Understandings API ICP653 Reading 8- Q&A Practices Work Sheet 05 Part1
My self study note for API653 ICP 储罐认证, Q&A作业学习 24th February 2016
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AST Tanks
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AST Tanks
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Adobe Acrobat Reader Hotkeys Ctrl + G = find again Ctrl + L = full screen Ctrl + M = zoom to Ctrl + N = go to page (insert number in box) Ctrl + Q = quit program Ctrl + + = zoom in Ctrl + - = zoom out Ctrl + 0 = fit in window Ctrl + 1 = actual size Ctrl + 2 = fit width Ctrl + 3 = fit visible Ctrl + 4 = reflow Ctrl + Shift + A = deselect all Ctrl + Shift + F = search query Ctrl + Shift + G = search results Ctrl + Shift + J = cascade windows Ctrl + Shift + K = tile windows horizontally Ctrl + Shift + L = tile windows vertically Charlie Chong/ Fion Zhang
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Fion Zhang at Xitang 24th February 2016
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API 653 Exam Administration -- Publications Effectivity Sheet FOR: November 2015, March 2016 and July 2016 Listed below are the effective editions of the publications required for this exam for the date(s) shown above. API Recommended Practice 571, Damage Mechanisms Affecting Fixed Equipment in the Refining Industry, Second Edition, April 2011
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API 653 Exam Administration -- Publications Effectivity Sheet FOR: November 2015, March 2016 and July 2016 Listed below are the effective editions of the publications required for this exam for the date(s) shown above. API Recommended Practice 571, Damage Mechanisms Affecting Fixed Equipment in the Refining Industry, Second Edition, April 2011
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ATTENTION: Only the following sections / mechanisms from RP 571 are included on the exam: Section 3, Definitions Par. 4.2.7 Brittle Fracture 4.2.16 Mechanical Fatigue 4.3.2 Atmospheric Corrosion 4.3.3 Corrosion Under insulation (CUI) 4.3.8 Microbiologically Induced Corrosion (MIC) 4.3.9 Soil Corrosion 4.3.10 Caustic Corrosion 4.5.1 Chloride Stress Corrosion Cracking (Cl-SCC) 4.5.3 Caustic Stress Corrosion Cracking (Caustic Embrittlement) 5.1.1.10 Sour Water Corrosion (Acidic) 5.1.1.11 Sulfuric Acid Corrosion
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API Recommended Practice 575, Inspection of Atmospheric and LowPressure Storage Tanks, Third Edition, April 2014 API Recommended Practice 577 – Welding Inspection and Metallurgy, Second Edition, December 2013 API Standard 650, Welded Tanks for Oil Storage, Twelfth Edition, March 2013 with Addendum 1 (September 2014), Errata 1 (July 2013), and Errata 2 (December 2014). API Recommended Practice 651, Cathodic Protection of Aboveground Petroleum Storage Tanks, Fourth Edition, September 2014. API Recommended Practice 652, Lining of Aboveground Petroleum Storage Tank Bottoms, Fourth Edition, September 2014 API Standard 653, Tank Inspection, Repair, Alteration, and Reconstruction, Fifth Edition, November 2014.
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American Society of Mechanical Engineers (ASME), Boiler and Pressure Vessel Code, 2013 Edition i. ASME Section V, Nondestructive Examination, Articles 1, 2, 6, 7 and 23 (section SE-797 only) ii. Section IX, Welding and Brazing Qualifications (Welding Only) ď Ž
See end of this study note for API Official BOK
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http://greekhouseoffonts.com/
The Magical Book of Tank Inspection ICP
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闭门练功
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闭门练功
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Section 1 Introduction
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Pre-Test: API653 Maths Q1. Find the minimum acceptable shell plate thickness of the first course of an existing AST. tmin = Minimum acceptable thickness ? D H G S E
= Nominal diameter of tank, in feet = Height of tank in feet = Specific gravity of contents = Maximum allowable stress = Joint efficiency of tank
tmin = 2.6(H-1)DG/SE tmin = 0.82151�
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120 48 1 21000 .85
Q2. Find the corrosion rate of an AST given the following information. Original thickness = .875” Measured thickness = .625 Years since last thickness measurement = 11 Corrosion Rate N = (.875-.625)/11 = 0.0227”/year Q3. Using the corrosion rate determined in problem number 2, what would the remaining life expectancy of this tank be if the minimum required thickness is 0.436”? Remaining life = (.625-.436)/0.0227 = 8.325 years
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Q4. Shell settlement evaluation measurements are to be taken on a 146 feet diameter AST. Given the following formula, how many elevation measurements would be required? N= D/10 N = 146/10 =14.6 or 15 used 16 N is the minimum required number of settlement measurement points, but no less than eight. All values of N shall be rounded to the next higher even whole number. The maximum spacing between settlement measurement points shall be 32 ft. Q5. Using the information in number four, does this number meet the requirements of API-653, which does not permit the measurement points to exceed 32 feet? Spacing = πD/16 = 28’ (OK)
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Q6. Find the throat of a right angle fillet weld with a weld leg length of .4375 inches. Throat = 0.707 x .4375 = 0.309” Q7. Using the following information, what is the maximum vertical length (also known as critical length), in inches, over which hoop stresses are assumed to “average out” around local discontinuities? Diameter of the tank is 136 feet, the least thickness in an area of corrosion, exclusive of pits, is determined to be .563” L = 3.7√(Dt2) = 32.376”
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Q8. A 6 inch nozzle is to be placed in the tank shell of an AST. The shell course where the nozzle will be installed is .875� thick. What is the required area of reinforcement? Area removed = D x t = 6 3/4 x .875 = 5.91 in.2
If a shell plate thicker than required is used for the product and hydrostatic loading (see 5.6), the excess shell-plate thickness, within a vertical distance both above and below the centerline of the hole in the tank shell plate equal to the vertical dimension of the hole in the tank shell plate, may be considered as reinforcement, and the thickness T of the nozzle reinforcing plate may be decreased accordingly. In such cases, the reinforcement and the attachment welding shall conform to the design limits for reinforcement of shell openings specified in 5.7.2. Charlie Chong/ Fion Zhang
Q9. The maximum ultrasonic thickness measurement interval shall be five years when the corrosion rate is not known. What is the interval based on a known corrosion rate? The tank information is as follows: Initial thickness of the tank was 1.0625”, the actual thickness is .815”, the calculated required thickness is .473”, the tank has been in service for 16 years with no measurements taken since it was installed. Corrosion rate = (1.0625-0.815)/16 = 0.01547”/year N = (.815-.473)/ Cr = 22.1years Used 15 years Q10. What is the circumference of an AST that is 96 feet in diameter? Circum = πD = 301.1’
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Q11- Practice problems #1: Problem #1 Find “S” when tmin, D, H, G, and E are known where: D=78, H=29, G = 1, E=.85, and tmin =.602 tmin = 2.6(H-1)DG/SE S = 2.6(H-1)DG/tminE = 11097psi Q12: Problem #2 Find E when D, H, G, S, G, and tmin are known where: D =128, H=60, S = 22,300 G = .87, and tmin = 1.125 E = 2.6(H-1)DG/tminS = 0.68
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Q13: Problem #3 Find “D” when H, E, S, G, and tmin are known where: H=45, E=.90, S=22500, G= .7 and tmin =.9375 D = tmin(SE)/ (2.6(H-1)G) = 237’ Q14: Problem #4 Find “St” when E, Ht, D, G, and tmin are know where: E = .80, Ht = 54, D= 70, G = 1 and tmin =.4325 St = 2.6(H-1)D/ tminE = 27878psi
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Q15: Problem #5 Find “C” when D and H are know where D = 60, H = 54 C = 0.14D2H = 27216 Barrels
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Post Test: Q1. What is the required hydrostatic test height (Ht) of an AST given the following data? Maximum allowable hydrostatic stress (St)= 21350 Diameter of the tank = 110 feet Hydrostatic test shell thickness (tmin) is .625� Shell joint efficiency = 70% Use API-653 2.3.3.1 formula for tanks to be hydrostatically tested. ANS: Ht = tminStE/2.6D + 1 = 33.66’ Q2. What is the area of a tank bottom that is 121 feet in diameter? ANS: 22/7 x 60.52 = 11503 feet 2
