v e l i n d i c a t o r s .

Both sump l e v e l s

The sumps w i l l be c a l i -

b r a t e d f o r volume and l i q u i d depth versus instrument reading. given i n Test Memo X I 2.3.14.5.

&tails are

2-23 2.3.15

V e n t i l a t i o n System

The v e n t i l a t i o n system i s designed t o v e n t i l a t e a l l areas where the

p o t e n t i a l hazard from r a d i o a c t i v e contamination i s high. p r e s s u r e s are maintained i n these areas by t h e s t a c k fan.

Subatmospheric The a i r

exhausted from t h e s e a r e a s passes through an absolute f i l t e r before it i s discharged t o the containment v e n t i l a t i o n s t a c k .

The following tests

of t h i s system w i l l be performed. 2.3.15.1

Filtgr-Tgst

A DOP smoke t e s t w i l l be performed on t h e a b s o l u t e f i l t e r s t o de-

This t e s t w i l l be performed a t t h e normal,

termine t h e i r e f f i c i e n c y . operating flow conditions.

B r i e f l y t h e DOP smoke t e s t c o n s i s t s of i n t r o -

ducing d i o c t y l p h t h a l a t e smoke upstream of t h e f i l t e r s , taking a i r samples on both s i d e s of t h e f i l t e r s and determining t h e percentage of t h e smoke removed by t h e f i l t e r s .

This t e s t i s described i n Section 3F, P a r t V I I I ,

Operating Procedures and i n ORNL-3442, "Tests of High E f f i c i e n c y F i l t e r s and F i l t e r I n s t a l l a t i o n s a t ORNL." 2.3.15.2

Stgngbx

Fa2 &grgt&og

The design of t h e stack-fan c o n t r o l system i s such t h a t if Fan No. 1

or i t s discharge damper should f a i l , r e s u l t i n g i n a pressure r i s e (less negative) i n t h e s u c t i o n l i n e , Fan No. 2 will be s t a r t e d automatically t o maintain v e n t i l a t i o n .

The operation of t h e system w i l l be thoroughly

t e s t e d and t h e c o n t r o l s set t o s t a r t Fan No. 2 when t h e p r e s s u r e i n t h e main v e n t i l a t i o n header rises above l i m i t s .

This t e s t i s described i n

d e t a i l i n Section 4F, P a r t V I I I , Operating Procedures.

2.3.15.3

Stack-Flow-Indicator-Cal~b~ation

The stack-flow i n d i c a t o r w i l l be c a l i b r a t e d s o t h a t t h e amount of a c t i v i t y r e l e a s e d can be determined.

The flow i n d i c a t o r w i l l a l s o provide

information regarding t h e condition of t h e a b s o l u t e f i l t e r s .

Details of

t h i s c a l i b r a t i o n are given i n Test Memo X I 2.3.15.3. 2.3.15.4

~~gr-a~d-Valve-Set4i~g~

The dampers and v e n t i l a t i o n - c o n t r o l valves w i l l be s e t f o r normal

operation as described i n Section 4F, P a r t V I I I , Operating Procedures. A l l v e n t i l a t e d a r e a s w i l l be checked f o r adequate v e n t i l a t i o n .

The e f f e c t

on t h e v e n t i l a t i o n i n various areas caused by operating dampers or doors

2-24 J

w i l l be checked.

I n s t a l l e d and supplementary p o r t a b l e instruments w i l l

be used i n making t h e s e tests.

Details of t h e s e t e s t s are given i n

Test Memo X I 2.3.15.4. 2.3.15.5

ifighzEay-&a&as

During maintenance, when t h e r e a c t o r c e l l and drain-tank c e l l are open, and during p o s s i b l e accidents, t h e high bay i s considered as secondary containment.

Excessive leakage i n t h e high bay could prevent keeping t h e

area a t a negative p r e s s u r e when t h e v e n t i l a t i n g system i s operating. A l s o upon l o s s of t h e s t a c k f a n s during an accident, excessive leakage

The

could cause contamination of t h e b u i l d i n g and surrounding area.

leakage i n t o t h e high bay w i l l be measured by c l o s i n g a l l i n l e t vents and doors and a l l e x i t vents except one wnich l e a d s t o t h e s t a c k .

The one

vent w i l l be t h r o t t l e d t o give t h e d e s i r e d negative p r e s s u r e i n t h e high bay and the flow measured w i t h p o r t a b l e instruments.

Details are given

i n Test Memo X i 2.3.15.5. 2.3.16

Liquid-Waste System

The liquid-waste system i s used t o t r a n s f e r and s t o r e aqueous waste m a t e r i a l which may contain r a d i o a c t i v i t y or beryllium.

This l i q u i d waste

i s pumped p e r i o d i c a l l y t o the Melton Valley waste-handling system.

The

liquid-waste system i s a l s o used f o r c l a r i f y i n g s h i e l d i n g water used i n t h e decontamination c e l l and tank.

P r e c r i t i c a l t e s t i n g w i l l c o n s i s t of

t h e following items. 2.3.16.1

Lezk-TgsLil2g

I n order t o a s s u r e t h a t none of t h e tanks, c e l l s , and piping leak, they w i l l be f i l l e d with water and p h y s i c a l l y observed or w i l l be p h y s i c a l l y checked during o t h e r tests described below.

o r hydrostatic t e s t s a r e projected.

No pneumatic

Details a r e given i n Test Memo

XI 12.3.16.1. 2.3.16.2

T a ~ k - C a l - i b r a 4 i g n - a ~ d - W ~ sFlow-Rates ~e~~~

To f a c i l i t a t e f u t u r e c a l c u l a t i o n s of t h e amount of a c t i v i t y p r e s e n t and t h e amount of c a u s t i c necessary f o r n e u t r a l i z a t i o n , t h e waste-tank volume w i l l be c a l i b r a t e d

the level indicator.

The waste pump w i l l be

c a l i b r a t e d t o determine t h e flow r a t e E discharge p r e s s u r e . given i n Test Memo X I 12.3.16.2

Details a r e

2- 25 V

wagte F i l t e r

2.3,16.3

To determine t h e proper operating conditions f o r t h e waste f i l t e r , shake down t e s t s w i l l be made. 2.3.16.4

Details a r e given i n Test Memo X I 2.3.16.3.

x r a n g f p - t g geLtgn-VglLe2

waste s y s tem

Several p r a c t i c e runs w i l l be made t o t e s t t h e a b i l i t y t o t r a n s f e r waste t o t h e Melton Valley waste system.

Procedures given i n Section 3,

P a r t V I I I , Operating Procedures w i l l be followed. 2.3.17

Samplers

Fgl, C o o l a n t , _ a n d - ~ e l - _ c ~ s ~ i n g ~ S ~ S sa ~ g lee~r s

2.3.17.1

The f u e l and coolant s a l t samplers of t h e MSRE were developed and

t e s t e d by t h e Development Section of t h e Reactor Division and a r e described i n ORNL semiannual progress r e p o r t s from 1961 t o 1965.

The

only t e s t i n g on s i t e w i l l be t h e equipment l e a k check and o p e r a t i o n a l t e s t s of t h e assembled u n i t during operator t r a i n i n g . 2.3.17.2

Grgp&i~e-Sgm@~

The removal of g r a p h i t e and INOR-8samples from t h e r e a c t o r core w i l l be t e s t e d by using remote procedures before going i n t o power operation. The procedure t o be used i s Remote Maintenance Procedure No. 21, P a r t X,

Maintenance Equipment and Procedures. 2.3.17.3

Qffggs-Sa-mEling

The offgas sampling system c o n s i s t s of i n - l i n e conductivity measurements and a chromatograph and a l s o c e l l s f o r l i q u i f y i n g and removing samples i n s h i e l d e d containers.

This system i s being designed by t h e

Reactor-Division Development Section and w i l l be 'bench t e s t e d before installation.

The system w i l l a l s o be checked a f t e r i n s t a l l a t i o n by

a d d i t i o n of known mixtures of gases f o r t e s t i n g and c a l i b r a t i o n . 2.3.18

Control Rods

The t h r e e c o n t r o l rods used i n t h e PERE were designed and thoroughly t e s t e d by t h e Reactor-Division Development Section before d e l i v e r y t o t h e MSRE.

A f t e r i n s t a l l a t i o n they w i l l be t e s t e d t o a s s u r e t h a t they function

properly.

*E . C . Hise W

and R . Blumberg, MSRE Design and Operations Report, P a r t X, Maintenance Equipment and Procedures, USAEC Report ORNL-TM-910, Oak Ridge National Laboratory, i n preparatlon.

2-26

2.3.18.1

gate-of

Fail

The rate of f a l l of each c o n t r o l rod will be used as a guide t o t h e mechanical condition of t h e rod.

The drop time, which i s l e s s than one

second, will be t e s t e d as described i n Test Memo X I 2.3.18.1.

2.3.18.2

zogi&ign-Ind&cator

The p o s i t i o n of each c o n t r o l rod i s i n d i c a t e d by syncro p o s i t i o n indicators.

The lower p o s i t i o n s of t h e rods are a l s o i n d i c a t e d by changes

i n back pressure on t h e component coolant a i r as each rod passes through a restriction.

This i s c a l l e d t h e f i d u c i a l zero.

The syncro p o s i t i o n

i n d i c a t i o n will be checked a g a i n s t t h e f i d u c i a l zero f o r each rod.

Future

periodic checks of t h i s r e l a t i o n s h i p w i l l provide information about poss i b l e s t r e t c h i n g of t h e rod mechanism o r o t h e r d i f f i c u l t i e s .

2.3.19 Heaters E l e c t r i c h e a t e r s a r e provided f o r a l l p a r t s of t h e systems, i n order t o preheat a l l components before t h e additioll of t h e s a l t and t o maintain the temperature of t h e s a l t during zero-power operation. 2.3.19.1

I ns ta ll atio -n

To permit proper operation and maintenance, t h e l o c a t i o n of each h e a t e r must be known as well as the r o a t i n g of t h e power l e a d s through t h e breakers, c o n t r o l l e r s , junction boxes, and disconnects.

Tests w i l l

be made during construction and p r e c r i t i c a l t e s t i n g t o a s c e r t a i n t h a t these a r e i n s t a l l e d as designed.

Measurements w i l l be taken of t h e

h e a t e r - c i r c u i t r e s i s t a n c e , t h e r e s i s t a n c e t o ground, and t h e thermocouple response,

The d e t a i l s of these tests f o r t h e r e a c t o r c e l l a r e given i n

T e s t Memo X I 2.3.19.1-A,

f o r t h e drain-tank c e l l i n Test Memo X I 2.3.19.l-B,

and f o r t h e coolant c e l l i n Test Memo X I 2.3.19.1-C. 2.3.19.2

_ P o ~ Eegu&aLign-and-@x&mgr-Sgtting y

Control of the e l e c t r i c a l input t o t h e h e a t e r s i s e n t i r e l y manual, i n response t o system temperature. voltage c o n t r o l l e r s a r e used.

Powerstat and induction-regulator

Since t h e h e a t e r s have excess i n s t a l l e d

capacity, t h e powerstats w i l l be provided with nechanical s t o p s and t h e induction-regJlator l i m i t switches w i l l be a d j u s t e d t o l i m i t t h e system temperature t o 1300째F o r below.

Duririg t h e f i r s t few heatups of t h e

2- 27

systems the s e t t i n g s and the ammeter readi9gs of each c o n t r o l l e r w i l l be determined. X i 2.3.2.2-B,

2.3.20

The d e t a i i s of these t e s t s a r e given i n Test Memos X I 2.3.l.l-B, and X I 2.3.3.1-B.

Freeze Valves

The f r e e z e valves were t e s t e d by the Development Section of the Rea c t o r Division p r i o r t o i n s t a l l a t i o n .

On-site t e s t i n g w i l l c o n s i s t of

a d j u s t i n g h e a t e r s e t t i n g s and a i r loadings t o give t h e proper thawing and f r e e z i n g c h a r a c t e r i s t i c s f o r each freeze valve. 2.3.21

Miscellaneous

2.3.21.1

_Leak-C&eck-of

gq@gmgnL and

pigix

P r i o r t o c r i t i c a l operation, a l l process piping and equipment must be essentially leak tight.

Other piping not d i r e c t l y connected t o s a l t l i n e s

must not l e a k excessively.

Testing w i l l s t a r t with components as they a r e

completed and w i l l continue throughout construction and e a r l y operation. The following i s a d e s c r i p t i o n of t h e t e s t s which w i l l be performed. S a l t Piping - All r e a c t o r - c e l l ,

drain-tank-cell,

fuel-processing-cell,

and c o o l a n t - c e l l piping and equipment which i s prefabricated and assembled outside t h e c e l l s w i l l be evacuated and given a standard helium l e a k t e s t to

cc of helium per second.

A l l s a l t piping and welds n o t t e s t e d

before i n s t a l l a t i o n w i l l be pressurized with helium a f t e r i n s t a l l a t i o n , To increase t h e s e n s i t i v i t y , the s e c t i o n s t o

and l e a k t e s t e d i n the c e l l .

be l e a k checked w i l l be sealed i n p l a s t i c , and the i n s i d e of the p l a s t i c w i l l be szrveyed w i t h a helium l e a k d e t e c t o r .

Any indicated leakage w i l l

be l o c a t e d and repaired.

Auxiliary Systems

- Both

i n - c e l l and o u t - o f - c e l l equipment and

piping w i l l be pressurized and soap checked or helium l e a k t e s t e d .

a d d i t i o n t o the pressure t e s t t h e cover-gas system w i l l be checked t o a s s u r e t h a t t h e r e are no leaks which would allow back d i f f u s i o n of moisture i n t o t h e cover-gas system.

An increase i n moisture between the t r e a t i n g

s t a t i o n and t h e c e l l penetrations would be an i n d i c a t i o n of t h i s . Both i n - c e l l and o u t - o f - c e l l t r e a t e r - w a t e r piping w i l l be hydros t a t i c a l l y t e s t e d f o r leaks. t h i s test.

The thermal s h i e l d w i l l be valved o f f during

All spool pieces between sections of t h e thermal s h i e l d w i l l

be helium l e a k t e s t e d Sefore i n s t a l l a t i o n , and a11 f i e l d welds which connect t o the thermal s h i e l d w i l l be x-rayed t o ensure t h a t no leaks e x i s t .

2- 28 The leak-detector headers w i l l be p r e s s u r i z e d t o 125 p s i g and obLeaks w i l l be l o c a t e d by soap

served f o r time-dependent pressure drop. testing.

The leak-detector l i n e s w i l l be assumed t o be l e a k t i g h t u n l e s s

t h e closure monitored by any l e a k d e t e c t o r cannot meet s a t i s f a c t o r y l e a k rates.

If t h e l e a k i s not l o c a t e d a t t h e flanged j o i n t , t h e l e a k - d e t e c t o r

l i n e w i l l be inspected. Lines and equipment i n t h e s e systems w i l l be t e s t e d by soap t e s t i n g . 2.3.21.2

gx&exngl-Souyce Megsurgrng.3

The E R E w i l l use an e x t e r n a l neutron source of curium and americium. This source w i l l be l o c a t e d outside t h e r e a c t o r and on t h e opposite s i d e

from t h e neutron-detecting instruments.

The source has t o be of s u f f i c i e n t

s t r e n g t h t o give a f i n i t e reading on t h e wide-range counting channels with t h e r e a c t o r empty.

To properly s i z e t h e neutron source t o be used

during operation, an a v a i l a b l e source of known s t r e n g t h w i l l be used t o o b t a i n preliminary readings with t h e r e a c t o r empty before f a b r i c a t i n g a source f o r t h e r e a c t o r . 2.3.22

Details a r e given i n Test Memo X I 2.3.21.2.

E n t i r e Plant

When construction i s complete, t h e e n t i r e i n t e g r a t e d p l a n t w i l l be operated t o t e s t every aspect of t h e r e a c t o r except t h e nuclear behavior. A number of t h e t e s t s described above f o r t h e various systems r e q u i r e t h e

e n t i r e p l a n t t o be i n operation.

These w i l l be completed a t t h a t t i m e .

Oxygen w i l l be purged from t h e equipment and t h e e n t i r e system tested t o a s s u r e t h a t it i s l e a k t i g h t . A rN.m-ber of normal s t a r t u p s and runs w i l l be made t o c o r r e c t e r r o r s

i n operating procedures, check adequacy of t h e i n t e g r a t e d design, shake down equipment, and t r a i n operating personnel. When operation i s reasonably s t a b l e and equipment and instrument a t i o n a r e functioning properly, tests w i l l be made t o determine t h e e f f e c t of o t h e r operating conditions o r modes.

Faseline data w i l l be ob-

tained; adequacy of instrumentation w i l l be checked; thermocouple b i a s e s w i l l be determined; and inventory methods w i l l be evaluated.

Several heat

balances w i l l be taken and a t least one r o u t i n e pressure t e s t w i l l be made. Fuel- and coolant-system samples w i l l be taken t o t e s t t h e operation o f t h e samplers and t o i n v e s t i g a t e inleakage of oxygen and o t h e r contaminants o r changes i n t h e composition of t h e s a l t . samplers w i l l be t e s t e d .

S a l t a d d i t i o n s using t h e

2- 29

A t t h e end of t h e s e r i e s of i n t e g r a t e d runs, samples o f the g r a p h i t e

w i l l be removed t o determine s a l t permeation and p h y s i c a l damage. Before adding t h e f'uel, i n t e r n a l and e x t e r n a l examinations will be made f o r i n d i c a t i o n s of excessive w e a r o r corrosion.

A l l i n - c e l l modifi-

c a t i o n s and r e p a i r s w i l l be completed before c r i t i c a l i t y .

-tails

of these i n t e g r a t e d runs w i l l be given i n t h e d a i l y s h i f t

i n s t r u c t i o n s and i n the run i n s t r u c t i o n s . gegt-&lance

2.3.22.1

Heat balances w i l l be made on t h e MSRE system t o determine t h e thermal power t h a t i s generated and t o provide a check on t h e o t h e r methods of i n d i c a t i n g power. The h e a t balance w i l l be made by considering t h e r e a c t o r c e l l and t h e drain-tank c e l l as an envelope and measuring a l l the energy t h a t i s

added t o or taken from t h i s envelope, t h e n e t energy removed being t h e thermal power generated by t h e r e a c t o r . There w i l l be some heat sources and s i n k s t h a t w i l l be small and t h e r e f o r e not evaluated, i . e . h e a t removed by t h e cover-gas system and h e a t removed by keeping c e l l pressure below atmospheric are n e g l i g i b l y

small.

There w i l l be others, e s p e c i a l l y heat sinks, t h a t cannot be

measured d i r e c t l y and are not i n d i v i d u a l l y included i n t h e evaluation a These terms a r e evaluated c o l l e c t i v e l y i n a c o r r e c t i o n term c a l l e d "heat

losses.