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Q3. A reinforcing plate is installed around a nozzle in the first course of an AST. What is the throat dimension of the ½� leg fillet weld around the periphery of the reinforcing plate. ANS: 0.707 x 0.5 = 0.3535
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Q4. What is the minimum acceptable thickness of the bottom course of an existing AST that is 135 feet in diameter, maximum fill height is 56.5 feet? The product stored in the tank has a specific gravity of .87 and all shell buttwelds were 100% radiographically examined. The yield strength of the material is 28,000 and the tensile strength is 60,000. Use API-653 paragraph 2.3.3.1. ANS: S is the maximum allowable stress in pound force per square inch (lbf/in.2); use the smaller of 0.80Y or 0.429T for bottom and second course; S = 22400, 25740 used 22400psi tmin = 2.6(H-1)DG/SE = 0.454�
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Q5. What is the required area of reinforcement for a 14 NPS nozzle installed in a shell course that is 1.0625� thick. Use API 650 Paragraph 3.7.2.1 ANS: 14 1/8 x 1.0625 = 15 in.2 Q6. A bulge is noted in a tank bottom, what is the maximum height of the bulge permitted if the radius of the inscribed circle is 10.8 feet? Use API-653 Appendix B 3.3 ANS: BB = 0.37R = 0.37(10.8) = 4�
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Q7. If the throat of a fillet weld is .309, what is the leg length of the weld? ANS: .309/.707 = 0.437� Q8. An AST is 175 feet in diameter. How many tank settlement survey points are required? Use API-653 paragraph 10.5.1.2. ANS: D/10 = 18
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Q9. Do the number of settlement measurement locations and maximum spacing, calculated in problem 8, comply with API – 653? Use API –653 Paragraph 10.5.1.2 ANS: Circu = (22/7 X 175)/18 <32 (OK) Q10. What is the design liquid level of an AST that is 140 feet in diameter, thickness of the bottom or first course is .765”, stress of the material is 21300. The specific gravity of the product to be stored is 1 and no corrosion allowance is needed nor provided. ANS: 0.765(21300)/(2.6x 140) +1 = H = 45.77’
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Section 1 - Introduction Q1. API-653 covers which of the following types of tanks? a) Carbon and low alloy steel tanks built to ASME Section VIII, Div.1 b) Carbon and low alloy steel tanks built to ASME Section X c) Carbon and low alloy steel tanks built to API - 650 and 12C d) Carbon and low alloy steel tanks built to API - 510 ANS: C Q2. API-653 provides the requirements for construction of which of the following? a) Process pressure vessels b) Aboveground petroleum storage tanks c) LNG Storage spheres d) This standard does not provide construction requirements ANS: D
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Q3. API-653 provides for all but which of the following with regard to aboveground storage tanks? a) Repair b) Operation c) Relocation d) Alteration ANS: b Q4. The scope of API-653 is limited to all of the following except? a) Tank foundation b) Tank Bottom c) Tank roof d) Tank mixing motor ANS: d
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Q5. The API-653 standards states that many of the requirements for design, welding, and materials of API-650 and API-12C can be applied with regard to _____. a) Repair, inspection, rating, and alteration. b) Repair, personnel assignment, maintenance, and inspection. c) Inspection, product in storage, rating, and alteration. d) Alteration, refinery equipment, electrical controls, and repair. ANS: a Q6. In the application of the requirements for welding, design, and materials of API-650 or API-12C to in-service aboveground storage tanks (AST), which of the following code or standard takes precedence? a) ASME Section VIII, Pressure Vessels b) API-12C c) API-653 d) API-650 ANS: c
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Q7. The API-653 Standard may only be applied to aboveground storage tanks (AST) that have been constructed to and meet the requirements of API650. a) True b) False ANS: B Q8. The use of API-653 is intended for organizations that have personnel who are technically trained and experienced in which of the following? a) All ASME, AWS, ASNT, and API Codes and Standards b) Tank design, fabrication, repair, construction, and inspection c) Refinery operations, safety requirements, personnel management, and refinery design d) Mechanical integrity program, OSHA regulations compliance program, and Process Safety Management ANS: B
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Q9. When design and construction details are not given and not available in the original construction standard, then details that will provide a level of integrity equal to the current edition of what Code or Standard must be used? a) ASME Section VIII, Division 1, Pressure Vessels b) ASME Section VIII Division 2, Alternative Rules for Pressure Vessels c) API- 650, Welded Steel Tanks for Oil Storage d) API-12C Steel Storage Tanks for Oil Storage ANS: C Q10. Ultimate responsibility for compliance with this standard rests with ____? a) The Owner/Operator b) The Owner/Operatorâ&#x20AC;&#x2122;s Inspector c) The repair organization of the Owner/Operator d) The manufacturer of the AST ANS:A
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Q11. According to API-653, if any provision presents a direct or implied conflict with any statutory regulation, the regulation governs. What governs if API-653 requirements are more stringent than the statutory regulation? a) The statutory regulation applies in all cases b) The conflict must be submitted to the American Petroleum Institute for resolution c) The owner/operator has the option of applying the requirement best suited to the situation d) The API-653 requirements shall govern ANS: D Q12. Safe working practices shall comply with what requirements concerning confined space entry? a) Procedures must comply with any trade developed safety precautions b) Procedures must comply with any federal or state regulations c) Procedures need only comply with owner/operator/s requirements d) Procedures need only comply with NFPA requirements ANS: B
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Answers to API-653 Section 1, Introduction
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Section 2 Suitability for Service
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Q1. When must an evaluation, to determine the suitability for continued use, be conducted? a) Evaluations shall be conducted when a tank inspection reveals a change has occurred from the original physical condition of the tank. b) Evaluations shall be conducted at least annually c) Evaluations shall be conducted at an interval not to exceed the calculated tank inspection frequency. d) Evaluations shall be conducted once each ten years of service ANS: a Q2. What factors are required for consideration when performing an evaluation for continued use of an AST? a) Only those listed in API-653 b) The recommended list of considerations provided in API-510 can be modified to suit this purpose c) Engineering analysis and judgement required for each situation d) Only those items requested by the Certified Aboveground Storage Tank Inspector ANS: c Charlie Chong/ Fion Zhang
Q3. Roof plates corroded to an average thickness of less that ____ inch in any ___ square inch area shall be repaired of replaced. a) 0.9 inch in any 100 square inch area b) 0.09 inch in any 10 square inch area c) 0.09 inch in any 144 square inch area (1 square foot) d) 0.09 inch in any 100 square inch area ANS: d Q4. The method of inspecting roof support members shall be acceptable to whom? a) The manufacturer of the AST b) The responsible inspector c) The Owner/Operatorâ&#x20AC;&#x2122;s design engineering department d) The operations manager ANS: b
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Q5. During the inspection of fixed roof support members, particular attention must be given to . a) Severe external corrosion of the roof plate where support structures are attached b) Severe internal corrosion of pipe columns c) Severe internal corrosion of the roof plate where support structures are attached d) Deterioration of wind girders at the point of attachment ANS: b Q6. Inspection of floating roofs is limited to roof plates and pontoons. a) True b) False ANS: b
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Q7. Evaluation of existing floating roofs shall be based on the criteria of a) API-650, Appendix C for external floating roofs and Appendix H for internal floating roofs b) API-510 Paragraph 6.4.3 for external floating roofs and 6.5.3 for internal c) ASME Section VIII, Div 1 Appendix C for external floating roofs and Appendix H for internal d) ASME Section VIII, Div. 2 Alternative Rules ANS: a Q8. What API Standard or Recommended Practice must be used for evaluating the effects of design partial vacuum on tank roofs? a) API Standard 620 b) API Standard 650 c) API Recommended Practice 651 d) API Recommended Practice 652 ANS: a
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Q9. Above what operating temperature shall API Standard 650, Appendix M, be considered before changing the service of a tank? a) 500째F b) 400째F c) 300째F d) 200째F ANS: d Q10. Under what conditions may a tank be operated at a temperature lower than the original design? a) When the requirements for impact testing of ASME Section VIII, Division 1 have been met b) When the requirements of the applicable standard or API Standard 650 have been met c) When the requirements of ASTM Specification A-370 have been met d) When the requirements of ASTM Specification A-20 have been met ANS: b
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Q11. Flaws, deterioration, or other conditions that might adversely affect the performance or structural integrity of the shell of an existing tank must be evaluated. Personnel experienced in tank design shall conduct the evaluation. This analysis shall take into account any of the following except a) Fluid static head b) Internal and external pressure c) Organization that manufactured the tank d) Seismic loads ANS: c Q12. Of the following, which is not an option available to the owner/operator if it is not possible to satisfy the requirements for minimum thickness calculations for a welded tank? a) Repair damaged areas b) Reduce allowable liquid level c) Retire the tank d) Reduce the fill rate so the tank fills slower and applies pressure gradually ANS: d Charlie Chong/ Fion Zhang
Q13. Out-of-roundness, buckled areas, flat spots, and peaking and banding of welded joints are all examples of _____. a) Shell Distortions b) Flaws c) Discontinuities d) Severe damage ANS: a Q14. Shell distortions require the tank to be immediately removed from service and inspected. a) True b) False ANS: b
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Q15. Flaws such as cracks or laminations shall be thoroughly examined to determine their nature and extent and the need for repairs. a) True b) False ANS: a Q16. What if anything should be done with cracks in the shell-to-bottom weld? a) These cracks can be sealed with caulking and the tank returned to service b) The welds can have a cover weld pass applied over them to prevent leakage c) Cracks of this type are critical and the tank must be retired from service since repairs are prohibited. d) Cracks in the shell-to-bottom weld are critical and shall be removed and the weld repaired ANS: d
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Q17. Internal pitting and pitting rates in the anticipated service, corrosion of weld joints (weld and heat affected zone), weld joint cracking history, and stresses placed on the bottom plates by roof support loads and shell settlement are all examples of causes of what type of failure? a) Annular ring failure b) Shell plate failure at first shell course c) Bottom failure d) Fatigue failure due to repeated jacking of floor plates ANS: c
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Q18. Underside corrosion (normally in the form of pitting), inadequate drainage resulting in surface water flowing under the tank bottom, lack of an annular plate ring when required, uneven settlement that results in high localized stresses in the bottom plates, and inadequate provision for movement of roof support columns and other supports are all examples of causes of what type of failure? a) Shell plate failure at first course b) Bottom failure c) Failure of support columns due to hydraulic compression d) Creep cracking failure ANS: b
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Q19. Of the following what has historically not been a cause of bottom failures? a) Non-homogeneous fill under the tank bottom b) Rock or gravel foundation pads with inadequately filled-in surface voids c) Inadequate inspection frequency d) Inadequately supported sumps ANS: c Q20. Where would you look to find the basis for cathodic protection systems for the underside of tank bottoms? a) API Recommended Practice 651 b) API Recommended Practice 652 c) API Standard 2015 d) API Standard 2207 ANS: a
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Q21. Where would you look to find procedures and practices for protecting tank bottoms with internal lining? a) API Recommended Practice 651 b) API Recommended Practice 652 c) API Standard 2015 d) API Standard 2207 ANS: b Q22. What two methods may be used in quantifying the remaining thickness of tank bottoms? a) Drilling and actual measurement b) Ultrasonic and radiography c) Deterministic and probabilistic d) Detailed stress analysis and plate deformation measurement ANS: c
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Q23. Unless a stress analysis is performed, what is the minimum thickness of bottom plates in the critical zone? a) Smaller of ½ the original bottom plate thickness or 50% of tmin of the lower shell course but not less than 0.1 inch. b) Smaller of ¼ the original bottom plate thickness or 25% of tmin of the lower shell course but not less than 0.1 inch. c) Smaller of ¾ the original bottom plate thickness or 75% of tmin of the lower shell course but not less than 0.1 inch. d) Smaller of ½ the original bottom plate thickness or 50% of tmin of the lower shell course but not less than 0.01 inch. ANS: a
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Q24. When repairing internal pitting for the extension of in-service operating period, the repair shall be by any of the following methods except. a) Pit welding b) Brazing c) Overlay welding d) Lap Patching ANS: b
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Q25. The thickness of the bottom plate projection beyond the shell, measured at the toe of the weld of the outside bottom-to-shell fillet weld shall be not less than? a) 0.25 inch b) 0.01 inch c) 0.50 inch d) 0.10 inch ANS: d Q26. The projection of the bottom plate beyond the toe of the shell-to-bottom weld shall be at least? a) 0.125 inch b) 0.250 inch c) 0.375 inch (3/8â&#x20AC;?) d) 0.500 inch ANS: c
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Q27. An aboveground storage tank contains a fluid with a specific gravity of less than one. The thickness of the plate in the first course is 7/8â&#x20AC;?. What is the minimum thickness of the annular plate ring, seismic loading is not a consideration, and the stress in the first course is 27,850 pound per square inch? a) 0.22 inch b) 0.31 inch c) 0.20 inch d) 0.23 inch ANS: b Q28. An aboveground storage tank contains a fluid with a specific gravity of greater than one. The thickness of the plate in the first course is 7/8â&#x20AC;?. What is the minimum thickness of the annular plate ring, seismic loading is not a consideration, and the hydrostatic test stress in the first shell course is 27,850 pound per square inch? a) 1 / 4 inch b) 3 / 8 inch c) 9 / 32 inch (0.28125â&#x20AC;?) d) 11 / 32 inch ANS: c Charlie Chong/ Fion Zhang
Q29. Settlement, erosion, cracking, and deterioration of concrete are all examples of which of the following principle modes of failure or deterioration? a) Annular plate ring failure b) Shell-to-bottom weld failure c) Deterioration of walkways and roadways d) Deterioration of foundations ANS: d Q30. To ensure suitability for service, what is the minimum permitted frequency of tank foundation inspection? a) Annually b) Every five years c) Monthly d) Periodically ANS: d
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API653: 4.5 Tank Foundation Evaluation 4.5.1 General 4.5.1.1 The principal causes of foundation deterioration are settlement, erosion, cracking, and deterioration of concrete initiated by: calcining, attack by underground water, attack by frost, and attack by alkalies and acids. To ensure suitability for service, all tank foundations shall be inspected periodically (see 6.3).