A t a t i m e when the system i s hot and c i r c u l a t i n g but no power i s

being produced an evaluation of t h e h e a t - l o s s t e r m can be made.

This

may be accomplished by measuring t h e energy added t o t h e envelope by heaters, f u e l - c i r c u l a t i n g pump, space-cooler motors, e t c . , and t h e energy removed by cooling water, cooling s a l t , cooling o i l , cooling a i r , e t c . ; t h e difference between t h e s e two energy t a b u l a t i o n s w i l l be t h e t e r m i n question.

This term will be evaluated s e v e r a l times both before and

a f t e r power operation has begun.

By t h e time t h i s measurement has been

made s e v e r a l times t h e value should be known w i t h good s t a t i s t i c a l confidence

The h e a t balance w i l l be c a l c u l a t e d p e r i o d i c a l l y (normally, every

4 hours)

by t h e on-line computer.

Hand c a l c u l a t i o n s of t h e h e a t balance

will be made f o r comparison with computer r e s u l t s .

The d e t a i l s of t h e

method used for c a l c u l a t i n g a heat balance are e s s e n t i a l l y the same for both the manual and computerized approaches. i n T e s t Memo 2.3.22.4.

These details a r e described

SECTYON 3 ZERO POWER EXPERIMEYPS

3.1 OBJECTIVES A f t e r t h e non-nuclear operation of t h e r e a c t o r system has been adequately demonstrated, a program w i l l be started whose u l t i m a t e ob-

jective i s the operation of t h e r e a c t o r a t full power. phase of t h i s program i s

The i n i t i a l

s e r i e s of experiments t o e s t a b l i s h t h e basic

nuclear and related c h a r a c t e r i s t i c s of the system a t e s s e n t i a l l y zero power.

The a c t u a l power l e v e l f o r these experiments can not be p r e c i s e l y

defined because accurate power c a l i b r a t i o n s w i l l not be a v a i l a b l e u n t i l

after t h e system has operated a t s u b s t a n t i a l powers.

I n general, t h e

power l e v e l during t h i s phase of the operation will be a few watts w i t h

a l i m i t of about 10 kw.

(The power w i l l be kept low t o minimize the

a c t i v i t y of the f u e l i n the shutdown preceding power o p e r a t i o n . )

The first of these experiments i s the i n i t i a l c r i t i c a l experiment. During t h i s experiment, enriched uranium i n concentrated form w i l l be added t o the f u e l c a r r i e r s a l t i n a c a r e f u l l y c o n t r o l l e d manner t o bring

the

23%

concentration up t o the m i n i m u m required f o r c r i t i c a l i t y a t

lX#)"F (na c i r c u l a t i o n , rods f u l l y withdrawn).

One purpose i s t o check

the c a l c u l a t i o n s of c l e a n c r i t i c a l concentration.

Preliminary informa-

t i o n on the concentration c o e f f i c i e n t of r e a c t i v i t y and the e f f e c t s of c i r c u l a t i o n w i l l a l s o be obtained. l i s h e d i n t h i s experiment, the

F i n a l l y , from t h e base p o i n t estab-

"3 a d d i t i o n s

necessary t o b r i n g the

concentration up t o t h e operating l e v e l can be made w i t h confidence. The a d d i t i o n s of f u e l t o e s t a b l i s h the operating concentration w i l l be used t o compensate f o r control-rod i n s e r t i o n i n experiments t o est a b l i s h rod worths as functions of p o s i t i o n , temperature, uranium con-

centration, and pressure.

I n a d d i t i o n measurements w i l l be made t o

evaluate the r e a c t i v i t y c o e f f i c i e n t s of the various parameters.

Enough

enriched uranium w i l l . be added i n these experiments t o permit c a l i b r a t i o n of one c o n t r o l rod over i t s e n t i r e range of t r a v e l . Numerous samples of the f u e l s a l t w i l l be analyzed during t h e course of t h e uranium a d d i t i o n s .

The primary purpose i s v e r i f i c a t i o n

3 -2 of the uranium concentration at each point in the experiment, but the samples will also yield valuable data on salt composition and corrosion.

An extensive dynamics testing program will be started during this phase of the operation. The purpose.of this program is to investigate system stability and to obtain information about the reactor that is not available otherwise from static measurements. The separate tmperature coefficients of reactivity of the fuel and the graphite, f o r example, could not be determined from static measurements. However, since the transient temperature response characteristics of the fuel salt and the graphite moderator are quite different (the graphite temperature responding much slower), a dynamic measurement may be analyzed such that the two effects can be isolated. &termination of other important reactor parameters, such as coefficients of fuel-to-graphiteheat transfer, and heat exchanger, radiator, and piping heat transfer coefficients will also be attempted by dynamic tests. Another function of these tests is to determine the forms of mathematical models which adequately describe the transient behavior of the system. Noise analyses will also be made of the neutron flux to evaluate the mechanisms causing random perturbations in reactivity. 3.2 PROCEWRES

3.2.1

Initial Critical Experiment This experiment basically consists of adding increments of enriched

uranium concentrate to the fuel salt mixture and observing the progress toward the critical concentration by the increased source multiplication. Successive additions of kilogram quantities of 23%J

to the salt in the

drain tanks, followed each time by a fill of the core and multiplication measurements, w i l l comprise about 98 percent of the critical amount

(69 kg

23â&#x20AC;?v>.

The remainder will be added in 85-g batches through the

sampler-enricher. A removable external source (241Am-242Cm-Be) emitting lo9 n/sec will

be used.

(In the later stages the alpha-n source in the fuel salt will

3- 3 e n t e r i n t o the experimental p r o c e h r e . )

w i l l be used:

FOW

neutron counting channels

two f i s s i o n chambers in the instrument shaft, a IF3

chamber i n the instrument shaft, and another EF3 chamber i n t h e thermal shield

A t the beginning of the experiment, d r a i n tank 2 (FD-2) will contain

s a l t lacking only t h e a d d i t i o n of enriched uranium concentrate t o reach the s p e c i f i e d operating composition.

The enriched concentrate (molar

composition, 7346 LiF-27% UF4, i n which the uranium i s 93% 23%)

can be

added d i r e c t l y t o FE-2 from storage cans, each containing 1 5 kg of 23%.

The amount added from a can can be p o s i t i v e l y l i m i t e d by a d j u s t -

ment of a dip tube. The temperature of the core w i l l be maintained a t 1200Â°F throughout the experiment.

Except f o r the very l a s t step, the count r a t e s used i n

p r e d i c t i n g the c r i t i c a l condition w i l l be taken with a l l withdrawn t o t h e i r upper limits.

3 c o n t r o l rods

The rods w i l l be p a r t i a l l y i n s e r t e d

while the s a l t l e v e l i s r i s i n g i n t h e core and while uranium i s being added through the sampler-enricher and w i l l be f u l l y i n s e r t e d when the f u e l c i r c u l a t i n g pump i s being s t a r t e d . Reference count r a t e s w i l l be determined with the barren s a l t a t l e v e l s i n the core and with the r e a c t o r vessel f u l l . the r e a c t o r following an a d d i t i o n of 23%

w i l l be measured a t these same l e v e l s .

During each f i l l of

i n the d r a i n tank, count r a t e s

Count r a t e s w i l l a l s o be measured

w i t h barren s a l t c i r c u l a t i n g , when the core densfty is reduced by the

presence of entrained gas. The f i r s t a d d i t i o n of enriched concentrate t o FD-2 w i l l contain

45 kg of â&#x20AC;&#x153;â&#x20AC;&#x2122;5, o r 64% of the predicted c r i t i c a l amount.

The s i z e s of

l a t e r a d d i t i o n s through FD-2 w i l l be s p e c i f i e d on the b a s i s of extrapol a t i o n of p l o t s of inverse count r a t e s E amount of 23%

i n t h e salt.

The i n t e n t i o n is t o make four additions through FD-2, bringing t h e concentration t o

23%

64, 87, 94, and 98s of the minimum c r i t i c a l value.

After count r a t e s have been measured with the salt l e v e l s i n the r e a c t o r vessel, the loop w i l l be f i l l e d and c i r c u l a t e d ,

The purpose i n

t h i s i s t o insure complete mfxing, t o obtain samples Per uranium a n a l y s i s

from the pump bowl, and t o observe the r e a c t i v i t y e f f e c t s of c i r c u l a t i o n

3- 4 (loss of delayed neutrons and entrainment of gas i n t h e c i r c u l a t i n g

s a l t ) . After the t h i r d and f o u r t h a d d i t i o n s , t h e e x t e r n a l source w i l l be temporarily removed, t o permit observation of t h e m u l t i p l i c a t i o n of the i n t e r n a l source. When the count rate p l o t s show t h a t the 23%

inventory i s l e s s than

1 . 5 kg below t h e c r i t i c a l loading (expected a f t e r t h e f o u r t h a d d i t i o n through FD-2), t h e remainder of t h e concentrate w i l l be added through t h e sampler-enricher. k r i n g t h e a d d i t i o n of t h e remaining

23%

i n 65-g increments,

count r a t e s will be determined a t i n t e r v a l s w i t h c i r c u l a t i o n stopped and t h e rods f u l l y withdrawn.

P l o t s of inverse count rate

23%

concen-

t r a t i o n will be used t o e x t r a p o l a t e t o the c r i t i c a l p o i n t f o r these conditions.

A s an a i d t o t h i s extrapolation, count r a t e s w i l l be

each 85-g

measured w i t h t h e s a l t c i r c u l a t i n g a f t e r

made.

a d d i t i o n and p l o t s

(The c i r c u l a t i n g p o i n t s w i l l be displaced i n k from t h e non-

c i r c u l a t i n g p o i n t s because of the delayed neutron and e n t r a i n e d gas effects. ) Count rates will be measured both w i t h t h e e x t e r n a l source and without it.

The count rates without t h e e x t e r n a l source w i l l be used

l a t e r t o evaluate the i n t e r n a l alpha-n source ( a f t e r count r a t e - f i s s i o n

rate c o r r e l a t i o n s have been e s t a b l i s h e d )

When t h e e x t r a p o l a t i o n s i n d i c a t e t h a t one more capsule will raise the

â&#x20AC;&#x2DC;IJ%

concentration above t h e minimum c r i t i c a l value, t h e increment

w i l l be added, c i r c u l a t i o n w i l l be stopped, and t h e r e a c t o r made c r i t i c a l

by rod withdrawal. 3.2.2

C a l i b r a t i o n of Control Rods The t h e o r e t i c a l l y d e s i r a b l e o b j e c t i v e

of t h e c o n t r o l - r o d c a l i b r a -

t i o n experiments i s t o measure t h e r e a c t i v i t y worth of each rod as a f u n c t i o n of t h e p o s i t i o n s of t h e o t h e r two rods, the uranium concentrat i o n i n the salt, t h e core temperature, f i s s i o n - p r o d u c t poison d i s t r i bution, and the volume of e n t r a i n e d gas in the s a l t ,

I n the p r a c t i c a l

sense, s e p a r a t i o n of s e v e r a l of these effects i P d i f f i c u l t , and some compromise has t o be made i n determining t h e effects most important t o t h e MSRE operation.

Because of t h e f l u i d nature of the f u e l and the fact

3- 5 that, once added t o t h e salt, removal of uranium i s inconvenient, the b a s i s f o r the experimental work r e l a t i n g t o rod c a l i b r a t i o n must be t h e s e q u e n t i a l a d d i t i o n of uranium leading t o t h e amaunt required f o r f u l l I n general, therefore, a f t e r a s p e c i f i e d uranium

power operation.

a d d i t i o n the experiments w i l l be designed t o measure the e f f e c t s of the important v a r i a b l e s o t h e r than uranium concentration on r e a c t i v i t y and control-rod worth and t o provide experimental c r o s s checks on the measured worth a t t h e new concentration. Several considerations e n t e r i n t o the s p e c i f i c design of the rod c a l i b r a t i o n experiments.

It i s a n t i c i p a t e d t h a t during normal operation

of the r e a c t o r a l l t h r e e c o n t r o l rods w i l l be p a r t l y i n s e r t e d .

The two

shim rods w i l l be s t a t i o n a r y , except f o r occasional adjustments following power changes.

The regulating rod may be driven up and down f o r s h o r t

distances r a t h e r frequently as t h e servo c o n t r o l l e r holds the power o r temperature a t the s e t p o i n t .

Present plans a r e t o keep the shim rods

well above the r e g u l a t i n g rod during normal operation.

The reason i s

t h a t i f the rods were kept a t about the same l e v e l , t h e r e would be sharp

changes i n regulating-rad s e n s i t i v i t y as the regulating rod moved i n t o and o u t of t h e shadow of the nearby rods.

I n a d d i t i o n t o operating the

r e g u l a t i n g rod out of the shim rod shadow, it w i l l be p r a c t i c a l t o require t h a t the shim rods always be held a t n e a r l y equal p o s i t i o n s . The maximum amount of uranium t o be added t o the f u e l salt i s that amount required t o a t t a i n full power operation, with maximum poisoning and burnup occurring when a l l rods care'withdrawn t o the l i m i t s of their operating ranges.

Since this m o u n t depends on t h e xenon poisoning and

s e v e r a l o t h e r e f f e c t s which w i l l not be known w i t h p r e c i s i o n i n advance

of the approach-to-power

tests, t h e maucirmun uranium added t o t h e salt

w i l l be i n i t i a l l y l i m i t e d t o the m o u n t required t o c a l i b r a t e one rod

over i t s e n t i r e length with t h e o t h e r two rod6 f u l l y withdrawn (-2.3$ CUr/k).

More uranium will be added and the s o d c a l i b r a t i o n s continued

i f it proves necessary during the approach-to-power t e s t s .

The general techniques which w i l l be used i n the c a l i b r a t i o n experiments will be rod bump-stable period measurements t o obtain d i f f e r e n t i a l V

worth data f o r a s i n g l e rod w i t h t h e o t h e r two r o d s held a t f i x e d p o s i t i o n s , and rod d r o p - s u b c r i t i c a l counting r a t e measurements t o o b t a i n t h e i n t e g r a l worth df a s p e c i f i c rod c o n f i g u r a t i o n .

The sequence of measurements i n the rod c a l i b r a t i o n experiments i s

expected t o be as follows.

An i n i t i a l series of uranium a d d i t i o n s t o

the f u e l s a l t w i l l be made t o b r i n g t h e r e a c t o r c r i t i c a l w i t h t h e f u e l

s t a t i o n a r y a t the nominal operating temperature of 1200째F, and w i t h a l l three rods f u l l y withdrawn.

I n subsequent c a l i b r a t i o n tests, the ex-

t e r n a l neutron source w i l l be r e i n s e r t e d i n order t o provide s i g n i f i c a n t counting r a t e s i n s u b c r i t i c a l measurements.

With t h e i n i t i a l condition

of rods f u l l y withdrawn and the neutron l e v e l high enough t o make t h e c o n t r i b u t i o n from t h e e x t e r n a l source n e g l i g i b l e (-10 watts), one of the rods w i l l be dropped with t h e o t h e r two held fixed, and t h e sub-

c r i t i c a l counting r a t e w i l l be measured as a f u n c t i o n of t i m e .

The

rod w i l l then be withdrawn again and t h e measurement repeated by dropping another of t h e three rods.

A f t e r t h e i n d i v i d u a l worth

of each of

t h e t h r e e rods has been measured, t h e rods w i l l be dropped i n succession and then as a group t o determine t h e cumulative worth. Upon completion of t h e i n i t i a l rod-drop tests, c i r c u l a t i o n w i l l be e s t a b l i s h e d and small a d d i t i o n s of highly enriched uranium t o t h e s a l t w i l l be made by dissolukdon i n t h e pump bowl.

The t o t a l amount added

will be t h a t required t o r e a t t a i n c r i t i c a l i t y w i t h one r o d i n s e r t e d a

small d i s t a n c e i n the core (approximately 10% of t o t a l i n s e r t i o n ) .

With

t h e core c r i t i c a l and the f u e l s t a t i o n a r y a t 1200째F, rod-bump measurements w i l l be made by moving t h e rod upward a small d i s t a n c e from the c r i t i c a l p o s i t i o n and observing t h e s t a b l e r e a c t o r p e r i o d which ensues.

It i s a n t i c i p a t e d t h a t p r a c t i c a l s t a b l e periods f o r t h e s e t e s t s w i l l range from a lower l i m i t of 30 seconds t o an upper l i m i t determined by t h e u n c e r t a i n t i e s i n the rod p o s i t i o n s . A f t e r t h e f i r s t rod-bump measurements a r e completed, t h e c i r c u l a t i n g pump w i l l be s t a r t e d and t h e change i n rod p o s i t i o n r e q u i r e d t o r e a t t a i n c r i t i c a l i t y w i l l be determined.

With the f u e l c i r c u l a t i n g a t t h e i s o -

thermal temperature of 1200째F, t h e rod bump-stationary p e r i o d measurement

w i l l again be made.

3- 7 The sequence of t e s t s involving uranium addition, period measurement with fie1 s t a t i o n e r y , and period measurement with fuel c i r c u l a t i n g w i l l be repeated f o r s e v e r a l addftions of uranium u n t i l the rod being c a l i -

b r a t e d is i n s e r t e d a p p r o x h a t e l y 25% of i t s t o t a l t r a v e l .

A t this

point, with the f u e l s t a t i o n a r y t h e rod bump-period measurement w i l l be '

repeated f o r the o t h e r two rods, each time with two of the rods f u l l y withdmwn and one rod i n s e r t e d t o a t t a i n c r i t i c a l i t y ,

Also a t t h i s

point, c a l i b r a t i o n measurements f o r one rod a t intermediate i n s e r t i o n p o s i t i o n s of t h e o t h e r two rods w i l l be i n i t i a t e d .

For example, a

c r i t i c a l configuration wlll be obtained with the two shim rods i n s e r t e d equal, small distances i n the core, somewhat l e s s than the rod being c a l i b r a t e d , and the rod bump-period measurements w i l l be repeated, Upon completion of the above t e s t s , rod drop measurements w i l l be repeated f o r t h i s intermediate uranium concentration.

F i r s t , the

p a r t i a l l y i n s e r t e d rod w i l l be dropped while the other two remain f u l l y withdrawn.

Then the rods w i l l again be dropped i n succession.

For the next t e s t i n the s e r i e s of the c a l i b r a t i o n experiments a t the s p e c i f i e d intermediate uranium concentration, the isothermal temperat u r e of %he system dll be varied by manipulation of the e x t e r n a l heating elements on the c i r c u l a t i n g loop.

This experiment w i l l be l i m i t e d t o a

range of approximately 11QO"F t o 1250째F, which corresponds t o a calcul a t e d r e a c t i v i t y change of about

1.4$ &/k

i n the i n i t i a l MSRE f u e l .

Temperature changes produced i n t h i s manner a r e very slow, so t h a t it w i l l be p r a c t i c a l t o heat the loop u n t i l e i t h e r the rod i s withdrawn

t o i t s upper l i m i t o r t h e upper l i m i t i n g temperature i s reached.

Then

the loop w i l l be allowed t o cool slowly, and the p o s i t i o n of i n s e r t i o n

of t h e rod as a function of t h e temperature w i l l be recorded,

A t the

upper and lower l i m i t s of the temperature cycle, s t a b l e - p e r i o d and roddrop measurements w i l l again be made i n order t o determine the change i n r e a c t i v i t y worth of the rods produced by the change i n r e a c t o r temperature.

The f i n a l phase i n t h i s s e r i e s of' t e s t s w i l l provfde h f o r m a t i o n

r e l a t i n g t o the pressure c o e f f i c i e n t of r e a c t i v i t y .

I n t h i s connectfon,

the overpressure i n the pump bowl w i l l be fnereased by s e v e r a l p s i above I

t h e normal value of

5 p s i g and the s t e a d y - s t a t e c r i t i c a l rod

configuration will be recorded.

The vapor space i n the f u e l loop will

then be i s o l a t e d from t h e d r a i n tanks and t h e d r a i n tanks vented t o provide a pressure sink.

Then, w i t h the drain-tank vents closed, the i n t e r -

connection t o the f u e l loop can be reopened t o produce a r a p i d decrease i n overpressure.

The control-rod motion required t o maintain c r i t i -

c a l i t y will provide some information about t h e prompt p r e s s u r e c o e f f i c i e n t

as well as a check on t h e long-term pressure e f f e c t . The s e r i e s of measurements described above can be considered t o comprise those t e s t s which correspond t o a s u b s t a n t i a l a d d i t i o n o r uranium t o the s a l t .

of uranium a d d i t i o n s .

This s e r i e s w i l l be repeated f o r s e v e r a l sequences The terminations of these sequences a r e a n t i c i -

pated t o correspond t o i n s e r t i o n s of bo$, 5046, bo$, 75$, and loo$ of t h e rod being c a l i b r a t e d . The rod c a l i b r a t i o n program o u t l i n e d here has t h e advantages of r e q u i r i n g no s p e c i a l equipment and of providing a maximum amount of c a l i b r a t i o n data a t each s t a g e of t h e t e s t s .

A s t h e data i s accumu-

l a t e d , t h e influence of t h e important v a r i a b l e s a f f e c t i n g the r e a c t i v i t y can be separated and t h e rod worth f o r a f i x e d s e t of core conditions can be determined by i n t e g r a t i o n of t h e data. 3.2.3

Evaluation of Nuclear Parameters

Part of t h e task i n t h e zero-power control-rod c a l i b r a t i o n experiments w i l l be t o determine t h e s e p a r a t e r e a c t i v i t y c o e f f i c i e n t s corresponding t o changes i n uranium concentration, i n isothermal temperature of t h e core, i n e f f e c t i v e delayed neutron f r a c t i o n and bubble entrainment when s t e a d y - s t a t e c i r c u l a t i o n i s e s t a b l i s h e d , and i n system overpressure. A s these changes a r e introduced, t h e q u a n t i t y d i r e c t l y measured i s t h e change i n rod p o s i t i o n which compensates f o r the a s s o c i a t e d r e a c t i v i t y increment and r e s u l t s i n a new c r i t i c a l configuration.

The r e a c t i v i t y

c o e f f i c i e n t s of each v a r i a b l e must be determined by c o r r e c t i n g t h e measured r e a c t i v i t y increment f o r t h e change i n t h e t o t a l worth of t h e rod.

Thus t h e complete a n a l y s i s of t h e s e experiments r e q u i r e s an

"unwinding" of t h e data obtained from both rod bump-period measurements and t h e rod-drop measurements.

For t h e important case of uranium

a d d i t i o n i n t h e range required t o c a l i b r a t e the rods, t h e o r e t i c a l

3- 9 calculations indicate that this coupling effect will be very small. Hence the equivalent fuel addition corresponding to a given insertion of the rods should provide a reliable standard of comparison for the direct measurement techniques used in obtaining the rod worths.

3.2.4 Preliminary Studies of Eynamics A variety of dynamic tests is planned for the zero-power run for the purpose of determining system parameters, verifying mathematical models describing the reactor kinetic behavior, and measuring the characteristics of the reactivity-perturbing functions. Estensive use will be made of the on-lice computer in these tests (and throughout the dynamic testing program) for the acquisition of data. Some variations from the normal mode of operation of the computer will be required in some cases to provide the data required.

3.2.4.1 gogguslgar zests A number of non-nuclear tests will be performed during the flushing operations prior to the initial critical experiment.

These tests are

designed to produce background and reference information to be used in the analysis of subsequent experiments. Specifically, tests will be run to : 1.

determine transient salt flowrates for pump startup and coastdown;

determine the effects of the loop heaters on loop temperatures and

on nearby thermocouple readings; measure the transient thermal-response characteristics of various loop components and thermocouples; and

measure the non-nuclear background noise in the detection channels to be used for flux-noise measurements. Transient Flow Rate Measurements - Since the coolant-loop flow

rate is monitored by a venturi meter with two readout devices, a direct measurement of flow startup and coastdown can be made. Since the startup transient will be fast, however, it will be necessary to monitor the output of the flow transmitters directly, because there are two magnetic-amplifier devices between each transmitter and the computer.

3 -10 F3r t h e coastdown t e s t , it i s necessary t o have t h e loop isotkermal (as w i l l be t h e case a t zero power) s o as t o avoid thermal-convection flow.

3 e pimp speed t r a n s i e r . t s w i l l a l s o be recorded.

it will be necessary It i s expected t h a t salt

'To determine t h e fuel-loop flowrate t r a n s i a t s ,

t o e x t r a p o l a t e from coolant-loop measurements.

flowrate and pump speed will c o a s t down !'in unison" i n both loops; i f t h i s i s v e r i f i e d by coolant-loop measmements, then t h e f u e l flow c o a s t down can be determined from fuel-pump speed.

I f not, more sophisticated

calcula5ions may be required. A g m a - r a y densitometer, which w i l l be i n s t a l l e d about 8 f e e t

upstream of t h e r e a c t o r v e s s e l i n l e t , w i l l be used t o monitor t h e t r a n s i e n t e f f e c t s of pump s t a r t u p and coastdown on t h e behavior of b.ib-bles e n t r a i n e d i n t h e f u e l salt.

The densitometer outp-xb w i l l depend

on how much gas i s held up i n t h e 10073 (both s t a t i c and c i r c u l a t i n g )

a t t h e s t a r t of t h e t r a n s i e n t s .

There i s a p o s s i b i l i t y of bubbles

agglomerating i n t h e loop a f t e r a flow stoppage; t h i s may be d e t e c t e d by monitoring t h e densitometer a f t e r f l o w i s r e s t a r t e d . E f e c t s of Loop Heaters

- Steady-state

h e a t loss d a t a ( a t s e v e r a l

tzmperatures) may be u s e f u l f o r c o r r e c t i n g low-power t e s t r e s u l t s .

The

t r a n s i e n t response of c i r c u l a t i n g - l o o p s a l t ternperatures (with t h e o t h e r loop s t a t i c ) t o a change i n power of a group of h e a t e r s will i n d i c a t e t h e time response of coupling between h e a t e r s and s a l t . dozle

ir_

This w i l l be

bo5h t h e primary and secondary loops, sir.ce t h e h e a t e r s a r e

differect.

A t t h e same time, t h e t r a n s i e n t e f f e z t s of t h e h e a t e r power

changes on nearby tkcmocouple r e a d i r g s may b e mcasmzd. Temperatlxe Response Measurements ments of Trarious components

ir,

- TexperatLlre

response meas:ire-

t h e f u e l and coo1as.t loops and of t5ermo-

cou2les will b ? made by introdkci-ng ternperature pulses i n t o t h z loops. A hot-slug pulse w i l l be ictroduced i n t h e f u e l loop as I'oLLows:

achieve thermal equilibrium (as nearly as p r a c t i c a l ) with t h e f u e l loop stagnant and t h e coolant l o o p c i r c u l a t i n g a t a higher temperatxre. Tkie f d e l i n t h e h e a t exchanger will t h e n be heated t o coolant-loop tempera-hre.

Since t h e h e a t exckanger i s high i n t h e fuel loop, convecSion

3- 11 flow should be n e g l i g i b l e .

When t h e f u e l pump i s s t a r t e d , t h i s h o t t e r

f u e l s l u g w i l l pass through t h e cooler s e c t i o n s of t h e loop giving t h e temperature p u l s e .

E& measuring r e a c t o r i n l e t and o u t l e t temperatures,

i t s thermal t r a n s f e r function can be determined.

Comparison of t h e

response of t'ne thermocouple i n t h e well a t t h e r e a c t o r o u t l e t w i t h nearby thermocouples on the o u t s i d e of t h e piping w i l l i n d j c a t e the response time of t h e pipe thermocouples. A temperature pulse i n t h e coolant loop w i l l be introduced i n the

same manner; here, however, the s t a t i c coolant s a l t i n t h e heat exchanger should be cooler than t h e r e s t of t h e coolant loop, s i n c e t h e h e a t exchanger i s approximately a t t h e low p o i n t of t h e coolant loop.

Since

t h e r e i s some piping below t h e h e a t exchanger, t h e r e may be convection flow problems.

This cold-slug t e s t w i l l be used t o measure t h e r a d i a t o r

s a l t - s i d e t r a n s f e r function and t o check t h e response of t h e thermocouples on t h e pipes by comparison with those i n t h e wells a t t h e r a d i a t o r i n l e t and o u t l e t . Background Noise Measurements

- Preliminary

t e s t s w i l l be made t o

determine background l e v e l s f o r t h e low-power flux-noise measurements. A s p e c i a l flux-measurement channel t h a t was designed e s p e c i a l l y f o r

s e n s i t i v e noise measurements w i l l be used.

The d e t e c t o r w i l l be i n s e r t e d

i n a spare hole i n t h e nuclear instrument s h a f t .

Analog tape recordings

of the channel output noise w i l l be taken both with and without f u e l circulation.

Analysis of t h i s data w i l l r e v e a l any e f f e c t s of v i b r a t i o n

o r electromagnetic r a d i a t i o n t h a t w i l l be p r e s e n t i n l a t e r nuclear t e s t s . The noise output of the r e g u l a r flux-measurement channels w i l l be compared w i t h t h a t of t h e s p e c i a l noise d e t e c t o r channel.

3.2.4.2

zests

&n-Cyi&iGa,L Eeactoy

Various nuclear c h a r a c t e r i s t i c s w i l l be measured by dynamic t e s t s performed with t h e r e a c t o r c r i t i c a l .

The neutron k i n e t i c behavior w i l l

be a f f e c t e d by f u e l c i r c u l a t i o n due t o both t h e e f f e c t s of a l o s s of delayed-neutron precursors from t h e core ( i . e . a reduction i n p) and of t h e e n t r a i n e d gas i n t h e f u e l s a l t .

The t e s t s w i l l be designed t o

determine t h e s e p a r a t e e f f e c t s of each.

The e f f e c t s of fuel-loop

overpressure on r e a c t i v i t y v i a changes i n f u e l d e n s i t y w i l l a l s o be

3 -12 measured.

Determination of t h e zero-power neutron-kinetics t r a n s f e r

f u n c t i o n and of s e p a r a t e temperature c o e f f i c i e n t s of r e a c t i v i t y f o r t h e f u e l and g r a 2 h i t e will be attempted. E f f e c t s of Flow Transients on Neutron Kinetics

- One

t e s t w i l l be

made with t h e r e a c t o r c r i t i c a l , f u e l and coolant loops isothermal, f u e l loop s t a t i c , coolant loop c i r c u l a t i n g , and t h e f l u x servo c o n t r o l l e r on.

The f u e l pump w i l l t h e n be started, and t h e densitometer reading

and rod r e a c t i v i t y a d d i t i o n required t o keep t h e f l u x l e v e l constar?t

w i l l be monitored.

Assuming t h a t t h e f l u x c o n t r o l l e r keeps t h e r e a c t o r

c r i t i c a l , t h e rod r e a c t i v i t y changes w i l l be equal (and opposite) t o t h e r e a c t i v i t y e f f e c t s of c i r c u l a t i o n .

Since t h e e f f e c t s of delayed-

neutron precursor l o s s e s w i l l appear qcickly compared t o t h e more gradual buildup of voids i n t h e loop, tl?e two e f f e c t s may be separable.

After

d e n s i t y equilibrium i s a t t a i n e d , t h e f u e l pump w i l l be shut off again, and t h e rod motion monitored.

m e e f f e c t s on r e a c t i v i t y of t h e i n c r e a s e

i n f3 and of t h e bubbles f l o a t i n g up out of t h e core will t h e n be measured. The s t e a d y - s t a t e high-frequency f l u c t u a t i o n s i n d e n s i t y (as measured by t h e densitometer) are not expected t o a f f e c t t h e s t e a d y - s t a t e neutronl e v e l f l u c t u a t i o n s due t o t h e l o n ( i . e . 8-sec) f u e l residence t i m e i n t h e core, which w i l l "average out" t h e s e higher-frequency f l u c t u a t i o n s . Xeutron-level f l u c t u a t i o n s with hydrodynamic-pressure f l u c t u a t i o n s i n t h e core are expected t o be much g r e a t e r s i n c e t h e y would modulate t h e e n t i r e core gas vollune; however, t h e f d e l - s a l t p r e s s u r e cannot be monitored.

A cross power-spectral-density a n a l y s i s w i l l be nade t o

see i f t h e r e i s any c o r r e l a t i o n between t h e densitometer outpu-t and t h e neutron l e v e l . Should pockets of e n t r a i n e d voids be p r e s e n t i n t h e s t a t i c f u e l loop, s t a r t i n g t h e fuel p u ~ pmay sweep f a i r l y l a r g e void volumes i n t o t h e core.

This would show up i n t h e densitometer s i g n a l , and a few

seconds l a t e r as a negative r e a c t i v i t y pulse.

I f t h i s occurs, it may

be p o s s i b l e t o dete-Tine a r e a c t i v i t y - t o - v o i d transfer function. E f f e c t of I h e l Loop Orer-pressure on R e a c t i v i t y - A

rapid increase i n

pressure i n t h e core will compress t h e e n t r a i n e d gas, i n c r e a s e t h e f u e l density, and t h u s i n c r e a s e t h e r e a c t i v i t y .

A slow i n c r e a s e i n pmp-bowl

3 -13 pressure, however, will increase t h e d e n s i t y of t h e gas e c t r a i n e d i n t h e f u e l salt, and (assuming t h e rate of t h e gas volume entrainment i n t h e bowl i s c o n s t a n t ) w i l l result i n a n e t i n c r e a s e i n core void volume, hence a decrease i n r e a c t i v i t y .

The t r a n s i e n t c h a r a c t e r i s t i c s of t h e s e

e f f e c t s will be s t u d i e d by slowly b u i l d i n g up t h e pressure i n t h e f u e l pump bowl, t h e n quickly venting t h e bowl t o a previously vented d r a i n

tank through t h e by-pass l i n e . Zero-Power Neutron-Kinetics Measurements

- Dynamic

t e s t s w i l l be

made t o give information about t h e neutron-kinetics transient-response c h a r a c t e r i s t i c s and t r a n s f e r functions.

These experimects will involve

t r a n s i e n t s induced by s m d l changes i n control-rod p o s i t i o n .

The t e s t s

will be made both f o r stagnant f u e l and flowing f u e l . The f i r s t t e s t will be a control-rod pulse.

A t o t a l reactivity

i n s e r t i o n of no g r e a t e r t h a n 0.02% Ak/k i s considered adequate unless t h e f l u x noise l e v e l i s high.

Tnis will r e q u i r e a rod motion of 1 / 2

t o 2 inches, depending on t h e l o c a t i o n of t h e rod t i p .

Pulses ranging

from 5 seconds d u r a t i o n t o 30 seconds d u r a t i o n will be used.

A t the

end of t h e pulse, t h e r o d w i l l be returned t o i t s i n i t i a l l o c a t i o n . Tests on t h e control-rod mock-up i n d i c a t e t h a t rods can be p o s i t i o n e d with s u f f i c i e n t accuracy.

An automatic timing device w i l l c o n t r o l t h e

rod d r i v e motor f o r t h i s t e s t . Another s e t of tests w i l l use pseudo-randon binary i n p u t .

Tne

c o n t r o l rod w i l l move a p r e s e t d i s t a n c e using t h e au%omatic timing device.

The t e s t will involve a s e r i e s of rod motions i n which t h e rod

i s moved i n and out

around t h e c r i t i c a l p o s i t i o n .

The p a t t e r n of p u l s i n g

will have s p e c i a l p r o p e r t i e s t h a t will f a c i l i t a t e t h e frequency-response analysis.

The t e s t s will use pulses of 1 t o 60 seconds with r e a c t i v i t y

i n s e r t i o n s of less t h a n 0.02%. Flux noise spectrum measurements w i l l a l s o be made.

These should

give gpod information i n t h e high frequency range (1-10 cycles p e r second) where t h e t r a n s f e r f u n c t i o n r o l l - o f f occurs. r o l l - o f f i s determined by t h e valve of B/,L?*,

Since t h i s

it will f u r n i s g a d d i t i o n a l

information for separating t h e r e l a t i v e e f f e c t s of bubble c i r c u l a t i o n and precursor c i r c u l a t i o n .

3 -14 v

Determination of Separate f i e 2 and Graphite Temperature Coefficients introducing a hot-fuel-slug p u l s e i n t o t h e core

of R e a c t i v i t y -By

(as described previously), b u t with t h e r e a c t o r c r i t i c a l and on flux-servo control, t h e e f f e c t s of f u e l and g r a p h i t e temperatilre on r e a c t i v i t y m a y be determined.

The r e a c t i v i t y added by t h e rods would be equal (and

opposite) t o t h a t due t o t h e temperatiire c%anges, and t o t h e e f f e c t s of

a reduction i n j3 and void entrainment.

Since t h e s e l a s t two e f f e c t s

will have been measured previously, t h e temperature e f f e c t s may be separable.

3.2.5

Evaluation of Neutron Sources and Future Requirements of t h e External Source The e x t e r n a l source i s one i n which alpha p a r t i c l e s from americium-241

and curium-242 i n t e r a c t with b e r y l l i u m t o produce neutrons.

The source

w a s f a b r i c a t e d by encapsulating a mixture of beryllium with 2 c u r i e s of

241Am

(462-y half- l i f e ) .

It was t h e n i r r a d i a t e d for 2 1 days i n t h e ORR

t o b u i l d up about 380 c u r i e s of 242Cm (163-day h a l f - l i f e ) . source emitted about lo9 n/sec j u s t a f t e r i r r a d i a t i o n .