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Q31. Distortion of anchor bolts and excessive cracking of concrete structures may be indications of what two conditions? a) Serious foundation settlement of a tank overpressure uplift condition b) Inferior material used in the anchor bolts and the concrete structure c) Over tightening of the anchor bolts and improper mixing of the concrete d) The tank was struck by lightning and wind caused movement of the tank ANS: a
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Answers to API-653 Section 2, Suitability for Service
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Section 3 Brittle Fracture Considerations
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Q1. Incidents of tank failure due to brittle fracture have occurred shortly after erection during hydrostatic testing or in all but which of the following incidents? a) On the first filling in cold weather b) After a change to a higher temperature service c) After a change to a lower temperature service d) After a repair or alteration ANS: b
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Q2. The risk of tank failure due to brittle fracture is considered minimal after what condition(s)? a) The tank has demonstrated its ability to withstand the combined effects of maximum liquid level (highest stresses) and highest operating temperature b) The tank has demonstrated its ability to withstand the combined effects of intermediate liquid level (highest stresses) and lowest operating temperature c) The tank has demonstrated its ability to withstand the combined effects of maximum liquid level (highest stresses) and lowest operating temperature d) The tank has demonstrated its ability to withstand the combined effects of maximum liquid level (highest stresses) and intermediate operating temperature ANS: c
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Q3. If it is decided to change the service to a more severe service, it is necessary to a) Consider the need for pneumatically testing the entire tank b) Consider the need to recalculate the effectiveness of all reinforcement of openings c) Consider the need for hydrostatic testing d) Consider removing all previous welded repairs and have them redone ANS: c Q4. If a tank shell thickness is less than _____ inch, and an evaluation in accordance with Section 2 of API-653 has been performed, the risk of brittle fracture is considered to be minimal. a) 0.01 b) 0.10 c) 0.05 d) 0.50 ANS: d
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Q5. No known tank failures attributed to brittle fracture have occurred at shell metal temperatures of _____째F and above. a) -20 b) 20 c) 40 d) 60 ANS: d Q6. According to industry experience and laboratory tests, what membrane stress is required to caused failure due to brittle fracture? a) 6 ksi b) 7 ksi c) 10 ksi d) 12 ksi ANS: b
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Q7. What is the lowest temperature that a tank, constructed of carbon steel of unknown toughness, may be used? The maximum thickness of the shell is .625” a) 40°F b) 45°F c) 50°F d) 55°F ANS: A Q8. What is the purpose of Figure 3-1 of API-653? a) Provides a procedure to be used in the evaluation of the remaining life of tank bottom plates b) Provides a procedure to be used in the evaluation of the likelihood of floating roof pontoon failure c) Provides an assessment procedure for evaluating aboveground storage tanks operating at 15 psi d) Provides an assessment procedure for evaluating atmospheric aboveground storage tanks ANS: D Charlie Chong/ Fion Zhang
Figure 5.2â&#x20AC;&#x201D;Exemption Curve for Tanks Constructed from Carbon Steel of Unknown Material Specification:
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Answers to API-653 Section 3, Brittle Fracture Considerations
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Section 4 Inspection
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Q1. What is the purpose of periodic in-service inspection? a) The purpose of periodic in-service inspection, assure job security for inspectors b) The purpose of periodic in-service inspection, assure proper operation of AST c) The purpose of periodic in-service inspection is to assure continued tank integrity d) The purpose of periodic in-service inspection is to assure OSHA compliance ANS: c Q2. Of the following, which is not a consideration that must be addressed in determining inspection intervals for ASTs? a) Corrosion prevention systems b) Inspection interval of other equipment located near the tank under consideration c) Changes in service (including changes in water bottoms) d) Previous inspection results ANS: b Charlie Chong/ Fion Zhang
Q3. What methods of inspection must be considered when establishing inspection frequencies? a) On-stream core sample inspection b) On-stream nondestructive inspection c) In-service aerial inspection d) In-service groundwater inspection ANS: b Q4. Close visual inspections of aboveground storage tanks, from the ground, are required. Owner/operator personnel who may be other than the Authorized Inspector may perform this inspection. The interval of such inspections shall not exceed: a) At least every five years or 1/4 the corrosion rate life of the shell whichever is less b) 12 months c) 6 months d) 1 month ANS: d
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Q5. All tanks shall be given a visual external inspection, by an Authorized Inspector, at what frequency? a) Inspection conducted at least every 20 years or at the quarter corrosion rate of the bottom whichever is less b) Inspection conducted at least every 5 years or at the quarter corrosion rate of the bottom whichever is less c) Inspection conducted at least every 5 years or at the quarter corrosion rate of the shell whichever is less d) Inspection conducted at least every 20 years or at the quarter corrosion rate of the shell whichever is less ANS: c
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Q6. External ultrasonic thickness measurements of the shell, while the tank is in service, can be a means of determining rate of uniform corrosion. The extent of UT measurements shall be determined by the owner/operator. What is maximum interval of such thickness measurements when the corrosion rate is not known? a) Five years b) Three years c) One year d) Every three months until the corrosion rate is established ANS: a
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Q7. The minimum thickness of a tank was established at 0.585 inch. The shell was fabricated from 3/4 inch plate and included a 0.125 inch corrosion allowance. The tank has been in service for eight years and current ultrasonic thickness measurements reveal an average thickness of 0.712 inch. Based on this information determine when the next ultrasonic thickness measurements will be required. a) Fifteen years b) Thirteen years c) Eleven years d) Nine years ANS: corrosion rate = 0.75-0.712/8 = 0.00475â&#x20AC;?/year. Interval = (0.712- 0.71)/(2x0.00475) = 0.21years Interval = (0.712-0.585)/(2x0.00475) = 13.36 years (b)
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Q8. Internal inspections are primarily required to do all but which of the following? a) Ensure the internal surfaces of the tank are thoroughly cleaned periodically b) Identify and evaluate any tank bottom settlement c) Ensure that the bottom is not severely corroded and leaking d) Gather data necessary for the minimum bottom and shell thickness assessments ANS: a
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Q9. When can the required internal inspection be performed by some method other than visual inspection? a) Substitution of the visual inspection is never permitted b) If the internal inspection is required solely for determining the condition and integrity of the tank bottom c) If the internal inspection is required solely for determining the condition and integrity of the tank critical zone d) If the internal inspection is required solely for determining the condition and integrity of the tank roof support structure ANS: b Q10. According to API-653, all tanks shall have a formal internal inspection conducted at intervals defined by this standard. Who is required to conduct the visual inspection? a) The corrosion engineer b) The person designated by the Authorized Inspector c) The authorized Inspector d) The person designated by the owner user ANS: c Charlie Chong/ Fion Zhang
Q11. Intervals between internal inspections shall be determined by the corrosion rates measured during previous inspections or anticipated based on experience with tanks in similar service. The internal inspection interval shall not exceed how many years? a) Ten years b) Fifteen years c) Twenty years (without RPB) d) Twenty-five years ANS: d Q12. What is the minimum thickness permitted at the next inspection for a tank bottom designed with a means to provide detection and containment of a bottom leak? a) 0.01 inch b) 0.10 inch c) 0.50 inch d) 0.05 inch ANS: d
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API653: 6.4.2.1 Initial Internal Inspection Interval The initial inspection interval shall not exceed 20 years for tanks without a Release Prevention Barrier, or 30 years for tanks with a Release Prevention Barrier. 6.4.2.1.2 As an alternative to establishing the initial interval in accordance with Section 6.4.2.1 and Table 6.1, the initial internal inspection date and reassessment can be established using Risk Based Inspection (RBI) assessment per 6.4.2.2.2. These assessments may establish an initial inspection interval exceeding 10 years but shall not exceed 20 years for tanks without a Release Prevention Barrier, or 30 years for tanks with a Release Prevention Barrier except as follows……….. 6.4.2.2 Subsequent Internal Inspection Interval When using the corrosion rate procedures of 6.4.2.2.1 the maximum subsequent internal inspection interval shall be 20 years for tanks without a Release Prevention Barrier, or 30 years for tanks with a Release Prevention Barrier. (20 without RPB, 30 with RPB & indefinite period of time if suggested by RBI?) Charlie Chong/ Fion Zhang
Q13. In cases where corrosion rates are not known and similar service experience is not available, the bottom plate actual thickness shall be determined by inspection(s) within how many years? a) 25 years b) 20 years c) 15 years d) 10 years ANS: d Q14. Which of the following is a recognized alternative to internal inspection interval described in API-653? a) Risk-based Inspection procedures (RBI) b) Hydrostatically testing the tank every five years c) Performing complete calculations for minimum required thickness of the tank shell and bottom d) API-653 does not permit any alternatives to the internal inspection intervals ANS: a
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Q15. Of the following, which would not be a factor to be considered in a Riskbased assessment of a tank? a) Availability and effectiveness of inspection methods and quality of data collected b) The methods used for determining the thickness of the shell and bottom plates c) Effectiveness of corrosion mitigation methods d) Names of all operators since the initial start-up of the tank ANS: d Q16. The owner/operator is required to maintain complete record file consisting of three types of records. Which of the following is not one of the three types of records. a) Repair/alteration history b) Fill cycles c) Construction d) Inspection ANS: b