Toe r e s u l t i n g

Because most of

t h e neutrons come from 242Cm alphas, t h e soarce i n i t i a l l y decays with t h e 163 day h a l f - l i f e and i s expected t o become inadequate f o r -MSRE s t a r t u p requirements i n about one y e a r i f it i s not reirradiated.

The

source w i l l be exposed t o a f l u x of approximately 1 x 1 0 l 2 n/cm2 sec when t h e MSRF: i s a t 10 Mw, b u t t h i s i s not high enough t o maintain an adequate source when t h e t a r g e t i s only 2 c u r i e s of 241Am.

Tie i n t e n t i o n

i s t o i n s t a l l a new source a f t e r one year, containing enough 241A~ t a r g e t s o t h a t t h e f l u x i n t h e source tube can keep an adequate amount of 242Cx b u i l t up. Since t i e r e l i a b i l i t y of t h e f l u x c a l c x i a t i o n i s limitec?. for p o s i t i o n s f a r away from t h e core (- 20" from t h e core,

- 50"

from t h e c e n t e r of

t h e c x e ) , t h e m o u n t of An needed f o r an adequate soarce cancot be s p e c i f i e d accurately.

The high c o s t of Am (- $1600/.g) makes it d e s i r a b l e

t o s p e c i f y t h e smallest p r a c t i c a l m o u n t of Am f o r t h e permanent source. Therefore, it w i l l be neczssary t o make measurements of t h e f l u x i n t h e source txbe a t low powerm t h a t t h e u s e f u l l i f e of t h e i n i t i a l source and t h e ?j.t.Jre reqairements may be calculated.

E i s w i l l be accomplished

rrr

3-15 by withdrawing the source while the r e a c t o r i s operating a t - 10 Kw and

i n s e r t i n g an a r r a y of gold and copper f o i l s i n t o the source tube.

w i l l determine the f l u x a t t h e s p e c i f i e d power.

This

Since the f l & i s pro-

p o r t i o n a l t o power, the degree of a c t i v a t i o n of t h e Am can be c a l c u l a t e d f o r any given period of operation.

With t h i s information we can determine

the amount of Am needed t o make a source that w i l l have a minimum c o s t and a mximun p r a c t i c a l l i f e . Another* experiment plamed f o r t h i s t i m e i s the establishment of the i n t e n s i t y of the i n t e r n a l (inherent) neutron source

s a l t i n the cope.

of the clean

This w i l l be accomplished by tmasuring count r a t e s a t

various d e t e c t o r s when the r e a c t o r is only s l i g h t l y s u b c r i t i c a l , both with and without the e x t e r n a l source p r e s e n t ,

The r e l a t i o n s between

counting rates of t h e d e t e c t o r s and f i s s i o n r a t e (neutron production i n the core) w i l l be determined, a t power l e v e l s where the source c o n t r i bution is n e g l i g i b l e , by hecat balance and o t h e r c a l i b r a t i d n techniques.

These relatfms w i l l be applied to the s u b c r i t i c a l data (because t h e spatial f l u x d i s t r i b u t i o n and neutron leakage p r o b a b i l i t i e s i n the core do not change much between the high-multiplication, subcritical condition and t h e c r i t i c a l condition) %o evaluate the e f f e c t i v e , in-core neutron sources from both the e x t e r n a l and the inherent sowces.

3.2.6

Chemical Analyses During the course of t h e zero-power experiments numerous samples

of the fuel salt w i l l be analyzed for uranium. The analytical. W t a w i l l be used t o support and supplement the c a l c u l a t i o n s of u r a n i m concentrationsr

from inventory considemt%ons

'Rx! fuel solvent w i l l be sampled prcior t o the i n i t i a l c r i t i c a l

experiment both while it is

i n the d r a b tank and while it is c l r c u -

l a t i n g i n the f'uel syetem,

I n addition, many of the f u e l samples taken

during the experiments will be analyzed f o r many o t h e r constiituents besides uranim,

The eoolm% eyatem ~â&#x201A;Ź19 also be sampled,

The purpose

of this program will be t o establish m&l.yt;.LcSl base l e v e l s of c o n s t i t uents and contaminants t o compare with analyses i n subsequent stages of the MSR experiment,

3-16 Analyses wUZbe . obtatned for the component metal fluorides and

- iron,

also for the &tsrerolved m e t a l s which m u l d result from tmmsion chromium, nickel, and molyb&num. Chemical analyses will also be obtained far the =%de

c o n t e n t and the redwing power of' the salt.

must be pointed out that 131 the beginning stages of t h e experfmat, "reduehg powerf'of the s a l t should not be inferred t o r e p r e s e n t concentration of reheed uranium species bmause f i n e l y divided iron and nickel, p m b b l y p r e s e n t as impurities, c m also give rise t o "reducing powertf valtzi4si* Petrographic e m a t n a t i o n s ~ 5 1 1be ma& of f i e 1 s o l v e n t and f u e i spee5mens in the early stages of t h e zero-pmr test period to afford a baseline for o p t i c a l data s i n c e the petrographic methdl may have tmique kppllcaticm in later stages of t h e Molten-Salt Reactor Experiment *

SECTION

LOW POWER MEASUREMENTS V

4.1 OBJECTIVES After t h e zero-power experiments, t h e r e a c t o r system w i l l be shut down t o make t h e f i n a l preparations f o r operation a t s i g n i f i c a n t power levels.

These preparations w i l l include t h e hermetic s e a l i n g and t e s t i n g

of t h e secondary containment, i n s t a l l a t i o n of a l l s h i e l d i n g known t o be required, f i n a l modification and adjustment of t h e h e a t - r e j e c t i o n system, and any maintenance work which may be required.

This work w i l l be

followed by t h e next, o r low-power, phase of t h e t e s t program. The power l e v e l of t h e r e a c t o r w i l l be l i m i t e d t o about 1 Mw during t h i s phase of t h e program t o avoid most of t h e e f f e c t s of power and s t i l l permit t h e determination of t h e required information.

This

power l e v e l i s t h e point, i n r o u t i n e operation, a t which a t r a n s i t i o n

i s made from automatic c o n t r o l of t h e neutron f l u x (with independent, manual c o n t r o l of temperature) t o c o n t r o l of both temperature and f l u x . This phase of t h e operation will a f f o r d t h e first opportunity t o evaluate many of t h e power-associated c h a r a c t e r i s t i c s of t h e system. A l l of t h e s e c h a r a c t e r i s t i c s w i l l be s t u d i e d i n more d e t a i l and evalu-

a t e d more a c c u r a t e l y as t h e power l e v e l i s increased b u t t h e measurements

a t low power provide t h e information on which t h e power i n c r e a s e s a r e based. 1.

I n t h i s connection:

The b i o l o g i c a l s h i e l d i n g and containment w i l l be surveyed f o r

adequacy and t o l o c a t e area which may be of questionable adequacy a t higher powers. 2.

The nuclear power instruments w i l l be c a l i b r a t e d and a d j u s t e d t o

provide t h e d e s i r e d ranges of a p p l i c a b i l i t y .

Preliminary values w i l l be obtained f o r t h e power c o e f f i c i e n t of

reactivity.

The behavior of t h e noble gases w i l l be observed and xenon poison-

i n g w i l l be measured. I n a d d i t i o n t o t h e items mentioned above, an extensive program w i l l be p u t i n e f f e c t t o evaluate t h e nuclear, thermal, and mechanical

4.2 performance of t h e system.

Much of t h i s work w i l l make use of t h e on-

l i n e computer f o r t h e a c q u i s i t i o n and processing of d a t a .

The various

computer programs w i l l have been checked out, b u t t h i s operation w i l l permit evaluation of t h e mathematical treatments used i n t h e programs. O f p a r t i c u l a r i n t e r e s t w i l l be t h e programs which c a l c u l a t e t h e r e a c t i v i t y

balance, h e a t balance, and s a l t i n v e n t o r i e s . The experimental a n a l y s i s of t h e k i n e t i c s of t h e system, which was s t a r t e d a t zero power w i l l be continued i n a l l a r e a s where u s e f u l i n f o r mation can be gained.

The o b j e c t i v e s w i l l be e s s e n t i a l l y t h e same as

those described f o r the zero-power operation, b u t it i s expected t h a t t h e e a r l i e r parameter and model estimates can be upgraded. Samples of t h e c i r c u l a t i n g salts w i l l be removed p e r i o d i c a l l y during t h i s , as well as a l l other, phases of t h e program.

These operations w i l l

provide an opportunity t o evaluate and modify, i f necessary, t h e techniques and procedures f o r handling r a d i o a c t i v e samples.

The r e s u l t s of

t h e sample analyses w i l l be used i n conjunction with earlier r e s u l t s t o e s t a b l i s h b a s e l i n e s f o r t h e study of the e f f e c t s of power o p e r a t i o n .

4.2

PROCEIXJFBS

4.2.1 Shielding and Containment Surveys Surveys w i l l be made i n a l l a r e a s t h a t a r e a c c e s s i b l e during r e a c t o r operation; these surveys w i l l be c a r r i e d o u t a t a l l power l e v e l s including t h e h i g h e s t expected during any run. Except f o r t h e top plugs, t h e s h i e l d i n g around t h e r e a c t o r c e l l i s e s s e n t i a l l y t h a t which was i n s t a l l e d f o r t h e ART.

Calculations i n d i c a t e

t h a t before t h e WRE i s operated a t full power, a d d i t i o n a l s h i e l d i n g

w i l l be r e q u i r e d i n some areas.

Space was l e f t (on t h e o u t s i d e of t h e

s h i e l d ) f o r supplementary shielding, b u t none was i n s t a l l e d because d i f f ic u l t source and s h i e l d geometries made it impossible t o p r e d i c t a c c u r a t e l y t h e requirements.

Instead, r a d i a t i o n l e v e l s measured i n low-power

operation will be e x t r a p o l a t e d t o high power t o determine t h e amount of a d d i t i o n a l s h i e l d i n g a c t u a l l y required. J

4-3 One area where stacked block s h i e l d h g w i l l be added i s on the southwest of the r e a c t o r c e l l .

There the o r i g i m l shielding is t h i n n e r

i n the v i c i n i t y of the coolant piping penetrations and high dose r a t e s

are expected i n t h e coolant c e l l , the blower housq and outside the blower house.

Another area which w i l l be given' s p e c i a l a t t e n t i o n i s the north

e l e c t r i c s e r v i c e area.

There penetrations i n the wall of t h e south

e l e c t r i c s e r v i c e area will be moditored t o determine i f local s h i e l d i n g

is require&

(The oouth e l e c t r i c s e r v i c e area is shielded from the

r e a c t o r cell only by the c e l l annulua, and e n t r y will be prohibited during power operation. )

Surveys will also cover a l l o t h e r areas, f o r example:

t h e water

room, t h e special equipment room, the sump rom, t m n E m i t t e r room, s e r v i c e room, a d s e r v i c e tunnel. The f u e l system sampler-enricher will receive s p e c i a l a t t e n t i o n i n t h i s survey because it not only i s a shieldi n g problem but one of containment a s well. Shielding surveys will be made during t h e sampling operation and i n the manipulation of the sample a f t e r it has been withdrawn. The t o p of t h e r e a c t o r c e l l w i l l not be occupied during power operation, but r a d i a t i o n l e v e l s w i l l be measured t h e r e t o complete t h e survey of the s h i e l d and a l s o t o provide data which can be used f o r simple checks of the shielding c a l c u l a t i o n s . The primary accident containment, i . e . the Reactor and Drain-mnk Cells, will be hermetically sealed and maintained a t a pressure of 2 p s i below atmospheric (12.7 psire).

Containment i n t e g r i t y w i l l be monitored

by a system of reference vessels i n s t a l l e d i n the c e l l s t o measure pressure! changes, by monitoring the oxygen content of the containment atmosphere, and by determining the m o u n t of' exhaust from t h e vacuum Pumps Since t h e c e l l atmosphere will be kept at t r a t i o n (<

. l o w oxygen concen-

5%) by i n j e c t i o n of nitrogen a t a measured rite, it should

be p r a c t i c a b l e t o analyze f o r oxygen and relate the Inckease i n oxygen concentration t o c e l l inlea-.

If a continuous pump down of t h e c e l l

is necessary t o maintain t h e d e s i r e d negative pressure, then t h a t which is exhausted from the vacuum pumps may be measured and t h i s , when c o r r e c t e d

4-4 for nitrogen injection, w i l l represent the inleakage, The referencevessel technique for measuring containment leakage has been used quite extensively and is described in Om-CF-64-11-31.

All of the above

monitoring methods will be used until good confidence is established in our ability to continuously determine the cell leakage. The high bay of Building 7503 will be another containment barrier in case of an activity release. The building w i l l be kept at a negative pressure (- 0.1" â&#x201A;ŹI&) with reference to atmosphere.

The magnitude of

this negative pra~aurew i l l be measured in the high bay a6 w e l l as in individual cells and areas that are serviced by the building ventilation system. It should be amurea that air movement will be from the l e s s contminatcd to the more contaminated parts of the building.

4.2 2 Calibration of Nuclear-Power Instruments The neutron-aeneitive instruments which give signals proportional to nuclear power are the two wide-ra-nge counting channels, the two linear power channels and the three safety channels. The objective in the calibrations is to establish relationships between reactor power, instrument output, m d chmber location. Preliminary values will have been estublfshed prior to and during the zero power tests, but 8 s the power is raised to 1 Mw the greater precision with which reactor power can be measured w i l l permit more accurate determinations. The final relations will be determined later at high power, when hent balances w i l l be more accurate, but the calibrations at low power are necessary

to make the neutron instruments ueeful during the approach to full power. Calibration datu Will be obtained on the various iastmunents at

eeveral power levels up to 1000 kw. Below about 200 kw the most useful nuclear-power data w i l l probably be obtained from changes in the power to the electric heaters. Rates of change of system temperature will yield good information at powers above about 100 kw. System heat balances w i l l eive good msults above about 500 kw.

4.2.2.1 Pawtr -- Measlueaents Measurements of the change in instrument output as a function of power w i l l be made with the sensing elements in fixed locations. In

4-5 t h i s condition, t h e r e l a t i o n between the two parameters w i l l be essent i a l l y linear.

However, only the slopes of t h e r e l a t i o n s w i l l be ob-

t a i n e d becauses changes i n power, r a t h e r than absolute power, w i l l be measured, p a r t i c u l a r l y a t low l e v e l s .

Since t h e h s t r u m e n t s i g n a l s a r e

( i d e a l l y , a t l e a s t ) zero a t zero power, the curves can be t r a n s l a t e d

parallel t o themselves u n t i l they pass through the o r i g i n t o produce absolute calibrations.

Once these abaolute r e l a t i o n s h i p s have been

e s t a b l h h e d , t h e chambers can be l o c a t e d t o produce t h e required s i g n a l s t r e n g t h f o r a given power.

Changer i n Heater Power -+?he

energy input t o any h e a t e r o r group

of h e a t e r s can be determined from t h e c u r r e n t flow and t h e known res i s t a n c e of t h e h e a t e r elements.

If all o t h e r conditions are held

constant, any decrease i n heater power input must be accompanied by an equivalent increase i n nuclear power t o maintain steady tempemtures. Thus, t h e change i n heater input i s a d i r e c t measure of t h e change i n nuclear power.

Various amounts of e l e c t r i c heat, up t o about 200 kw,

w i l l be shut o f f t o obtain d a t a ,

(The l i m i t of 200 kw i s imposed on

t h i s method by the f a c t t h a t t h i s i s t h e normal h e a t e r requirement f o r s t e a d y - s t a t e operation a t zero power. ) Measurements involving only changes i n h e a t e r power r e q u i r e t h a t the system temperature remain constant with time.

If t h i s i s not the

case, c o r r e c t i o n s based on the rate of change of temperature and t h e system heat capacity w i l l be applied.

The d i r e c t correspondence between

changes i n heater power and nuclear power i s v a l i d only i f the h e a t l o s s e s from t h e c i r c u l a t i n g loops are independent of the h e a t e r s t a t u s ,

This independence i s expected t o be an adequate approximation f o r t h e early calibratione. Changes i n System Temperature -If

the heat removal from (or a d d i t i o n

t o ) t h e c i r c u l a t i n g loops remains constant i n time, any v a r i a t i o n i n t h e

rate of change df system temperature i s related t o a change i n nuclear power through t h e heat capacity of the c i r c u l a t i n g systems.

A series of

a r b i t r a r y changes i n nuclear power w i l l be made and t h e rates of change of system temperature will be observed t o dbtetin power c a l i b r a t i o n data. S i g n i f i c a n t v a r i a t i o n s i n the rate of change of temperature will r e s u l t

4-6 from power changes of 100 kw o r more.

These d a t a w i l l be used i n con-

j m c t i o n with t h e o t h e r measurements t o e s t a b l i s h t h e instrument c a l i b r a tions.

It i s a i t i c i p a t e d t h a t adequate data w i l l be obtained with no

more than 20째F change i n system temperature so t h a t t h e system h e a t l o s s e s w i l l n o t change s i g n i f i c a n t l y . Zeat Balances - Heat balances w i l l be c a l c u l a t e d a t a l l power l e v e l s (including zero power) t o determine a b s o l u t e powers f o r comparison with o t h e r measurements.

These c a l c u l a t i o n s w i l l give t h e a b s o l u t e nuclear

power when t h e system i s a t steady s t a t e .

Eiowever, s i n c e any h e a t

balance contains some e r r o r s which a r e n o t power dependent, t h e accuracy of t h i s method of power measurement w i l l improve w i t h increasing power. It i s expected t h a t t h e accilracy of t h e h e a t balance w i l l become comparable t o t h a t of t h e o t h e r methods of power measurement a t 0.5 t o 1 M w . 4.2.2.2

_Poai4i~n-Correla4i~n~

Since t h e s a f e t y chambers and t h e linear-power chambers w i l l remain i n f i x e d p o s i t i o n s during normal operation, it w i l l be necessary only t o l c c a t e t h e p o s i t i o n f o r each chamber t h a t gives t h e d e s i r e d r a t i o of output c u r r e n t t o nuclear power.

This i s t h e product of t h e r a t i o of

t h e chamber c u r r e n t t o neutron f l u x and t h e r a t i o of neutron flux t o c u c l e a r power.

The l a t t e r r a t i o i s a f u n c t i o n of p o s i t i o n and i s

p r a c t i c a l l y c o n s t a n t a t any p o s i t i o n .

On t h e o t h e r hand, t h e c u r r e n t / f l u x

r a t i o w i l l probably not be l i n e a r over t h e e n t i r e range of f l u x e s t o be encountered i n r e a c t o r operation.

Therefore, t h e s e chambers w i l l be

p o s i t i o n e d t o give maximum f i d e l i t y i n t h e normal power range, 1 t o 10 Mw. Measurements w i l l be nade

determine t h e e x t e n t of any d e v i a t i o n s from

l i n e a r i t y a t lower powers. The p r i n c i p l e of Operation of t h e wide-range counting channels derives from t h e approximately exponential decrease i n neutron f l u x along t h e instrument s h a f t .

Because t h e flux/power r a t i o does n o t decrease

p e r f e c t l y exponentially, an e l e c t r o n i c f u n c t i o n generator i s included i n each wide-range collnting channel t o produce a f u n c t i o n of chamber pos i t i o n t h a t i s l i n e a r l y r e l a t e d t o t h e log of t h e f l u x .

The i n i t i a l

s e t t i n g s of parameters i n t h e function generators w i l l be based on calcul a t i o n s , b u t a d d i t i o n a l adjustments w i l l be r e q u i r e d a f t e r t h e actual.

4-7 relations between flux and chamber position in the reactor installation have been determined. These relations will be determined at constant power by measuring count rates on each of the fission chambers as functions of chamber position. Two or more power levels differing by about three orders of magnitude may be required to cover the entire range of travel of the fission chambers. Since the fission chambers will be moved during normal operation, any flux perturbations (which may be caused by other chambers) through which the fission chambers must move must also be compensated for by the function generators. If the other chambers produce significant effects along the paths of the fission chambers, the function generators will be readjusted as necessary each time the other chambers are moved.

this same connection efforts will be made to identify any effects on other chamber signals as the fission chambers move past them.

4.2.2.3 Qtker :orrelgt&ogIt is not anticipated that conditions in the reactor, such as control-rod configuration or system temperature within the normal operating range, will significantly affect the relations between nuclear power and instrument signal. However, the data will be analyzed for evidence of any relations that may exist. The degree of compensation of the compensated ion chambers in the linear power channels can be adjusted if necessary. The data taken when t h e power is lowered and then r a i s e d (changing t h e r a t i o of gammas

to neutrons) will be analyzed to determine the need for such adjustments.

4.2.3 Power Coefficient of Reactivity If the reactor outlet temperature is held constant as the power is raised, the temperature distributions in the core result in effective,

or nuclear-average, temperatures in both the fuel and graphite which differ from the isothermal temperature of the zero-power system. The net reactivity effect of these changes in temperature is such that the control rods must be withdrawn slightly as the power is raised in order to maintain the desired outlet temperature. This reactivity effect is expected to be approximately linear with power level and will be described in system analyses in terms of a power coefficient of reactivity.

4-8 The most p r e c i s e measurements of the power c o e f f i c i e n t of react i v i t y will be made later i n t h e program when r a p i d power changes of s e v e r a l megawatts can be imposed on the system.

A t 1 Mw, t h e e f f e c t of

t h e power c o e f f i c i e n t of r e a c t i v i t y i s expected t o approach t h e lower

limit of d e t e c t i o n c a p a b i l i t y , so some preliminary measurements w i l l be made.

The c a l c u l a t e d power c o e f f i c i e n t f o r constant o u t l e t tempera-

($ 8k/k$w and t h e maximum d i f f e r e n t i a l worth of a s i n g l e c o n t r o l rod i s 0.08 ($ Sk/kfin., implying a change i n c r i t i c a l rod

t u r e i s -0.006

p o s i t i o n of o n l y about 0 . 1 i n . between zero power and 1 Mw.

Therefore,

measurements of t h i s parameter at 1 Mw w i l l be q u i t e crude, but wide deviations from t h e expected value should be d e t e c t a b l e . The achievement of s t e a d y - s t a t e temperatures is much more r a p i d

than o t h e r e f f e c t s of power operation (such as buildup of xenon and o t h e r f i s s i o n products o r f u e l burnup).

There the power c o e f f i c i e n t

can be determined from short-term changes i n c r i t i c a l control-rod posit i o n a s s o c i a t e d with changes i n power.

These changes w i l l be converted

t o r e a c t i v i t y with t h e a i d of control-rod c a l i b r a t i o n d a t a .

4.2.4

Xenon Poisoning The Xenon-135 poisoning effect i s of p a r t i c u l a r i n t e r e s t i n t h i s

r e a c t o r because of the presence of the unclad g r a p h i t e moderator.

Infor-

mation 2s required about t h e d i s t r i b u t i o n of ls5Xe i n t h e primary system a s w e l l as the t o t a l poisoning; p a r t of t h e xenon t h a t c o n t r i b u t e s t o t h e poisoning w i l l be c i r c u l a t i n g with t h e f u e l salt, while t h e remainder

i s absorbed i n the g r a p h i t e .

The xenon concentration i n t h e f u e l s a l t

depends s t r o n g l y on t h e e f f i c i e n c y of t h e s t r i p p i n g mechanism i n the pump bowl.

This, i n turn, i s influenced by c i r c u l a t i n g gas bubbles i n

t h e f u e l system and t h e level of t h e s a l t i n t h e pump bowl.

The xenon

concentration i n t h e g r a p h i t e depends on t h e mass-transfer c o e f f i c i e n t f o r xenon between the f u e l s a l t and the graphite, t h e concentration i n t h e c i r c u l a t i n g salt, and t h e d i f f u s i o n of xenon through g r a p h i t e . A s described i n s e c t i o n 2.3.1.3 (Krypton S t r i p p i n g ) , experiments

were performed t o measure t h e s t r i p p i n g e f f i c i e n c y i n t h e pump bowl and t h e mass t r a n s f e r C o e f f i c i e n t f o r gas t r a n s p o r t from t h e g r a p h i t e t o the c i r c u l a t i n g s a l t using "Kr,

These r e s u l t s were used t o e s t i m a t e the

4- 9 behavior of xenon i n the r e a c t o r system; i.e. the s t r i p p i n g of xenon i n t h e pump bowl and t h e mass t r a n s f e r of t h i s gas from the s a l t t o t h e graphite.

On t h i s b a s i s , the xenon poisoning i s expected t o be of t h e

order of 0.005 t o 0.05

( 3 Sk/k)/Mw

(compared t o

0.2

($ Sk/k)/Mw f o r a

s t a t i o n a r y - f u e l r e a c t o r with the same core composition).

This means

t h a t during t h e low-power t e s t s , t h e r e a c t i v i t y e f f e c t s of xenon may be

t o o small f o r s i g n i f i c a n t measurement.

Nevertheless, t h e r e a c t i v i t y

e f f e c t s of changes i n power w i l l be analyzed f o r evidence of xenon poisoning. I n a d d i t i o n t o the d i r e c t observation of r e a c t i v i t y e f f e c t s , t h e determination of t h e 136Xe

- 134Xe

r a t i o i n t h e f u e l system offgas gives

information on t h e poisoning by 135Xe.

The provisions and t h e tech-

niques f o r sampling t h e offgas and analyzing f o r t h e xenon i s o t o p i c r a t i o s w i l l f i r s t be p u t t o use during t h e low-power operation.

4.2.5

On-Line Analysis of Operation

An important f u n c t i o n of t h e on-line computer w i l l be the reduction and a n a l y s i s , on a real-time o r c u r r a n t basis, of r e a c t o r d a t a as they a r e accumulated from t h e operating system.

These operations w i l l be

performed i n a d d i t i o n to, and concurrent w i t h , t h e r o u t i n e signal-monitoring and d a t a - a c q u i s i t i o n functions of the computer. The operation of t h e computer and t h e mechanical performance of t h e various computations i n t h e programs w i l l have been checked o u t

during earlier phases of t h e program.

(See 2.3.12.2).

However, many of

the programs are designed t o e v a l u a t e t h e performance of t h e r e a c t o r

system during power operation.

The mathematical treatments and t h e

values of parameters i n t h e i n i t i a l versions of t h e s e programs a r e based p a r t l y on t h e o r e t i c a l considerations and p a r t l y on empirical r e s u l t s of

e a r l i e r operations.

Therefore, the adequacy w i t h which these c a l c u l a -

t i o n s describe the operating r e a c t o r can be determined only under operating conditions.

It i s expected t h a t operation a t power l e v e l s

approaching 1 Mw will provide t h e f i r s t opportunity t o check o u t t h e c a l c u l a t i o n s t h a t w i l l be used l a t e r t o monitor r e a c t o r behavior.

(It i s q u i t e l i k e l y t h a t full-power operation f o r some t i m e w i l l be r e q u i r e d

before the f f n a l versions of some programs are e s t a b l i s h e d . )

4-10 4.2.5.1 Regc+-ixiLy-@lgceThe ultimate function of t h e r e a c t i v i t y balance i s t o r e v e a l any deviations or anomalies i n t h e r e a c t i v i t y behavior of t h e c r i t i c a l reactor.

Such balances w i l l b e c a l c u l a t e d every 5 minutes (and on demand)

and excessive deviations will be c a l l e d t o t h e a t t e n t i o n of t h e o p e r a t x s . Under normal circumstances, t h e results of t h e r e a c t i v i t y balance are p r i n t e d out once an hour and a l l other results are s t o r e d on magnetic tape. The r e a c t i v i t y balance sums all t h e r e a c t i v i t y changes, both p o s i t i v e and negative, from a reference condition and compares t h e r e s u l t t o t h e expected result, namely zero.

The reference condition f o r t h e

MSRE i s t h e j u s t - c r i t i c a l , clean, zero-power r e a c t o r a t l2OO0F w i t 5 a l l

c o n t r o l rods f u l l y withdrawn.

With t h i s b a s i s , t h e oriiy p o s i t i v e r e 0

a c t i v i t y term (provided t h e r e a c t o r o u t l e t temperature i s 1200 F o r g r e a t e r ) i s t h a t due t o excess uranium concectration.

The program computes t h e

sum of a l l uranium a d d i t i o n s a f t e r t h e achievement o f i n i t i a l c r i t i c a l i t y and c o r r e c t s t h i s f o r burnup t o o b t a i n t h e c u r r e n t concentration.

The

following negative c o n t r i b u t i o n s t o t h e r e a c t i v i t y balance are considered:

power e f f e c t , computed from power l e v e l and t h e empirically determined power c o e f f i c i e n t of r e a c t i v i t y ,

temperature effect, computed from t h e r e a c t o r o u t l e t temperature and t h e isothermal temperature c o e f f i c i e n t of r e a c t i v i t y ,

control-rod poisoning, computed from rod-position data and empirical c a l i b r a t ions

xenon poisoning, computed from t h e power h i s t o r y of t h e reactor,

samarium poisoning, computed from t h e power h i s t o r y , and

poisoning dJe t o o t h e r f i s s i o n products, computed from t h e power history. The 0d-y parameters t h a t w i l l be known with any degree of c e r t a i n t y

a t t h e s t a r t of low-power operation are t h e temperature c o e f f i c i e n t and

t h e control-rod worth.

A l l t h e o t h e r parameters and, i n t h e cases of

Xe and Sm, Vne models f o r describing t r a m i e n t behavior must be v e r i f i e d

4- 11 o r a d j u s t e d on t h e b a s i s of operating experience.

If t h e r e i s no o t h e r

evidence of anomalous behavior a t powers up t o 1 Mw, t h e r e a c t i v i t y balance w i l l be a d j u s t e d t o give zero n e t r e a c t i v i t y f o r a l l conditions. Since most of t h e r e a c t i v i t y e f f e c t s w i l l be small a t 1 Mw, t h e a d j u s t ments made during t h i s phase of operation w i l l c e r t a i n l y have t o be r e f i n e d when higher powers a r e achieved. 4.2.5.2

gegt-Blgnse-

A h e a t balance w i l l be c a l c u l a t e d and p r i n t e d o u t by t h e computer

every 4 hours (and on demand).

It i s expected t h a t heat-balance calcu-

l a t i o n s a t zero power w i l l have r e s u l t e d i n a good value f o r unmeasurable h e a t - l o s s terms (see 2.3.22.4).

This term w i l l then be used i n h e a t

balances a t power t o evaluate the n e t nuclear power.

The heat-balance

r e s u l t w i l l be compared with manual c a l c u l a t i o n s and o t h e r power b r a t i o n s t o demonstrate i t s adequacy,

Cali-

Term-by-term comparisons w i l l

permit modification of t h e computer program i n any a r e a s i n which it i s inadequate.

4 2.5.3 a

ga&t-IGvgnLory-

Inventories of f u e l , flush, and coolant s a l t s w i l l be c a l c u l a t e d every 8 hours (and on demand).

The purpose of t h e s e c a l c u l a t i o n s i s t o

r e v e a l any changes i n inventory which may i n d i c a t e s a l t l o s s e s .

There-

fore, i t i s e s s e n t i a l t h a t the c a l c u l a t i o n s properly account for t h e changes i n bulk-average temperature i n t h e non-isothermal loops when t h e r e a c t o r i s a t power.

The adequacy of these c a l c u l a t i o n s w i l l be

checked under no-loss conditions (which can be v e r i f i e d by r e t u r n i n g t o the isothermal s t a t e ) and modified t o give t h e r e q u i r e d r e s u l t s . 4.2.5.4

o t h e r QnlLing ~ a ~ c u l ~ t i o ~ s

The computer w i l l also perform a number of o t h e r c a l c u l a t i o n s whose r e s u l t s may depend on t h e r e a c t o r power l e v e l . 1.

These include:

t a b u l a t i o n of t h e number of power-induced thermal cycles on t h e f u e l pump tank,

t h e temperature d i f f e r e n c e between t h e f u e l i n l e t and t h e lower head of t h e r e a c t o r vessel,

t h e temperature d i f f e r e n c e between t h e f u e l i n l e t and t h e coresupport flange,

4-12

4. 5.

c e l l - a i r average temperatures, and nuclear average t e m p e r a t x e s of t n e f u e l and g r a p h i t e .

AL1 t h e s e c a l c u l a t i o n s will be exambed a t low power, f i r s t t a determine t h e adequacy with which they r e f l e c t a c t u a l occurrecces, and second t o determine t h e i r p o t e n t i a l value i n revealing operatLng acomalies.

4= 2 5.5

Zrgcgssing-OLd -I)ata -

I n a d d i t i o n t o t h e reduction of c u r r e n t data i n r e a l t i m e , t h e computer has t h e c a p a b i l i t y f o r r e t r i e v i n g and processing previously recorded information.

This work, including preparation of t h e necessary

programs, can be carried out while t h e computer i s on-li3e without i r ; t e r f e r i n g with t h e on-line functions.

(me

poss5bility also exists

f o r adding t o t h e on-line functions of t h e machine. )

Since t h e nature

of t h e data processing t h a t w i l l be required depends on t h e operating experience with t h e r e a c t o r , it i s not p o s s i b l e t o s p e c i f y t h e calcul a t i o n s t h a t w i l l be performed.

I n cases where advance s p e c i f i c a t i o n

w a s possible, t h e c a l c u l a t i o n s were included i n t h e on-line func%ions.

4.2.6

Establishment of Baseline f o r Chemical Analyses During t h e low-power operation t h e program of sampling and a2alyzing

t h e f u e l salt, s t a r t e d during t h e zero-power experiments, w i l l be extended and broadened.

A t a l l power l e v e l s , information concerning t h e

i n t r i n s i c s t a b i l i t y of t h e f u e l as w e l l as t h a t v i s - a - v i s

INOR-8,

graphite, and f i s s i o n products, w i l l be furnished by t h e r e s u l t s of chemical a n d y s e s .

One important goal, therefore, w i l l be t o prepare f o r

t h e study of power e f f e c t s by e s t a b l i s h i n g with maximm confidence t h e concentrations of those c o n s t i t u e n t s which w i l l be of i x t e r e s t during l a t e r operation a t higher power. A f u e l s a l t sample w i l l be taken r o u t i n e l y once a day f o r a n a l y s i s

i n t h e High Radiation Level Analytical F a c i l i t y (HRLAF).

Analyses w i l l

include t h e primary s a l t constituents, corrosion products, o-yygen, and t h e reducing power of t h e s a l t . Growth of f i s s i o n products i n t J t h e f u e l during r e a c t o r operation w i l l be followed by measuring t h e c h a r a c t e r i s t i c a c t i v i t y s p e c t r a of s a l t

specimens.

This type of a n a l y s i s w i l l be i x t i t u t e d during t h e

4-13 low-power operation and the r e s u l t s w i l l be r e l a t e d t o c a l c u l a t i o n s of burnup and f i s s i o n product growth. The operation a t l o w power will also be used t o f u r t h e r evaluate and prove a l l of t h e o t h e r techniques and procedures involved i n hand-

ling r a d i o a c t i v e samples,

4.2.7

Intermediate Dynamics Studies Dynamic t e s t s will be made a t each power l e v e l during low power

These tests will use control-rod perturbations t o give react i v i t y pulse6 and pseudo-random binary r e a c t i v i t y inputs. The procedure will be the same as f o r t h e zero-power tests discussed i n 3.2.3. testing,

The observed t r a n s i e n t response will be compred with t h e calculated t r a n s i e n t response.

Methods a r e being developed t o automatically

a d j u s t t h e p m e t e r s i n the t h e o r e t i c a l model t o agree with the experimental results.

The t r a n s i e n t response r e s u l t s w i l l be Fourier analyzed t o give the frequency response.

The frequency response a s &ll

as the t r a n s i e n t

response w i l l be used i n the automatic parameter adjustment r o u t i n e . The e f f e c t of r e a c t i v i t y feedback due t o temperature changes w i l l begin t o appear a t these low power l e v e l s .

Analysis of the frequency response

&ta will give some i n d i c a t i o n of the v a l i d i t y of the feedback model used i n t h e t h e o r e t i c a l c a l c u l a t i o n s . The inherent f l u c t u a t i o n s i n the f l u x l e v e l w i l l be analyzed and t h e s p e c t r a l d e n s i t y of these f l u c t u a t i o n s w i l l be determined.

The s p e c t r a l

d e n s i t y gives t h e product of t h e square of t h e system t r a n s f e r function and t h e s p e c t r a l d e n s i t y of the i n p u t ,

Since t h e system t r a n s f e r function

w i l l be known from the pulse tests and pseudo-random binary input t e s t s ,

it may be possible t o i s o l a t e the s p e c t r a l density of the input.

This

w i l l help i n determining the cause of the f l u c t u a t i o n s .

These tests w i l l i n d i c a t e the s t a b i l i t y performance of t h e system a t a p a r t i c o r power l e v e l .

Also, the trends i n t h e s t a b i l i t y performance

with power l e v e l w i l l be determined by comparison with previous r e s u l t s . These r e s u l t s , along with t h e o r e t i c a l r e s u l t s using a model updated w i t h

latest Information, w i l l be used t o p r e d i c t system s t a b i l i t y a t t h e next power l e v e l before the power i s changed.