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Q17. General inspection reports shall include which of the following? a) Metal thickness measurement, repairs, conditions found, settlement measurements, and recommendations b) Metal thickness measurement, repairs, operational upsets, settlement measurements, and recommendations c) Metal thickness measurement, repairs, conditions found, name of organization performing environmental impact study, and recommendations d) Metal thickness measurement, list of all personnel who have worked on the tank since the last inspection, conditions found, settlement measurements, and recommendations ANS: a
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Answers to API-653 Section 4, Inspection
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Section 5 Materials
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Q1. All new materials used for repair, alteration, and reconstruction shall conform to which of the following? a) The existing material code at the time of original construction b) The latest NFPA Code c) The current applicable tank standards d) Any ASME Code specification for P-1 material ANS: c Q2. All shell plates and bottom plates welded to the shell shall be identified. Material identified by any of the following except _____ does not require further identification? a) Original contract drawings b) API name plates c) Suitable documentation d) Owner/operator's experience with similar tanks in similar service constructed of similar material ANS: c
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Q3. Each individual plate for which adequate identification can not be made; the plate shall be _______. a) Subjected to chemical analysis and mechanical tests as required in ASTM A6 and A370 including Charpy V-Notch b) Subjected to chemical analysis and mechanical tests as required in ASTM A20 and A333 including Charpy V-Notch c) Subjected to Brinell hardness analysis and mechanical tests as required in ASTM A6 and A370 including Charpy V-Notch d) Subjected to Brinell hardness analysis and mechanical tests as required in ASTM A20 and A333 including Charpy V-Notch ANS: a
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Q4. Under what condition does API-653 require two tension specimens shall be taken at right angles to each other from a corner of each plate? One of those specimens must meet the specification requirements. a) When the direction of rolling is not definitely known b) When the welding will be conducted at a temperature less than 32ยบF c) When the plate is not a full size plate and may be installed with the grain running vertical d) When the material is not a P-1 material ANS: a
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Q5. Even when a material is identified, all shell plates and bottom plates welded to the shell shall meet what minimum requirements? a) The chemistry and mechanical properties of material specified for the application with regard to thickness and design temperature given in ASME Section II, Part A b) The chemistry and mechanical properties of material specified for the application with regard to thickness and design temperature given in API Standard 650 c) The chemistry and mechanical properties of material specified for the application with regard to thickness and design temperature given in the owner/operator's engineering design d) The chemistry and mechanical properties of material specified for the application with regard to thickness and design temperature given in the contract for the tank repair, alteration, or reconstruction ANS: b :
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Q6. Is it permissible to reuse existing rolled structural shapes? If so what specification applies? a) Yes, existing rolled structural shapes shall meet the requirement of ASTM A-20 as a minimum b) Yes, existing rolled structural shapes shall meet the requirement of ASTM A-370 as a minimum c) Yes, existing rolled structural shapes shall meet the requirement of ASTM A-6 as a minimum d) Yes, existing rolled structural shapes shall meet the requirement of ASTM A-7 as a minimum ANS: c Q7. Flange material must meet the minimum requirements of the material specifications of the current applicable standard. a) True b) False ANS: b
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Q8. Fasteners shall meet the material specifications of the current applicable standard. a) True b) False ANS: b Q9. If existing plates are to be used to reconstruct the tank, they shall be checked for which of the following? a) Chemical compatibility with other plates used in the reconstruction b) Excessive corrosion and pitting c) Mechanical strength including impact properties d) Inadequately reinforced openings ANS: b
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API653: 7.3 Original Materials for Reconstructed Tanks 7.3.1 Shell and Bottom Plates Welded to the Shell 7.3.1.1 All shell plate materials and bottom plates welded to the shell shall be identified. Materials identified by original contract drawings, API nameplates, or other suitable documentation do not require further identification. Material not identified shall be tested and identified by the requirements as outlined in 7.3.1.2. After identification, determination shall be made as to suitability of the material for intended service. 7.3.2 Structural Existing rolled structural shapes that are to be reused shall meet the requirement of ASTM A7 as a minimum. New structural material shall meet the requirements of ASTM A36 or ASTM A992 as a minimum. NOTE ASTM A7 was a steel specification that was discontinued in the Fourth Edition of API 650, 1970.
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7.3.3 Flanges and Fasteners 7.3.3.1 Flange material shall meet the minimum requirements of the material specifications in the as-built standard. 7.3.3.2 Fasteners shall meet the material specifications of the current applicable standard.
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7.3.2 Structural Existing rolled structural shapes that are to be reused shall meet the requirement of ASTM
A7 as a minimum. New structural material shall meet the requirements of ASTM A36 or ASTM A992 as a minimum. NOTE ASTM A7 was a steel specification that was discontinued in the Fourth Edition of API 650, 1970.
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7.3.2 Structural Existing rolled structural shapes that are to be reused shall meet the requirement of ASTM A7 as a minimum. New structural material shall meet the requirements of ASTM A36 or ASTM A992 as a minimum. NOTE ASTM A7 was a steel specification that was discontinued in the Fourth Edition of API 650, 1970.
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7.3.2 Structural Existing rolled structural shapes that are to be reused shall meet the requirement of ASTM A7 as a minimum. New structural material shall meet the requirements of ASTM A36 or ASTM A992 as a minimum. NOTE ASTM A7 was a steel specification that was discontinued in the Fourth Edition of API 650, 1970.
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7.3.2 Structural: ASTM A7 as a minimum.
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7.3.3 Flanges and Fasteners 7.3.3.1 Flange material shall meet the minimum requirements of the material specifications in the as-built
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standard.
7.3.3.2 Fasteners shall meet the material specifications of the
current applicable standard.
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Answers to API-653 Section 5, Materials
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Section 6 Design Considerations of Reconstructed Tank
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Q1. Design considerations other than normal product loading shall be specified by the _____. a) Organization performing the reconstruction b) Authorized Inspector c) Owner/operator d) Registered professional engineer contracted by the repair organization ANS: c Q2. Weld joint details shall meet the requirements of which of the following? a) API Standard 650 b) ASME Section IX only c) The applicable standard d) AWS D1.1 Structural Welding Code ANS: d
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Q3. The thickness to be used for each shell course when checking tank design shall be based on: a) Measurements taken within 30 days prior to relocation b) Measurements taken within 60 days prior to relocation c) Measurements taken within 120 days prior to relocation d) Measurements taken within 180 days prior to relocation ANS: d Q4. The maximum liquid level for hydrostatic test shall be determined by using which of the following? a) The nominal thickness of each shell course at the time of original construction b) The actual thickness measured for each shell course c) The anticipated thickness for each shell course at the time of next thickness measurements d) Twice the anticipated thickness for each shell course at the time of next thickness measurements ANS: b
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Q5. The joint efficiency and allowable stress levels for existing welded joints that are not to be removed and replaced shall be based on which of the following? a) Original construction standard b) Original degree and type of inspection c) Current construction standard d) Current degree and type of inspection ANS: b Q6. Replacement and new penetrations shall be designed, detailed, welded, and examined to meet what requirements? a) The current applicable standard b) The original standard of construction c) The requirements of the Authorized Inspector d) The requirements of the owner/operator ANS: a
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Q7. Existing penetrations shall be evaluated for compliance with what requirements? a) The current applicable standard b) The original standard of construction c) The requirements of the Authorized Inspector d) The requirements of the owner/operator ANS: b Q8. With regard to seismic design, reconstructed tanks shall be built to meet the stability requirements of: a) The requirements of the owner/operator b) The requirements of the Authorized Inspector c) The original standard of construction d) The applicable standard ANS: d
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API653: 8.3 Existing Weld Joints Existing weld joints shall meet the requirements of the as-built standard. 8.4.5 The joint efficiency and allowable stress levels used for the design liquid level calculations shall be consistent with the design method used and with the degree and type of examination made on welded joints. The joint efficiency and allowable stress levels for existing welded joints that are not to be removed and replaced shall be based on the original degree and type of examination.