SECTION 5 FZACTOR CAPABILITY IWESTIGATIONS APPRGACH TO FULL POWER 5.1 OBJECTI'dES

This phase of the test program is the logical extension of the operation at low powers. The primary objective is to raise the power level, in steps, to the design power of 10 Mw. The principal difference between the operation in this phase and earlier operations is in the mode of power control. The load on the reactor will be established by adjusting the rate of heat extraction at the radiator while both the nuclear power and the primary-system temperature are controlled automatically. Although the primary objective is to increase the power, the objective of each of the individual tests is to determine whether or not there is any aspect of the operation that might restrict the attainment of the primary objective. Therefore, experiments will be performed at

each power step to establish the mechanical, thermal, nuclear, and chemical performance of the system. This performance will be analyzed in the light of theoretical and design predictions, observations at lower powers, and extrapolations of earlier results. Any unexpected or anomalous behavior that may be observed will be resolved before the next power increase. If any limitations are approached that can be relieved (for example, by improving shielding, cooling, or heating), the necessary

corrective measures will be taken at the same time. In addition to permitting evaluation of the reactor system, operation at intermediate powers will permit the refinement of calculational models, techniques, and parameters to be used in predicting the behavior at successively higher powers. Since a number of factors, and hence the accuracy with which they can be evaluated, depend on power, time at power, or just time, it is expected that improvements in the ability to evaluate the system will continue throughout the operation. The anticipated steps in the approach to 10 Mw are: 1.5, 3.0, 5.0, W

and 7.5 Mw.

Before the power is raised above 5 Mw, the reactor will be

5-2

operated. a t t h a t power long emugh t c discern any short-term e f f e c t s on the f u e l s a l t .

This w i l l r e q u i r e abcut 1 5 days from t h e Seginning of

5 Mw operation u n t i l the power i s rLised t o 7.5 Mw. A t 1.5, 3.0, and 7.5 Mw about 5 days w i l l elapse betweer power i-ilcreas?s. These tfmes are, of course, based on the assimption of no d i f f i c 7 J l t i e s or anomalous If such appear, t h e schedule w i l l be re-

behavior t o be i n v e s t i g a t e d . vised as necessary.

PROCED3RES

5.2.1 Performance of Control Systems The r e a c t o r power l e v e l , above 1 Mw, Ls determined by t h e heat re-

moval r a t e a t t h e r a d i a t o r -&icn i s s e t by a combir,aticn cf the radiator-door and bypass-damper p o s i t i o n s , and the mmber of' main blowers operating.

The automatic temperature-control servo then a d j u s t s t h e

r e a c t o r power t o meet t h i s load demand while rnaintaining t h e r e a c t o r o u t l e t temperature constant a t some p r e s e l e c t e d value. The c o n t r o l l e r has been t e s t e d and t h e required adjustmer,ts have been made using an analog ccmputer.

The t e s t program, therefore, con-

s i s t s of insuring t h a t t h e c o a t r o l system w i l l maLntain t h e proper cont r o l of the r e a c t o r power and o u t l e t temperature a t various power l e v e l s , and t h a t the c o n t r o l system has adequate response t o cover t h e ?orma1 t r a n s i e n t s which may occur. With the system operating cn ternplirakire servfi snd- with t h e temperat u r e s e t p o i n t a t 12OO0F, t h e system w i l l be cperated a t a cozstant l o a d demard r t t h e r a d i a t o r f o r a period of t i m e s u f f i c i e n t t o determir,e i f t h e o u t l e t temperature remains constant, o r i f t h e r e i s a lor,g-term temperature d r i f t .

The system w i l l a l s o be cbserved f o r outlet-temperature

or f l u x cycling and f o r excessive control-rod "hunting".

The steady-

state operating t e s t s w i l l be conducted a t each power l e v e l ,

StEady-

state operation w i l l a l s o be reviewed t o determine i f t h e small changes

i n r a d i a t o r l o a d demand r e s u l t i i g from changes i n ambient a i r temperature can be detected by changes i n the neutron f l u x l e v e l .

5-3 A s e r i e s of tests w i l l a l s o be run a t t h e same power l e v e l s t o

determine t h e c o n t r o l system performance under t r a n s i e n t conditions. The c o n t r o l a c t i o n and t h e r e a c t o r system response w i l l be observed during t r a n s i e n t s introduced i n t h e following manner t o determine i f t h e t r a n s i e n t s a r e s a t i s f a c t o r i l y c o n t r o l l e d and t o determine i f t h e "computedflux-demand" l i m i t a t i o n of 1/2 t o 11 Mw i s adequate.

The temperature s e t

p o i n t w i l l be changed from 1200 t o 1225째F a t t h e normal motor-driven r a t e of 5째F p e r minute and held t h e r e u n t i l t h e r e a c t o r system reaches steady

state.

The s e t p o i n t w i l l then be returned t o 1200째F. A r a p i d load-

demand change of about 2 Mw w i l l be made a t the r a d i a t o r by changing door p o s i t i o n or by changing t h e bypass-damper p o s i t i o n .

With t h e r e -

a c t o r operating a t s t e a d y - s t a t e conditions under manual control, t h e system w i l l be switched t o temperature servo with both a p o s i t i v e and a negative 5'F d i f f e r e n t i a l between t h e r e a c t o r o u t l e t temperature and t h e s e t - p o i n t temperature.

The t e s t w i l l then be repeated using a 25째F

temperature d i f f e r e n t i a l . *

Adjustments w i l l be made on t h e c o n t r o l l e r t o c o r r e c t any areas of poor performance which a r e found by t h e above t e s t s , and t h e t e s t program w i l l be repeated.

If u n s a t i s f a c t o r y operation i s found a t c e r t a i n power l e v e l s which cannot be c o r r e c t e d by adjustment of t h e c o n t r o l l e r , f u r t h e r t e s t s w i l l be performed to define the range of s a t i s f a c t o r y performance.

5.2.2

Shielding and Containment Adequacy The s h i e l d i n g surveys t h a t weye c a r r i e d o u t a t low power (4.2.2)

w i l l be continued a t a l l power l e v e l s up through 10 Mw.

Farticular

a t t e n t i o n w i l l be given t o t h e two areas mentioned i n 4.2.1; t h e north e l e c t r i c - s e r v i c e area and t h e south-west s i d e of t h e f a c i l i t y b u i l d i n g . Continued i n t e n s e s u r v e i l l i e n c e w i l l . be c a r r i e d o u t f o r t h e purpose of l o c a t i n g p o i n t s a t which dose rates are higher than expected. A s r e a c t o r power i s increased t h e r a d i a t i o n source i s increased p r o p o r t i o n a l l y because of t h e f i s s i o n process.

In addition, operation

f o r long periods of time w i l l r e s u l t i n an increase i n the r a d i a t i o n source because of fission-product buildup i n the s a l t .

Since both of

these f a c t o r s a f f e c t the dose r a t e outside of toe b i o l o g i c a l shield, it may be d i f f i c u l t t o e x t r a p c l a t e dose-rate m?%:iirements taken with clean s a l t a t low power (<1 Mw) t o the f i s s i o ~ - p r o d ~ c t - c o n t m i ~ ~s a t el td a t

high power.

Therefore, c a r e f u l dose-rate measwements w i l l be made i n

a l l areas t o v e r i f y the extrapolations t h a t were made from t h e low-power

measurements.

A s t h e r e a c t o r operates, aczumiilating fLssi.cn products,

the charcoal beds w i l l become a progressively g r e a t e r r a d i a t i o n source which w i l l produce measurable d m e rates o r l y af'ter t h e r e a c t o r has operated for some period of t i m e .

Continued monitoring of those beds

w i l l be c a r r i e d out i n t h e approach t o f u l l power.

For t h e reasons o u t l i n e d i n t h e previous paragraphs, t h e samplere n r i c h e r w i l l come under c l o s e s c r u t i n y as power i s increased.

3ose

rates during t h e sampling operation may increase v i t h t h e snd power l e v e l ; t h i s w i l l be monitored. Continued monitoring of the containmezt in-leakage and of t h e building v e n t i l a t i o n system w i l l be c a r r i e d on

8':

s i l t l i n e d i n 4.2.1.

5.2.3 C a l i b r a t i o n of Power Instruments C a l i b r a t i o n measurements or? a l l the nuclear power instruments w i l l be continued throughout t h e approach t o f d l power.

The purpose of

these measurements i s t o determine t h e f i n a l adjustments i n chamber p o s i t i o n required t o produce the optimum c o r r e l a t i o n betweerl indicat,ed pcwer and a c t u a l t'nermal power.

Measlx-ements w i l l a i s o be made t o

demonstrate t h e adequacy of t h e wide-range ccu-rtiag channels over t h e e n t i r e power range. The data t o be obtalned is e s s e n t i a l l y t h e same as t h a t c a t i i c e d

i n 4.2*2. Zowever, the exclusive c a l t b r s t i o c standard i n t h i ; p b s e cf t h e operation w i l l be the system h e a t b a l a w e . balances w i l l be c a r e f u l l y checked t c er:;ure

Tnerefore, t h e heat

t h a t no avoidable e r r o r s

are introduced, e i t h e r i n t h e d a t a o r the c a l c u l a t i c m . The l a r g e s t s i n g l e term i n t h e heat Palance i s t h e heat removal by t h e coolact s a l t . nuclear power

This term a c c o m t s f c r more than 95% cf t h e t c t a l

A s m 2 1 1 , s p e c i s l - p u r ~ o s e , acslog device i s i n s t a l l e d

t o contifiuously compute and record t h e c L o l a n t - s s l t h e a t removal from

5-5 t h e measured s a l t flow r a t e and temperature drop a t t h e r a d i a t o r . Operation a t powers above 1 Mw w i l l enable us t o check t h e output of t h i s device a g a i n s t t h e heat balance and t o a d j u s t i t s f i x e d parameters t o produce agreement between it and t h e standard.

Another check

on t h e heat removal a t t h e r a d i a t o r i s t h e heat absorbed by t h e a i r flowing through the r a d i a t o r enclosure.

Since t h e c o o l a n t - a i r s t a c k

w i l l be c a l i b r a t e d , t h e product of a i r flow and temperature r i s e (coupled w i t h t h e h e a t c a p a c i t y of the a i r ) w i l l be compared w i t h t h e o t h e r

calculations. 5.2.4

Xenon Poisoning The behavior of Xenon-ijj w i l l be s t u d i e d during t h e approach t o

f u l l power by observation of r e a c t i v i t y e f f e c t s and by i s o t o p i c a n a l y s i s of the xenon i n t h e o f f g a s . R e a c t i v i t y changes w i l l be observed a f t e r t h e power i s stepped up

or down between a few kilowatts and s e v e r a l megawatts.

The s t e a d y - s t a t e

change i n r e a c t i v i t y w i l l be corrected f o r the temperature e f f e c t s (which occur more r a p i d l y than t h e xenon e f f e c t s ) t o g e t t h e n e t poisoning e f f e c t of t h e '"Xe.

The xenon poisoning t r a n s i e n t s w i l l be analyzed

t o determine t h e b e s t mathematical r e p r e s e n t a t i o n .

If t h i s is a signifi-

c a n t improvement over t h e xenon computation programmed i n t h e computer, the computer program w i l l be modified. The r a t i o of 136Xe t o 13*Xe w i l l be determined i n samples of t h e offgas.

Comparison with t h e f i s s i o n y i e l d s of these isotopes w i l l show

the increase i n 136Xe due t o captures i n 13'Xe.

Steady-state information

w i l l be compared w i t h t h e n e t r e a c t i v i t y e f f e c t observed independently.

Offgas samples during t r a n s i e n t s may give information on t r a n s f e r between t h e s a l t and g r a p h i t e .

Ratios of radioisotopes of xenon (and of krypton)

w i l l give a measure of t h e "age" of t h e gases or how quickly they a r e

removed from t h e r e a c t o r . 5.2.5

On-Line Analysis of Operation The on-line, computerized a n a l y s i s of t h e r e a c t o r operation t h a t was

s t a r t e d a t low power (see Sec. 4.2.5)

will be continued throughout t h i s

and a l l subsequent phases of t h e program.

The p r i n c i p a l purpose during

5-6 the early part of the approach to full power is the refinement of the calculations and the establishment, if possible, of their final forms. However, since the possibility of anomalous or undesired behavior of the reactor exists at all power levels, any differences between observed reactivity behavior and that predicted by the computer program will be examined with great care. If such disagreements occur and can definitely be attributed to inadequacies in the calculations of known reactivity factors, the calculations will be modified or compensated for before the next power increase. If, on the other hand, the evidence is inconclusive or points to anomalous behavior of the reactor system itself, the experi-

mental operation will aim at resolving the anomaly before the power is raised further.

5.2.6 Thermal Effects of Power Operation As the reactor power is increased from a low level to the design power of 10 Mw, significant changes in temperature will occur throughout the system. These temperature changes should follow the predictable changes in fluid temperature which result from heat generation in the fuel in the reactor vessel, heat transfer to the coolant system in the heat exchanger, and heat removal from the coolant salt in the radiator. However, if abnormal conditions develop, certain fuel-system temperatures, especially in the reactor vessel, may deviate from the expected trends. The increase in power from 1 Mw to 10 Mw will be made in several increments, and a complete set of thermocouple readings will be taken at each power level after the system has reached steady-state conditions. The temperatures will be compared with the values from the previous power level, and the change in temperature w i l l be compared with the expected change. Particular attention will be paid to areas where solids might possibly accumulate (if they form).

The core-support ring and the lower

head of the reactor vessel are two such regions; these have sufficient thermocouples attached to the walls so that overheating caused by solids deposition should be detectable. If any excessively high temperatures are encountered or if any trends are observed which would lead to

5 -7 excessively high temperatures a t f u l l power, t h e r e a c t o r power l e v e l w i l l be h e l d a t / o r below t h a t p a r t i c u l a r power u n t i l a more d e t a i l e d i n v e s t i g a t i o n of t h e s p e c i f i c problem can be completed. One of t h e areas most s e n s i t i v e t o t h e normal thermal e f f e c t s of

power operation i s t h e fuel-pump tank.

Detailed temperature-distribution

and thermal-stress c a l c u l a t i o n s have been completed f o r zero and f u l l power operation and a cooling a i r flow has been s e l e c t e d t o maintain t h e thermal stress within acceptable l i m i t s .

The pump-tank temperatures

w i l l b e observed a t each power l e v e l , azzd adjustments w i l l be made on t h e

cooling-air flow rate as required. Capability and Performance of Heat Transfer Systems

5.2.7

It i s t h e purpose of t h i s program t o determine whether or not any h e a t removal system w i l l l i m i t t h e power l e v e l o r i n any other way curt a i l t h e success of t h i s experiment.

The primary h e a t exchanger ( f u e l

t o coolant) and t h e r a d i a t o r (coolant t o a i r ) a r e t h e most important h e a t t r a n s f e r systems i n t h e p l a n t .

The proper performance of t h e r e a c t o r

depends d i r e c t l y upon these two components.

Because of t h i s , c a r e f u l

evaluation of t h e i n i t i a l h e a t t r a n s f e r c a p a b i l i t y and long term p e r formance are planned.

Evaluation of some a u x i l i a r y systems i s a l s o

planned.

5.2.7.1

SLrngrX ge.t-Egc&asggx+-

Use of t h e on-line computer allows r a p i d accumulation of data from which t h e value f o r t h e o v e r a l l heat t r a n s f e r c o e f f i c i e n t can be calculated.

The c a l c u l a t i o n w i l l u t i l i z e a l a r g e number of thermocouple

readings on t h e f u e l and coolant piping a t s e v e r a l d i f f e r e n t power l e v e l s t o reduce t h e effects of i n d i v i d u a l thermocouple bias which would preverit meaningful c a l c u l a t i o n of heat t r a n s f e r c o e f f i c i e n t from a s i n g l e s e t of readings.

This program w i l l be continued throughout t h e operating

l i f e of t h e E R E .

The d a t a taken during t h e i n i t i a l approach t o power

w i l l be used t o c a l c u l a t e a value f o r t h e o v e r a l l c o e f f i c i e n t which w i l l

i n d i c a t e t h e performance of t h e h e a t exchanger a t t h e o u t s e t and w i l l provide b a s e - l i n e d a t a f o r t h e program discussed i n 6.2.4.

5-8 5 0 2 0 7 0 23

s Eaaiatgr-

Following the changes rin heat t r a m f e r c h a r a c t e r i s t i c s t h a t mfght occur i n the r a d i a t o r w i l l be mwe d i f f i c u l t than with the primary heat exchanger.

A t v a r i o ~ i spower c m d i t i o n s , the neat t r a n s f e r a r e a and the

a i r v e l o c i t y across the radiattsr w i l l chaige, maklng i t impractical t o

zompute the c v e r a l i heat t r a n s f e r c o e f f i c i e n t .

Since t h i s 9s true, a

value for t h e prod-Let of the overs11 heat t r a n s f e r c o e f f i c i e n t a r d the surface a r e a w i l l be used f o r a n a l y s i s .

This value w i l l be computed a t

v a r h u s times with r a d i a t o r door positfon (which gcverns t h e heat t r a n s f e r a r e a ) and a i r v e l o c i t y across the tubes s p e c i f i e d .

It i s expected t h a t

t h e most meaningful data w i i l be taken a t / o r near maximum power because under these conditions t h e o v e r a l l heat t r a n s f e r c o e f f i c i e n t can be calcalated.

The on-line compuzer w i l l be used i n the a n a l y s t s of the

r a d i a t o r data. Au&i&igry: Coglgrg

5.2.7.3

Cooling for i n - c e l l components i s provided by t h r e e a u x i l i a r y cooling systems. 1.

The componerlt-cooling-air system provides cooling f o r t h e f x 1 pump

bowl and for f r e e z e valves i n the r e a c t c r and d r a i n tank c e l l s . 2.

The c e l l a i r coolers w i l l 'oe expected t c maintain c e l l amlsient

temperature below 150째F a t a l l power i e v e l s .

The t r e a t e d water cooler provides a heat s i n k for s e v e r a l i n - c e l l

components including the thermal shield, ce;i a i r c o d e r s , ccmponentcooiing-hir cooler, and c t h e r smaller i t e n s . I n l e t and oictlet temperat;res

arid flow r a t e s t o +,he ccf;iers w i d be

measured azd t h i s together v i t k a value f o r the heat t r a n s f e r sdrfaze a r e a w i l l be used t o evapiate the c v e r a i i neat t r a n s f e r cuefficieKt.

It i s planned t o obtain data f o r i r , i t i a l evaldation of t h e performance of these coolers 5.2.8

t L

prsvide a bdsis f o r f u t u e s;rveillance.

Chemical E f f e c t s of' Power Operatio' %he evidence of the in-pi12 t e s t i r ~ gprograms iaditcates t h a t the

thermal a r d r s d i a t i o n environmert atter-dirg puver operation of the MSRE w i l l have

d e l e t e r i m s e f f w t on t,h? f-Jei s a l t o r the compatibilfty

of the s a l t , graphite, m d 3 1

-8.

Severtheless, the f z e l s a l t will

be sampled f r q m c t i y 1dii~5r-gthe apprmch to f u l l power and t h e a n a l y t i c a l

5 -9 r e s u l t s w i l l be s t u d i e d and tested s t a t i s t i c a l l y t o determine i f t'nere

are d i s c e r n i b l e e f f e c t s of power l e v e l o r i n t e g r a t e d power.

5.2.9

Dynamics Studies

The t e s t s made during low-power operation (see 4.2.7) t i n u e d throughout t h e approach t o f u l l power.

w i l l be con-

As i n t h e low-power tests,

these tests w i l l serve t o determine system s t a b i l i t y and t o f u r n i s h

information on system parameters and t h e v a l i d i t y of c a l c u l a t i o n a l methods. The power l e v e l during t h i s phase w i l l be high enough t h a t t h e

effect of power l e v e l on system temperatures, and thus r e a c t i v i t y , w i l l become important.

Analysis of t h e s e tests w i l l f u r n i s h an improved

c h a r a c t e r i z a t i o n of t h e feedback e f f e c t s i n t h e t h e o r e t i c a l model. The increased power l e v e l will a l s o make it p o s s i b l e t o introduce system p e r t u r b a t i o n s by load changes as well as by control-rod p o s i t i o n i n g . This will be accomplished by adjustment of p o s i t i o n of t h e r a d i a t o r doors and t h e observed temperature t r a n s i e n t s w i l l be compared with p r e d i c t i o n s . The procedure f o r automatic adjustment of appropriate system parameters t o cause agreement between t h e o r e t i c a l and experimental r e s u l t s will be used.

This can be used t o give d i r e c t information on t h e feedback t r a n s -

f e r function.

SECTION

SYSTEM CAPABILITY INVESTIGATIONS

- EXTENDED OPERATION

6.1 OEUECTIVES Once t h e o p e r a b i l i t y and s t a b i l i t y of t h e r e a c t o r system have been demonstrated a t f u l l power, t h e next l o g i c a l s t e p i s s u s t a i n e d operation a t high power l e v e l s .

The general o b j e c t i v e s of t h i s phase of t h e opera-

t i o n are t o demonstrate t h e d u r a b i l i t y of t h e r e a c t o r system and t o permit i n v e s t i g a t i o n of any e f f e c t s of long-term operation. Samples of t h e fuel and coolant salts w i l l be removed a t r e g u l a r intervals for detailed analysis.

These w i l l be used t o study t h e behavior

of t h e major c o n s t i t u e n t s of the salts as w e l l as the e f f e c t s of f i s s i o n products, corrosion products, and any o t h e r contaminants t h a t may be i n t r o duced.

Specimens of g r a p h i t e and

INOR-8 will

be removed from t h e core

p e r i o d i c a l l y t o provide f u r t h e r d a t a about t h e c o m p a t i b i l i t y of these m a t e r i a l s with t h e s a l t s during long-term i r r a d i a t i o n .

These specimens

w i l l also a i d i n p r o j e c t i n g t h e operating l i f e of t h e system. Many of the components i n use a t , t h e MSRE were developed s p e c i f i c a l l y f o r t h i s a p p l i c a t i o n and a r e similar to components t h a t would be used on l a r g e r molten-salt r e a c t o r s .

Therefore, component performance w i l l be

c a r e f u l l y monitored and evaluated t o provide reference d a t a f o r continuing development

An important a s p e c t of t h e long-term operation of t h e r e a c t o r system

i s t h e a b i l i t y t o perform maintenance on the equipment.

We expect t h a t

component f a i l u r e s w i l l occur and that remote maintenawe techniques w i l l be required t o r e p a i r o r replace the f a i l e d items.

Demonstration t h a t

remote r e p a i r s can be made without excessive expenditures of time and e f f o r t i s a necessary p a r t of t h e o v e r a l l f e a s i b i l i t y demonstration. The f u e l t o be used i n t h e i n i t i a l operation of t h e MSRE contains 23%

as t h e f i s s i o n a b l e material with some d i l u e n t

238u.

Salts f o r breeder r e a c t o r s w i l l c o n t a i n 233U and thorium.

However, t h e Therefore, con-

s i d e r a t i o n w i l l be given t o operating t h e MSRF: with a f u e l mixture cont a i n i n g 233U and Th t o demonstrate the c o m p a t i b i l i t y of these c o n s t i t u e n t s and t o provide development information.

Operation with t h e modified f u e l

mixture would follow s u c c e s s f u l operation with t h e i n i t i a l f u e l charge.

6.2.1

Fuel Chemistry A s u b s t a n t i a l a m o ' m t of informatEon about t k e benavior of m d t e r

f l u o r i d e - s a l t mlxtures i n an eiviro_ment l i k e t h a t cf the MSRE i;ae obtained from o u t - c f - p i l e loop experimerAts and f w m short-term, i n t e c s i t y il?-pLle t e s t s .

A11 of t h i s

kigh-

indicates t h a t the

ir?fwmatiU?.

chemistry of t h e MSRE s a l t mixtures is s a t i s f a c t o r y

fl-r

le?g-'verm cpera-

The extended c p e r a t i o n of t h e r e a c t o r w i 7 1 provide

tion.

bs3.

alvl

c.pprrtmity

tc study t h e e f f e c t s , if aQy, of irradiali! r: 3xposinr-e f o r loztg per5oa3s of It w i l l a l s o t e s t t h e adequacy of t h e operating procedures with

time.

regard t o keeping t h e s a i t s f r e e frcm e x t e r n a l con5aminants. Detailed chemical analyses w i l l be perfumed on a l l t h e s a i t samples t h a t a r e obtained.

A n a l y t i c a l i n f o m a t k s will be Fcught tt? t h e ft:Il~;w%-cg

areas :

concentrations of major c o n s t i t a e c t s ( ~ i ,a,~ r U, , F't,

concentrations of f i s s i o n prodixts,

concentrations of corrosion products,

4. 5. 6.

oxide contamination, contamination by o t h e r f o r e i g n species, and reducing power of t h e melt.

We do not a n t i c i p a t e t h a t the f u e l chemistry w i l l impose any operating

l i m i t a t i o n s on t h e r e a c t o r h t a l l t h e resvLts w i l l

c l o s e l y examined

for any unexpected behavior.

2.2

Materials Compatabiiity The demonstratio2 o f s u i t a b l e c o n p a t a b i l i t y o f t h e f-Ael s a l t with

g r a p h i t e and with ITOF-8 i s one of the MSiiE.

TPE

importact c73Jectives ~f the

It i s a l s o d e s i r a b l e +,o determfre t h e f'Lssi,x ard eorri>ife)q p r o d m t

d i s t r i b u t i o n within t h e r e a c t c r syszem a d tc: deternine any cha-cges which occur i n t h e mechanical p r o p e r t i e s of t h e grrtphite c r Y Y c ~ i - 8 as a r e m i t c f t h e long-term exposure tc t'ne Pael s a l t az?d t c a t-i-igh nextror: f l u x .

ZYOF-8 and g r a p h i t e s p c c i s i ~ r ;2s ~ hs t a l l e d near t h e v e r t i r a l c e n k r l i n e of t h e r e a c t m core. The I A sample assembly contal-ing

g r a p h i t e samples extezd t h e fill leigtk ~f tine specimens w i l l be exposed t o d i f f e r e n t l e v e l s

ELL:

CJf

cc t h a t t%? v a r i o

neutrox flux,

A pcrtiw-

6-3 of t h e samples w i l l be removed a t various times throughout t h e e n t i r e l i f e of t h e r e a c t o r , with t h e f i r s t samples being removed a f t e r a period of s i x months t o a year.

Yew specimens w i l l be i n s t a l l e d t o replace those

t h a t are removed. A s e r i e s of c o n t r o l samples, i d e n t i c a l t o t h e

IYOR-8and

graphite

samples i n t h e r e a c t o r core, w i l l be exposed t o f u e l s a l t i n t h e absence of r a d i a t i o n .

The c o n t r o l samples w i l l be subjected t o the r e a c t o r thermal

and salt-exposure h i s t o r y concurrently with t h e r e a c t o r .

Coctrol samples

w i l l be removed and examined on t h e same schedule as t h e r e a c t o r samples.

6.2.2.1

@-s&ite-

The g r a p h i t e samples w i l l be examined f o r shrinkage e f f e c t s , any tendency toward s a l t permeation, changes i n p h y s i c a l o r mechanical propert i e s , and f o r deposition or absorption of f i s s i o n or corrosion products. Carefully machined, measured, and weighed specimens a r e included from both t h e a x i a l and t r a n s v e r s e d i r e c t i o c of a g r a p h i t e s t r i n g e r .

These

w i l l be checked f o r weight gain or l o s s and f o r dimensional changes.

Changes i n t h e mechanical p r o p e r t i e s w i l l be evaluated by bend t e s t s on premachined specimens.

E l e c t r i c a l conductivity measurements w i l l a l s o

be made t o i n d i c a t e changes i n the p h y s i c a l p r o p e r t i e s . Metallographic examinations w i l l be made t o determine i f t h e r e i s any evidence of s a l t p e n e t r a t i o n i n t o t h e g r a p h i t e or if t h e r e i s any s u r f a c e deposition of f i s s i o n o r corrosion products.

Autoradiography

w i l l a l s o be used t o i n d i c a t e if s a l t p e n e t r a t i o n has occurred.

Sample d r i l l i n g s w i l l be analyzed spectographically and chemically t o determine t h e i d e n t i t y and q u a n t i t y of any f i s s i o n products which may be p r e s e n t e i t h e r as a surface deposit or as a r e s u l t of diffksion i n t o t h e graphite. 6.2.2.2

pp18-

There are s i x INOR-8 rods i n t h e sample assembly, and each rod has

been machined t o form 32 t e n s i l e specimens when c u t a t t k e proper locations.

A p o r t i o n of t h e s e specimens w i l l be t e n s i l e t e s t e d a t various

temperatures t o determine the u l t i m a t e and y i e l d s t r e n g t h s and t h e ductility.

Creep t e s t s a t 1250째F w i l l be run on t h e e t h e r specimens t o d e t e r -

mine t h s creep and s t r e s s - r u p t n r e p r o p e r t i e s acd t o determine t h e creep

dixt5lity.

There a r e four specimeis

ir!

t h e sample assembly made from weld-

deposited me%1 which w i l l a l s o be used i n t e n s i l e and creep t e s t s . The specimens w i l l be examined m e t a l l o g r a p h i c a l l y t o determine i f any changes i n microstructure have occurred and t o evaluate any evidence of corrosion by subsurface leaching.

The specimens w i l l a l s o be examined

f o r fission-product deposition 5y spectographic and chemical a n a l y s i s .

6.2.2.3

~gl-agI-Cgo~a~t-Sg1~

The f u e l and coolant s a l t samples w i l l be chemically analyzed f c r t h e build-up corrosion products and oxides.

The f u e l samples w i l l a l s o be

examined by gamma spectroscopy f o r t h e build-up of c e r t a i n f i s s i o n products. Chemical separations a r e p o s s i b l e f o r various f i s s i o n products, b u t t h i s type of a n a l y s i s w i l l n o t be done u n l e s s a s p e c i f i c need develops.

6.2.2.4

pgl-system gfgggs-

The helium offgas stream from t h e f u e l system may c o n t a i n a v a r i e t y of contaminants ranging from t h e rare-gas f i s s i o n products (xenoris and kryptons) t o decomposition products of t h e l u b r i c a t i n g o i l used i n t h e f u e l c i r c u l a t i n g pump.

F a c i l i t i e s w i l l be provided for removing samples

of t h i s gas both a t t h e operating concentration and a f t e r concentrating t h e contaminants on molecular s i e v e material.

The samples w i l l be sub-

j e c t e d t o mass- and gamma-spectrographic analyses to i d e n t i f y t h e coctamin a r t s and measure t h e i r concentrations.

Measurements of t h e lS4Xe t o 136Xe

r a t i o i n t h e offgas w i l l provide independent data on t h e 135Xe poisoning ig

t h e r e a c t o r as w e l l as some information on t h e dynamics of rare-gas

stripping.

The analyses may a l s o provide information about o t h e r v o l a t i l e

f i s s i o n products.

The e x a c t nature of t h e i n f o r m a t i o i t h a t i s obtained

w i l l depend on t h e i d e n t i t y of t h e s p e c i e s t h a t appear i n t h e offgas.

If a sufficielnt q u a n t i t y of f i s s i o n products i s deposited on t h e gasexposed s u r f a c e s of th? f u e l pump, t h e i r presence could be d e t e c t e d by an i n c r e a s e i n pump-tank temperature during shutdown periods. .The equilibrium temperatures of t h e upper pump-tank s u r f a c e w i l l be recorded with t h e cooling a i r off and with t h e system heated and drained during each shutdown perfod.

The temperatures a f t e r power operation w i l l .

then be compared with t h e o r i g i x a l values f o r evidence of an a d d i t i o n a l energy source.

The f u e l pump must be drained and t h e pvmp-tank helium

6-5 purged t o eliminate t h e heating from t h e f i s s i o n products i n t h e gas and i n t h e f u e l s a l t which would tend t o mask t h e heating by s u r f a c e deposits.

6.2.3

Changes i n I)ynamics The t e s t s made during t h e low-power phase (see 4.2.7) and intermediate

power phase (see 5.2.9)

w i l l be repeated a t t h e s t a r t of full-power opera-

t ion. I n a d d i t i o n , t e s t s w i l l be made p e r i o d i c a l l y during full-power operaThese w i l l be p r i m a r i l y f o r t h e purpose of d e t e c t i n g any p o s s i b l e

tion.

unexpected changes i n the dynamic c h a r a c t e r i s t i c s .

Measurement of t h e

noise spectrum w i l l be used f o r t h i s if s t a t i s t i c a l l y r e l i a b l e information can be obtained arovind t h e resonant frequency (- 0.01 c y c l e s / s e c ) .

It i s

expected, however, t h a t it w i l l be necessary t o use control-rod pulse experiments as t h e primary means f o r t h e s e t e s t s . Performance of Components and Equipment

6.2.4

The components and equipment exposed t o f u e l and coolant s a l t are almost a l l of a unique design and are constructed of a unique material (INOR-8).

Many of t h e component designs have been t e s t e d i n t e s t loops

a t or near r e a c t o r conditions, b u t t h e r e i s no a c t u a l long-term r e a c t o r operating experience of e i t h e r t h e components or t h e m a t e r i a l of construc-

It i s t h e r e f o r e Tmportant t o monitor t h e performance of these

tion.

components t o r e v e a l any unforeseen changes i n performance or i n c i p i e n t mechanical f a i l u r e .

It i s a l s o important t o monitor t h e performance of

some of the more conventional eqJipment so t h a t t h e f a i l u r e of t h e s e com-

ponents during important phases of r e a c t o r operation can be avoided as n e a r l y as p o s s i b l e . 6.2.4.1

The a r e a s of p a r t i c t l l a r i n t e r e s t a r e o u t l i n e d below.

Beat-Txagsfey

ESiErngnL

S e v e r a l components i n the r e a c t o r system and i n t h e a u x i l i a r y systems must provide adequate heat t r a n s f e r f o r continued operation of t h e r e a c t o r

fd-11

power.

The heat-removal rate from t h e r e a c t o r depends d i r e c t l y

on the h e a t - t r a n s f e r c h a r a c t e r i s t i c s of t h e primary fuel-to-coolant h e a t exchanger and t h e cooiact-system r a d i a t o r .

Any l o s s i n h e a t t r a n s f e r ,

e i t h e r by t h e buildup of scale, loss of flow, o r by blockage of tubes,

will r e s u l t i n a decrease i n the maximum power l e v e l a t which t h e r e a c t o r can be operated for a given r e a c t o r o u t l e t temperature.

(The u l t i m a t e

6-6 limL5atioi-i 5s t h e miYiLmum s a f e temperature of t h e coolant sal? a t t h e r a d i a t o r o u t l e t , >9005F.) The h e a t - t r a n s f e r c h a r a c t e r i s t i c s of t h e h e a t

exchanger w i l l be deternined p e r t o d i e a l l y by taking t e m p e r a h r e data a t s e v e r a l d i f f e r e n t power l e v e l s .

k computerized procedure i s a v a i l a b l e

which eliminates any eo?stan.t; bEas i n t h e tnermocouple readings and y i e l d s a n averaged, o v e r a l l h e a t - t r a n s f e r c o e f f l c i e n t f o r a l l t h e power l e v e l s .

By observing these h e a t - t r a n s f e r c o e f f i c i e n t s over a period cf time, any tendency toward fouling or plugging of t h e heat exchanger can be detected. Slnce t h e r a d i a t o r has an almost i n f i c i t e v a r i e t y of combinations of

a i r flow and tube exposure f o r any givel? power l e v e l , a t r u e h e a t - t r a n s f e r c o e f f i c i e n t cannot be determined.

However an e f f e c t i v e c o e f f i c i e n t can

be defined and c a l c u l a t e d using standardized procedures.,

This e f f e c t i v e

c o e f f i c i e n t w i l l be evaluated a t s e v e r a l power l e v e l s using p r e s e l e c t e d door aad bypass-damper positions, and t h e r a d i a t o r performance over a period of time can be compared t o the o r i g i n a l performance. The fuel-drain-tank coolers a r e required t o remove t h e fission-product a f t e r h e a t f r o n t h e f u e l s a l t a f t e r a s u s t a i n e d run a t r e l a t i v e l y high power.

There i s not a s u f f i c i e n t h e a t source a v a i l a b l e t o permit t h e

cooling system to be t e s t e d a t f u l l load p r i o r t o nucleay o p e r a t i o n a t

full power.

Xowever, a t r a n s i e n t t e s t using t h e heat c a p a c i t y of t h e s a l t

as a heat source i n d i c a t e d a heat-removal c a p a b i l i t y of 140 kw, which i s more than adequate.

A heat-removal t e s t w i l l be conducted a f t e r t h e r e -

a c t o r has operated f o r a p e r i c d of t i m e a t p a r t load t o determine t h e s t e a d y - s t a t e heat-removal c a p a b i l i t y . Other pieces of heat-exckange equipment whkh a r e reqGired f c r t h e c o n t i m e d c p r a t i o n of t k e r e a c t o r a r e t h e r e a c t o r - , coolant-, and drainc e l i space c c c l e r s , the treated-water cooler, t h e cooling tower, the component-cooling-pump o i l coolers, t h e component-cooling-pump gas cooler, and t h e lube o i l coolers.

The performance of t h i s equipment w i l l be

observed throughout t h e l i f e of t h e r e a c t o r t o insure t h a t adequate performance i s mailntained f o r t h e c o n t i m e d operation of t h e r e a c t o r ,

6 2.4.2 e

mgrgocog&eg

Thermocouples a r e used thronghout the system as c o n t r o l s i g n a l s , t o m c r i t o r the operating temperature of a l l t h e high-temperature compoaents.