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API653: Table 4.2â&#x20AC;&#x201D;Joint Efficiencies for Welded Joints
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Answers to API-653 Section 6, Design
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Section 7 Tank Repairs & Alterations
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Q1. The basis for repairs and alterations shall be equivalent to which of the following? a) API-653 b) API-650 c) API-510 d) API-570 ANS: b Q2. The minimum dimension for a replacement shall plate shall be _____ inches or ____ times the thickness of the replacement plate whichever is ______. a) 12, 12, greater b) 12, 12, lesser c) 18, 18, greater d) 18, 18, lesser ANS:a
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9.2.2 Minimum Dimensions of Replacement Shell Plate 9.2.2.1 The minimum dimension for a replacement shell plate is 12 in. or 12 times the thickness of the replacement plate, whichever is greater. The replacement plate may be circular, oblong, square with rounded corners, or rectangular with rounded corners except when an entire shell plate is replaced. See Figure 9.1 for typical details of acceptable replacement shell plates.
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Q3. Unless an entire shell plate is replaced, the replacement plate may be circular, oblong, square or rectangular provide the corners are a) Provided with a radius of at least 1 inch (2â&#x20AC;??) b) Provided with a radius of at least 3% of the short dimension of the plate c) Provided with a radius of at least 3 inches d) Provided with rounded corners ANS: D Q4. Prior to welding the new vertical joints, the existing horizontal joints shall be cut for a minimum distance of _____ inches beyond the new vertical joints. a) Six b) Eight c) Twelve d) Sixteen ANS: c 9.3.1.4 The shape of the repair plate may be circular, oblong, square, or rectangular. All corners, except at the shell to bottom joint, shall be rounded to a minimum radius of 2 in. The nozzle reinforcing plate shapes of API 650, Figure 5-8, are also acceptable. Charlie Chong/ Fion Zhang
Q5. Vertical joints shall be welded before the horizontal joints. a) True b) False ANS: a Q6. For existing shell plates over ½â&#x20AC;? thick, the outer edge of the butt weld, attaching the replacement shell plate shall be at least _____ times the weld thickness or _____ inches whichever is greater from the outer edge of any existing butt-welded shell joints. a) 12, 10 b) 10, 12 c) 8, 10 d) 10, 8 ANS: c
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Q7. For existing shell plates ½” thick and less, the outer edge of the butt weld, attaching the replacement shell plate may be reduced to _____ inches from the outer edge of vertical joints or _____ inches from the outer edge of horizontal joints. a) 10, 8 b) 9, 6 c) 6, 9 d) 6, 3 ANS: d Q8. For existing shell plates over ½” thick, the outer edge of the butt weld, attaching the replacement shell plate shall be at least _____ times the weld size or _____ inches, whichever is greater, from the edge (toe) of the fillet weld attaching the bottom shell course to the bottom. This rule does not apply if the replacement shell plate extends to and intersects with the bottom-toshell joint at approximately _____ degrees. a) 8, 10, 45 b) 8, 10, 90 c) 8, 10, 60 d) There are no exceptions ANS: b
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Figure 9.1â&#x20AC;&#x201D;Acceptable Details for Replacement of Shell Plate Material
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Figure 9.1â&#x20AC;&#x201D;Acceptable Details for Replacement of Shell Plate Material
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Q9. The edge of any vertical weld joint attaching a replacement plate shall be at least how far from the edge of the weld joint in the annular plate ring or sketch plate? a) Eight inches b) Ten inches c) Twelve inches d) Six inches ANS: 3” or 5t? (dimension “C”?) Q10. Lapped patch shell repairs are an acceptable form of repair for buttwelded, lap-welded, and riveted tank shell only when specified by: a) The Authorized Inspector b) Repair organization c) The insurance company d) The owner/operator ANS: d
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Q11. Lapped patch shell repairs are not permitted on shell courses exceeding what thickness? a) ½ inch b) ž inch c) 1 inch d) 1 Ÿ inch ANS: a Q12. When a lapped patch shell repair is used, what is the minimum thickness permitted for the repair plate? a) Not less than .25 inch b) Not less than .1875 inch (3/16) c) Not less than .50 inch d) Not less than .375 inch ANS: b
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Q13. Repair plates for lapped patch repairs may square or rectangular in shape. These plates must be provided with a corner radius of at least what dimension? a) They shall be rounded to a minimum radius of 1 inch b) They shall be rounded to a minimum radius of 2 inches c) They shall be rounded to a minimum radius of 3 inches d) They shall be rounded to a minimum radius of 4 inches ANS: b Q14. The maximum dimension of the lapped patch repair plate vertically and horizontally shall not exceed: a) 24 inches vertically and 36 inches horizontally b) 36 inches vertically and 48 inches horizontally c) 48 inches vertically and 72 inches horizontally d) There are no maximum dimensions ANS: c
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Q15. The minimum lapped patch repair plate dimension is what length? a) 6 inches b) 8 inches c) 10 inches d) 12 inches ANS: 4â&#x20AC;?? API653: 9.3.1.7 The maximum vertical and horizontal dimension of the repair plate is 48 in. and 72 in., respectively. The minimum repair plate dimension is 4 in. The repair plate shall be formed to the shell radius. Q16. Is it permissible to install a shell opening and its reinforcement within a properly designed lapped patch shell repair? a) Yes b) No ANS: b
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Q17. When a lapped patch repair plate is used to reinforce the thickness of a shell, which of the following is correct? a) The repair plate thickness shall be based on the latest edition of API650 and 653 using a joint efficiency not exceeding 0.35 b) The repair plate thickness shall be based on the applicable standard of construction and API Standard 653 using a joint efficiency not exceeding 0.35 c) The repair plate thickness shall be based on the latest edition of API650 and 653 using a joint efficiency not exceeding 0.70 d) The repair plate thickness shall be based on the applicable standard of construction and API Standard 650 using a joint efficiency not exceeding 0.70 ANS: b
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Q18. With regard to the thickness of the repair plate at the perimeter of the repair plate, when a lapped patch repair plate is used to reinforce the thickness of a shell, which of the following is correct? a) The repair plate shall not exceed the thickness of the shell plate by more than 1/4th but no more than 1/8th inch. The maximum repair plate thickness is 1/2inch. b) The repair plate shall not exceed the thickness of the shell plate by more than 1/3rd but no more than 1/4th inch. The maximum repair plate thickness is 1/2inch. c) The repair plate shall not exceed the thickness of the shell plate by more than 1/3rd but no more than 1/8th inch. The maximum repair plate thickness is 1/2inch. d) The repair plate shall not exceed the thickness of the shell plate by more than 1/4th but no more than 1/3rd inch. The maximum repair plate thickness is 1/2inch. ANS: c
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Q19. Lapped patch repair plates may be used to repair small leaks or minimize the potential of leaks from isolated pitting. The requirements for thickness and design are the same as for reinforcement of shell thickness. This type of repair may not be used to repair small leaks if what condition(s) exists? a) The leak is located anywhere in the first shell course within 12 inches of a vertical joint b) The leak of pit is in an area of the shell where there is a product to atmosphere interface c) There is a possibility of severe environmental impact should the repair fail d) If exposure of the fillet weld to the product would produce crevice corrosion or if a corrosion cell is likely to occur between the shell plate and the repair plate ANS: d
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Q20. An alteration to a tank shell by the addition of new plate material shall be performed in accordance with what standard? a) Current API 650 and latest addenda b) API 650 edition and addenda applicable at the time of original tank construction c) Applicable standard d) Tanks may not be altered by increasing height ANS: c Q21. Repairs to existing shell penetrations shall be in accordance with a) API Standard 650 b) API Standard 653 c) API Standard 510 d) National Board Inspection Code ANS: b
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9.8 Addition or Replacement of Shell Penetrations 9.8.1 New shell penetrations (addition or replacement) shall be in accordance with material, design, and stress relief requirements of API 650, Section 5.7 and in accordance with 9.8.2 through 9.8.6 of this standard. 9.9 Alteration of Existing Shell Penetrations 9.9.1 Existing shell penetrations may be altered if the altered details comply with the requirements of API 650, Section 5.7 including the requirements for minimum reinforcing area and the requirements for spacing of welds around connections.
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Q22. API 653 permits the addition of reinforcing plates to existing unreinforced nozzles. What requirement is necessary to add this reinforcement to the inside of the tank? a) The reinforcement plate may not be added to the inside of the plate b) A telltale hole shall be drilled through the shell opposite the reinforcement plate c) The reinforcement plate is the same material as the nozzle and is attached to the nozzle by full penetration weld d) Sufficient nozzle projection exists ANS: c Q23. The addition or replacement of shell penetrations shall be in accordance with a) API-650 b) API-650 and API 653 c) API-650 and API 510 d) API-650 and AMSE Section VIII, Division 2 ANS: b
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9.7 Repair of Shell Penetrations 9.7.1 Repairs to existing shell penetrations shall be in compliance with API 650, Section 5.7. 9.7.2 Reinforcing plates may be added to existing unreinforced nozzles when deemed appropriate. The reinforcing plate shall meet all dimensional and weld spacing requirements of API 650, Section 5.7. See Figure 9.7 and Figure 9.8 for acceptable details. 9.7.3 As an alternative, the reinforcing plates may be added to the inside of the tank provided that sufficient nozzle projection exists.
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Q24. Installation or replacement of shell penetrations greater than 2 inches shall be installed with the use of an insert plate if what condition(s) exists? a) The penetration is no closer than 12 inches to an existing penetration b) The shell plate is greater than ½â&#x20AC;? thickness and the shell plate material does not meet current metal temperature criteria c) The penetration is no closer than 10 inches to an existing penetration d) The shell plate is greater than 3/16â&#x20AC;? thickness and the shell plate material does not meet current metal temperature criteria ANS: d Q25. An 8 inch diameter penetration is to be installed in a shell which requires an insert plate. What is the minimum permitted diameter of the insert plate? a) Eight inches b) Twelve inches c) Sixteen inches d) Twenty inches ANS: d
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Q26. An insert plate containing an opening with a reinforcing plate is to be installed in a tank. The reinforcing plate diameter is thirty-two inches. What is the minimum diameter of the insert plate? a) The insert plate must be 32 inches in diameter b) The insert plate must be 44 inches in diameter c) The insert plate must be 32 inches in diameter plus the diameter of the opening d) The insert plate must be 32 inches in diameter plus twice the diameter of the opening ANS: b Q27. If an integral reinforcement design is used, the thickness of the insert plate, at its periphery and for a distance of 2t from the edge of the weld, shall be the same thickness as the shell. If it is not, the insert plate shall have a ______ taper to match the shell plate thickness. a) 1:2 b) 1:3 c) 1:4 d) 1:5 ANS: c
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Q28. When it is necessary to install a new tank bottom above an existing bottom, it may be necessary to alter existing shell penetrations. This procedure may require the existing reinforcing plate to be removed and a new reinforcement plate added. This is not permitted when what condition exists? a) The assembly was originally hardness tested b) The existing assembly was not impact tested c) The existing assembly was fabricated from re-claimed material d) The existing assembly was stress relieved ANS: d Q29. New reinforcing plates shall be installed in accordance with Fig. 7-2a of API-653. In order to maintain weld spacing, what shape reinforcing plate is permitted? a) Oval b) Diamond c) Tombstone d) Circular is the only permitted shape ANS: c
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Q30. No welding or weld overlays are permitted within the “Critical Zone” except for welding of widely scattered pits, cracks in the bottom plates, the shell-to-bottom weld, or where the bottom or annular plate is being replaced. a) True b) False ANS: b Q31. API Standard 653 defines the “Critical Zone” for repairs to tank bottoms as what? a) That portion of the bottom or annular plate within 3" from the inside edge of the shell, measured radially inward b) Within the annular plate ring, within 12 inches of the shell, or within 12 inches of the inside edge of the annular plate ring c) That portion of the bottom or annular plate within 6" from the inside edge of the shell, measured radially inward d) Within the annular plate ring, within 3" of the shell, or within 12 inches of the inside edge of the annular plate ring ANS: a
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Q32. If more extensive repairs are required within the â&#x20AC;&#x153;Critical Zoneâ&#x20AC;? than those listed in 7.10.1.2, what must be done with the bottom plate? a) As long as the repairs do not involve the bottom plate, nothing needs to be done b) The bottom plate welded to the shell shall be cut out and a new plate installed c) The bottom plate shall be subjected to suitable nondestructive examination to ensure it has not be adversely affected by the repair d) The bottom plate and the bottom shell course shall be replaced as an assembly ANS: b Q33. When it is necessary to install a new bottom plate over an existing bottom plate, a suitable ______ material cushion such as sand, gravel or concrete shall be used between the old bottom and the new bottom. a) Drainage b) Compacted c) Non-corrosive d) Non-conductive ANS: c
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Q34. When a new tank bottom has been installed in a floating roof tank, what consideration must given to the floating roof level? a) The floating roof will find its own level b) The support legs can be jacked up or shortened by the same amount as the thickness of the cushion and new bottom plate c) The support legs can be jacked up or shortened by the same amount as the thickness of the cushion d) The support legs can be jacked up or shortened by the same amount as the thickness of the new bottom plate ANS: b
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Q35. Which of the following is not acceptable when removing an existing tank bottom, with regard to the separation of the shell from the tank bottom? a) Cutting the shell parallel to the tank bottom a minimum of ½” above the bottom to shell weld b) Removing the entire shell to bottom attachment weld including penetration and heat affect zone c) Removing the entire shell to bottom attachment weld by arc gouging and/or grinding d) Cutting the shell parallel to the tank bottom a minimum of ¼” above the bottom to shell weld ANS: d 9.10.2.3 When removing an existing tank bottom, the tank shell shall be separated from tank bottom either by: a) cutting the shell parallel to the tank bottom a minimum of 1/2 in. above the bottom-to-shell weld (cut line B-B as shown in Figure 10.1), or
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Q36. For installation of a new tank bottom in a tank with shell plates of unknown toughness, not exempted in Table 10-1 of API-653, new welds in the bottom or annular ring shall be spaced at least the greater of _____ inches or ____t from existing vertical weld joints in the bottom shell course. (t is the thickness of the bottom shell course) a) three, five b) six, five c) five, three d) five, six ANS: a Q37.What is the minimum thickness of new roof plates for supported cone roofs? a) 7/16” b) 5/16” c) 3/16” d) 1/16” ANS: c
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Q38. The nominal thickness of new roof plates for self-supporting roofs shall be equal to or greater than _____ inch not to exceed _____ inch. a) 1/4th, 5/8th b) 5/16th, 1/2 c) 3/16th, 5/16th d) 3/16th, 1/2 ANS: c Q39. Repairs to internal floating roofs shall be made in accordance with the original construction drawings. To what requirements shall repairs be made if the original construction drawings are not available? a) The original construction standard b) Appendix H of API Standard 650 (internal floating roof) c) Appendix G of API Standard 650 (supported Al doom roof) d) Appendix C of API Standard 650 (external floating roof) ANS: b