6-7 Thermocouple e r r o r s may be introduced by a c t u a l f a i l u r e of the thermocouple, by long-term d r i f t caused by t h e high temperatures, by changes i n heatt r a n s f e r c h a r a c t e r i s t i c s , or by n u c l e a r - r a d i a t i o n e f f e c t s .

Some of t h e

thermocouples may a l s o be influenced by l o c a l nuclear-radiation heating which would cause them t o give an apparently high reading.

Although

s e p a r a t i o n of the various types of e r r o r would be d i f f i c u l t , o v e r a l l changes i n t h e thermocouple performance throughout t h e r e a c t o r system can be determined by s t a t i s t i c a l methods.

A complete set of readings a t isothermal (zero power) conditions f o r

a l l thermocouples reading f u e l - or c o o l a n t - s a l t temperature w i l l be taken, and a s t a t i s t i c a l a n a l y s i s can be made t o determine the mean temperature and t h e standard deviation.

S i m i l a r analyses w i l l be run during t h e

operating l i f e of t h e reactor, and t h e mean temperatures and standard deviations w i l l be observed f o r changes i n thermocouple performance. P r o b a b i l i t y p l o t s w i l l a l s o be made t o determine if s i g n i f i c a n t new mechanisms occur during t h e operating l i f e which cause s t a t i s t i c a l v a r i a t i o n of t h e readings.

The thermocouple readings w i l l a l s o be reviewed t o

determine whether the i n d i v i d u a l thermocouples maintain t h e i r same posit i o n s r e l a t i v e t o t h e mean. Preliminary data has i n d i c a t e d t h a t the thermocouples on the r a d i a t o r should be grouped and analyzed s e p a r a t e l y from those on t h e remainder of t h e f u e l and coolant systems.

Additional groupings w i l l be made as re-

quired t o o b t a i n a maximum of information.

For example, it may be reason-

a b l e t o s e p a r a t e those i n high r a d i a t i o n f i e l d s from those i n lower f i e l d s t o assess t h e radiation-exposure e f f e c t . Records w i l l a l s o be maintained of t h e a c t u a l f a i l u r e s and t h e causes of t h e failures where t h e s e are known.

6.2.4.3

g e s t g r g ZnG @gu&al&m-

A l l t h e r e a c t o r piping and components which a r e exposed t o e i t h e r f u e l o r coolant s a l t a r e heated e l e c t r i c a l l y t o i n s u r e t h a t t h e metal surfaces i n contact w i t h t h e molten s a l t remain above t h e f r e e z i n g p o i n t of t h e s a l t .

Three g e n e r a l types of i n s u l a t i o n are used i n t h e system.

The main piping i n s i d e the r e a c t o r c e l l and t h e h e a t exchanger use remov-

able heater u n i t s w i t h i n t e g r a l reflective insulation.

The o t h e r components

6-8 t h e r e a c t o r and drain-tank c e l l s a r e enclosed i n furances which a r e i n s u l a t e d w i t h more conventional low-conductivity i n s u l a t i o n .

Some of t h e

piping, p a r t i c u l a r l y i n the coolant c e l l where d i r e c t maintenance i s f e a s i b l e , has permanently i n s t a l l e d Calrod h e a t e r s and conventional insulation. The heat l o s s of the r e f l e c t i v e i n s u l a t i o n i s expected t o i n c r e a s e about 10% because of changes i n e m i s s i v i t y .

The performance of t h e low-

conductivity i n s u l a t i o n , and a l s o t h e r e f l e c t i v e type, may change because of cracks and c r e v i c e s developing through t h e i n s u l a t i o n and through t h e j o i n t s of t h e component furnaces.

Any increases i n h e a t l o s s from e i t h e r

type i n s u l a t i o n w i l l be determined during shutdown periods by s e t t i n g a l l t h e h e a t e r s back t o t h e i r o r i g i n a l 1200Â°F s e t t i n g s and recording t h e equilibrium temperatures with t h e system drained.

The r e s u l t i n g tempera-

t u r e s w i l l then be compared t o t h e o r i g i n a l reading, and any decrease i n temperature i s an i n d i c a t i o n of increased h e a t l o s s .

While it would be

p o s s i b l e t o determine a q u a n t i t a t i v e number f o r t h e i n c r e a s e i n h e a t l o s s by s e t t i n g t h e h e a t e r s t o o b t a i n t h e o r i g i n a l temperatures, t h e time req u i r e d t o make t h e s e adjustments throughout t h e system i s p r o h i b i t i v e l y long.

Some q u a n t i t a t i v e information about t h e o v e r a l l performance may

a l s o be gained from observation of t h e h e a t loads on t h e space c o o l e r s i n the c e l l s . Records w i l l a l s o be kept of h e a t e r or power-lead f a i l u r e s and of t h e conditions and causes of these f a i l u r e s . 6.2.4.4

CigulStLng mng s n g m&e-oil_pa_cLages

The f u e l c i r c u l a t i n g pumps may be s u b j e c t t o f i v e types of s l o w d e t e r i o r a t i o n of performance.

These a r e (1) a s l o w wearing of t h e bearings and

o i l seals, (2) a buildup of s c a l e i n t h e c o o l i n g - o i l passages i n t h e s h i e l d plug and t h e s h a f t , (3) f a t i g u e damage due t o temperature cycling,

(4) a slow plugging of t h e xenon-stripper j e t s , and (5) r a d i a t i o n damage e f f e c t s t o t h e drive-motor e l e c t r i c a l i n s u l a t i o n and t o t h e motor-bearing lubricant.

The coolant pâ&#x20AC;&#x2122;mp i s s u s c e p t i b l e t o only t h e f i r s t t h r e e of

t h e above items.

Unless a completely unprecedeited c o r r o s i v e o r e r o s i v e

a t t a c h occurs on t h e hydraulic p a r t s , a l o s s i n hydraulic performance i s not anticipated.

6-9 The l u b r i c a t i 2 g - o i l packages a s s o c i a t e d w i t h each of t h e main c i r c u l a t i n g pumps may a l s o be s u b j e c t t o a slow d e t e r i o r a t i o n of performance by

a decrease i n h e a t t r a n s f e r a t t h e cooler or by a plugging of t h e f i l t e r t o an e x t e n t t h a t it cannot be c l e a r e d by standard procedures.

There a r e

standby o i l pumps with independent power s u p p l i e s on each o i l package s o t h a t t h e e l e c t r i c a l or mechanical f a i l u r e of one pump does not r e q u i r e

a r e a c t o r shutdown.

The circulating-pump-motor power input and speed, t h e pump temperat u r e s , and t h e r a t e of s e a l - o i l leakage w i l l be monitored f o r long-tern changes i n t h e circulating-pump performance.

A thermal-cycle h i s t o r y of

the pumps w i l l a l s o be maintained t o insure t h a t t h e c a l c u l a t e d s a f e l i f e

of t h e pumps w i l l n o t be exceeded and t o determine if t h e r e a r e any premature failures Although a l l t h e damaging and wear processes a r e g e n e r a l l y continuous, most of them have threshold values, and t h e p r o b a b i l i t y of d e t e c t i n g an i n c i p i e n t f a i l u r e w i t h a s i g n i f i c a n t l y long advance warning i s r e l a t i v e l y

small.

The wearing of t h e lower o i l s e a l and t h e decrease i n h e a t t r a n s -

f e r from t h e s h i e l d plug a r e p o s s i b l e exceptions where a t r e n d could be followed.

6.2.4.5

-Frgege-Vglxeg

Freeze valves are used t o prevent t h e undesired t r a n s f e r of s a l t from one p a r t of t h e system t o another.

Freeze valves 103, 204, and 206, which

hold t h e me1 and coolant s a l t i n t h e i r r e s p e c t i v e systems, a r e a l s o required t o m e l t within s p e c i f i e d times.

Each f r e e z e valve has a series

of c o n t r o l modules which maintain t h e valve p a r t s a t the proper tempera-

tures. The performance of t h e f r e e z e valves and modules w i l l be evaluated by m a i n t a i n i i g a h i s t o r y of t h e f r e e z e and thaw cycles and a h i s t o r y of t h e adjustments and replacements of t h e controlmodules.

A history w i l l

a l s o be maintained of any u n i n t e n t i o n a l thaws and any o t h e r malfunctions which might occur.

6.2.4.6

g-geze-F&arIggs-

The main fuel- arid coolant-system piping i n s i d e t h e r e a c t o r c e l l i s connected w i t h a t o t a l of f i v e p a i r s f r e e z e flanges s o t h a t t h e major

6-10 compor?ents can be removed and replaced.

The flanges have a buffer-gas

and leak-detector system which insures t h a t any leakage i s gas leakage i n t o the system and a l s o permits the measurement of the t o t a l leakage r a t e of b u f f e r gas from the flange j o i n t . The long-term performance of t h e f r e e z e f l a n g e s w i l l be evaluated

by maintaining a h i s t o r y of the buffer-gas leakage r a t e s and a h i s t o r y of the opening and closing of t h e flanges.

A thermal-cycle h i s t o r y w i l l

a l s o be maintained t o insure t h a t t h e c a l c u l a t e d s a f e l i f e i s not exceeded and t o determine if t h e r e a r e any premature f a i l u r e s .

6.2.4.7

~ a ~ i ~ t ~ r - a ~ d - R &=x&sgrg ~dLa~o~

The r a d i a t o r and r a d i a t o r enclosure provide t h e heat-load demand and the load c o n t r o l of the r e a c t o r .

The load demand i s determined by t h e

combination of door position, bypass-damper p o s i t i o n , and t h e number of main blowers operating.

The load may be s e t by e i t h e r manually s e t t i n g

t h e door and damper p o s i t i o n s and by manually energizing t h e proper blowers,

or by using an automatic load-demand switch t h a t a c t u a t e s t h e doors, t h e damper, and t h e blowers i n a preprogrammed sequence.

The r a d i a t o r doors

may a l s o be closed r e l a t i v e l y r a p i d l y t o remove t h e heat l o a d from t h e reactor. The performance of t h e r a d i a t o r i s p a r t i a l l y covered i n Sections

6.2.4.1,

.2, and .3, and t h e r e f o r e t h e mechanical performance of t h e doors,

t h e door-actuating mechanism,

t h e bypass danper, t h e main blowers, and the

automatic loading system w i l l be considered i n t h i s s e c t i o n .

The per-

formance of these components w i l l be evaluated by p e r i o d i c a l l y checking t h a t t h e doors and t h e damper a c t u a t e smoothly and a t t h e p r e s c r i b e d rates under both normal and scram conditions and by checking t o i n s u r e t h a t t h e p o s i t i o n i n d i c a t o r s agree with the a c t u a l p o s i t i o n s .

The automatic

loading system w i l l be checked t o i n s u r e a r e l a t i v e l y smooth i n c r e a s e and decrease i n load over t h e range of operation.

A d e t a i l e d h i s t o r y w i l l be

maintained of any f a i l u r e s which occur and of any adjustments which a r e r e q u i r e d on any of t h e r a d i a t o r components.

6 2.4.8

@gtLpgen++tLog

A l a r g e v a r i e t y of both nuclear and process instrumects and con-

t r o l s a r e p r e s e n t i n t h e r e a c t o r and t h e a u x i l i a r y systems.

These

6-11 instruments and c o n t r o l s w i l l be c a l i b r a t e d and a d j u s t e d p e r i o d i c a l l y during shut-down periods and a l s o a t any time an instrument appears t o be excessively i n error. A d e t a i l e d record w i l l be maintained on each instrument of t h e changes

t h a t occur from c a l i b r a t i o n t o c a l i b r a t i o n , t h e adjustments t h a t are made during t h e c a l i b r a t i o n , and of any a c t u a l f a i l u r e s which occur.

6.2.4.9

co@;oL

gods-agd-Qixeg

The nuclear c h a r a c t e r i s t i c s of t h e r e a c t o r a r e such t h a t f a s t - a c t i n g c o n t r o l rods were not required.

A f l e x i b l e design was chosen so t h a t a

s i n g l e v e s s e l p e n e t r a t i o n could be used and t h e rod thimbles could be bent t o avoid i n t e r f e r e n c e with t h e g r a p h i t e sampler.

The rods a r e a

s e r i e s of short, c y l i n d r i c a l poison elements s l i p p e d over a f l e x i b l e core. Development t e s t s have shown t h a t t h e rods may s t r e t c h during t h e e a r l y l i f e of t h e control-rod assemblies.

A p o s i t i o n c a l i b r a t i o n p o i n t was

b u i l t i n t o t h e control-rod thimbles which w i l l be used t o p e r i o d i c a l l y check t h e rods f o r elongation.

The rod p o s i t i o n i n d i c a t o r s w i l l a l s o be

c a l i b r a t e d a t the same time. The f l e x i b l e design with two bends prevents a free g r a v i t y rod drop which i s t h e common method f o r scramming a r e a c t o r .

However, t h e rods

have been s p e c i f i e d to, and do, drop with a minimum a c c e l e r a t i o n of 12 ft/sec2.

Tests w i l l be conducted throughout t h e r e a c t o r l i f e t o i n s u r e

t h a t t h i s a c c e l e r a t i o n i s maintained and t o observe any changes from t h e o r i g i n a l value.

The rods w i l l a l s o be observed f o r e r r a t i c motion which

would be an i n d i c a t i o n of s t i c k i n g or binding. When the r e a c t o r i s operated a t power f o r s u s t a i n e d periods of time, t h e control-rod worth w i l l eventually begin t o decrease because of t h e "burnup" of t h e poison m a t e r i a l .

Rod-drop t e s t s t o evaluate t h e c o n t r o l -

rod worth w i l l be conducted a t a p p r o p r i a t e i n t e r v a l s .

A more a c c u r a t e

c a l i b r a t i o n of t h e control-rod worth w i l l be made, i f t h e r e s u l t s of t h e rod-drop tests i n d i c a t e t h a t t h i s i s needed. The control-rod d r i v e s operate i n a high r a d i a t i o n f i e l d i n s i d e t h e b i o l o g i c a l s h i e l d i n g and have been s p e c i f i e d t o operate i n a f i e l d of

lo5

rad/hr.

The d r i v e s w i l l be observed f o r r a d i a t i o n damage e f f e c t s on

t h e e l e c t r i c a l ir:sulation,

t h e l u b r i c a n t s , and t h e switches.

The d r i v e s

w i l l a l s o be observed f o r mechanical f a i l u r e or o t h e r malfunction.

6-12

6.2.4.10 EecLoz ~egsgl-Agsgm~l~ The normal surveillance of the reactor vessel and core graphite is done by the examination of the graphite-and-INOR-8 sample assembly as outlined in Section 6.2.2.

However, should the need arise, the 10-inch

access flange can be removed which, will allow five of the graphite stringers to be removed and will permit a visual examination of parts of the vessel interior using remote viewing techniques. The capability also exists for making a more limited visual inspection each time the graphite sample assembly is removed. These inspections will be made at times when deemed necessary or desirable and not on a

scheduled basis.

ORNL-TM- 911

Internal Distribution

1. MSRP Director's Office

23 24. 25 26. 27 * 28.

Rm. 219, 9204-1 R . K. Adams G. M. Adamson R . G. A f f e l L. G. Alexander R . F. Apple C . F. Bzes J. M. Baker S . J . Ball W. Sarthold H. F. Bzuman S . E . Beall M. Bender E. S . Bettis F. F. Blankenship R . Blumberg E. G. Bohlmann C . 5. Borkowski G. H. Eurger S . Cantor W. L. Carter G.. I. Cathers E. L. Compere W. H. Cook L. T. Corbin J . L. Crowley F . L. C u ller J . M. a l e

D. G. Davis

3. 4. 5. 6. 7.

8. 9.

10. 11. 12.

13 14. 15 16. 17 18. 19 20. 21.

22. 9

30 S. 31 R . 32. F. 33 J . 34 E . 9

D. E. A. H. J. C.

36 * 37 38 39 40. 41. R. 9

J. Ditto G. Donnelly A . Doss R. Engel P. Epler E. Ferguson N. Fray P. Fraas A . Friedman H. Frye, Jr. H. Gabbard B. Gallaher

42. 43.

44. 45. 46-55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65. 66. 67. 68. 69. 70.

71. 72. 73. 74. 75. 76. 77. 78. 79. 80.

81. 82. 83. 84. 85. 86. 87. 88. 89. 90. 91. 92.

W. R . G r i m e s G. Grindell

A. R. P. P. G. F. P. V. T. P. R.

M. C

H. Guymon H. Harley

.?!I

Haubenreich

M. A. G. D. L. R. J. J.

Zebert Heddleson tierndon

. R.

21. W.

H. T. S. D. A. J. J. R. M.

S. J. I. W. A. B. I.

R. N.

Yoit Hudson Kasten Ked1 Kelly Kennedy Kerlin Kerr Kirslis Knowles Krakoviak Krewson Lane Lindauer Lundin Lyon

E. G . MacPherson

R. E . MacPherson C . D. M a r t i n C . E. Mathews H. E . McCoy E. C . McCurdy H. F. McDuffie C . K. McGlothlan L. E . McNeese A. S . Meyer A . J. M i l l e r R. L. Moore P. Patriarca E. R. B y n e A . M. Perry H. B. Piper B. E . Prince J . L. Redford

ORNL-TM-911 Internal Distribution (continued)

93 M. 94 R . 95 H. 96 M. 97 H. 98. A . 99 D. 9

100. 101. 102. 103.

104.

H. J. M. A. P.

105. W.

106.

107. R.

108. H. 109. J .

Richardson C . Robertson C . Roller W. Rosenthal W. Savage W. Savolainen Scott E. Seagren H. S h a f f e r J . Skinner N. Smith G. Smith F. Spencer Spiewak C. Steffy H. Stone R. Tallackson

110. R . E . Thoma 111. G . M. Tolson 112. D. B. Trauger 113. W. C . U l r i c h 114. B. H. Webster 115. A . M. Weinberg 116. J . R. Weir, Jr. 117. K. W. West 118. M. E. Whatley 119. G. D. Whitman 120. J . C . White 121. H. D. W i l l s 122. L. V. Wilson 123-124. C e n t r a l Research Library 125-126. Document Reference Section 127-129. Laboratory Records 130. Laboratory Records - RC

External D i s t r i b u t i o n

131. A . Giambusso, AEC-Washington 132. C . L. Matthews, AEC OR0

133 134. 135 136. 137-138. 139-153

T. W. McIntosh, AEC Washington H. M. Roth, Division of Research and Development, AEC-OR0 W. L. Smalley, Reactor Division, AEC-OR0 R . F. Sweek, AEC Washington Reactor Division, AEC OR0 Division of Technical Information Extension