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Q40. To minimize evaporation losses and reduce potential hazard to workers, no more than ____ of the roof seal system should be out of an in-service tank at one time. a) One-eighth b) One-fourth c) One-half d) Three-quarters ANS: b Q41. Mechanical damage to floating roof perimeter seals shall be repaired or replaced. How are buckled parts handled? a) They shall be replaced b) They may be straightened in place c) They may be heated and bent back into position d) They may be removed straightened and re-installed ANS: a
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Q42. With regard to installation of primary and secondary seals, what must be done if the roof rim thickness is less than 0.10 inch. a) The roof rim shall be thoroughly inspected for damage and corrosion, if it is satisfactory then nothing further needs to be done b) It shall be replaced. The new roof rim shall be 3/16 inch thickness minimum c) It shall be replaced. The new roof rim shall be 1/4 inch thickness minimum d) The tank must be condemned and dismantled ANS: b Q43. What is the maximum hot tap connection permitted in an in-service tank with a minimum shell thickness of 3/8 inch? The material is of recognized toughness. a) NPS 6 b) NPS 8 c) NPS 14 d) NPS 18 ANS: c
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Q44. The owner/operator requires a connection to be made in an in-service tank. The shell material is of unknown toughness and the thickness is 1.25â&#x20AC;?. The minimum design metal temperature is 45°F. What is the maximum diameter hot tap connection that may be installed in this tank? a) NPS 18 b) NPS 14 c) NPS 8 d) NPS 4 ANS: d Q45. The minimum height of tank liquid relative to the hot tap location shall be at least ______ during the hot tapping operation. a) The tank liquid shall be at least 3 feet below the hot tap location b) The tank liquid shall be at least 1 foot above the hot tap location c) The tank liquid shall be at least 3 feet above the hot tap location d) The tank liquid shall be at least 1 foot below the hot tap location ANS: c
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Q46. It is permissible to perform hot taps on the roof of a tank or within the gas/vapor space. a) True b) False ANS: b
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Q47. The owner/operator requires an NPS 3 ½ nozzle to be installed in an inservice tank. The tank is 110 feet in diameter, 60 feet maximum fill height, shell thickness at the point of hot tap is .75”, and the material is of unknown toughness with a minimum design metal temperature of 38°F. This nozzle is to be installed adjacent to an existing nozzle. What is the minimum spacing between these nozzles? a) Minimum distance is 22.24” b) Minimum distance is 9.08” c) Minimum distance is 19.08” d) Minimum distance is 2.24” ANS: √(RT) = 22.25” A 9.14.3 Preparatory Work 9.14.3.1 Minimum spacing in any direction (toe-to-toe of welds) between the hot tap and adjacent nozzles shall be equivalent to the square root of RT where R is the tank shell radius, in inches, and T is the shell plate thickness, in inches.
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Q48. When installing a pipe nozzle into an in-service tank, how shall the pipe nozzle be prepared? a) The pipe nozzle must be cut to the contour of the tank and prepared for full fillet welding b) The pipe nozzle shall be cut to the contour of the tank and beveled to a depth of not more than 1/3 the nozzle thickness to ensure partial penetration groove welding c) The pipe nozzle shall be cut to the contour of the tank and beveled to a depth of not less than 1/3 the nozzle thickness to ensure partial penetration groove welding d) The pipe nozzle shall be cut to the contour of the tank and beveled from the outside for a full penetration weld ANS: d Q49. After the reinforcing pad is installed, the pad shall be subjected to a pneumatic test. a) True b) False ANS: a Charlie Chong/ Fion Zhang
Q50. After the valve has been installed on the flange, a pressure test of at least ______ shall be performed on the nozzle prior to mounting the hot tap machine. a) The same pressure as the pneumatic test of the reinforcing pad b) 1.25 times the hydrostatic head c) 1.5 times the hydrostatic head d) 2.0 times the hydrostatic head (to account for the added stress of the machine) ANS: c
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Answers to API-653 Section 7, Repair/Alteration
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Section 8 Dismantling & Reconstruction
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1. Bottom plates that will be reused shall be cut by de-seaming of lap-welds or by cutting alongside of the remaining welds at a minimum of _______ away from existing welds. a) One inch b) Two inches c) Four inches d) Six inches Reference API-653, Paragraph 8.3.2.1 2. Shell plates may be cut by any of the following methods except a) Shell rings ½” thick or thinner can be dismantled by cutting through the weld without removing the heat affected zone b) Cuts made a minimum of 6” away from existing welds except where cuts cross existing welds c) Cuts made a minimum of 2” away from existing welds except where cuts cross existing welds d) Any shell ring may be dismantled by cutting out existing weld seams and the heat affected zone of the weld ANS: ANS: Charlie Chong/ Fion Zhang
3. API-653 requires that new vertical joints in adjacent shell courses not be in alignment. What is the minimum offset dimension of these joints? a) Vertical joints shall be offset a minimum of 5 inches or 5t which ever is greater b) Vertical joints shall be offset a minimum of 5t where t is the plate thickness of the thicker course at the point of offset c) Vertical joints shall be offset a minimum of 5t where t is the plate thickness of the thinner course at the point of offset d) Vertical joints shall be offset a minimum of 5 inches or 5t which ever is less Reference: API-653, Paragraph 8.4.2.1 4. Roof plates shall be cut by de-seaming of lap-welds or by cutting alongside of the remaining welds at a minimum of _______ away from existing welds. a) One inch b) Two inches c) Four inches d) Six inches ANS: ANS: Charlie Chong/ Fion Zhang
5. In the reconstruction of aboveground storage tanks, welding shall be by any of the following welding processes except. a) Submerged arc welding b) Oxyfuel c) Gas metal-arc d) Forging Reference API-653, Paragraph 8.4.2.2 and API-650 5.2.1 6. No welding of any kind may be performed when the surfaces to be welded are wet from rain, snow, or ice. When rain or snow is falling or during high wind conditions, welding is permitted provided: a) The welder is secured to an anti-fall device and the work is properly grounded b) The welder has agreed to work in such conditions c) The welder and the work are properly shielded d) The owner/operator takes full responsibility for the safety of the welder and the quality of the welds ANS: ANS: Charlie Chong/ Fion Zhang
7. According to API-653, no welding is permitted when the temperature of the base metal is below what value? a) Base metal temperature below -20°F b) Base metal temperature below 0°F c) Base metal temperature below 20°F d) Base metal temperature below 30°F Reference API-653, Paragraph 8.4.2.3 8. If the base metal is greater than 1” thickness or the temperature of the base metal is between 0°F and 32°F what requirement does API-653 stipulate? a) The base metal within 3 inches of the weld area shall be heated to a temperature that is warm to the hand (approximately 180°F) b) The base metal within 8 inches of the weld area shall be heated to a temperature that is warm to the hand (approximately 140°F) c) The base metal within 3 inches of the weld area shall be heated to a temperature that is warm to the hand (approximately 140°F) d) The base metal within 8 inches of the weld area shall be heated to a temperature that is warm to the hand (approximately 180°F) Charlie Chong/ Fion Zhang
9. What is the maximum permissible undercut of the base metal for vertical joints? a) 1/64 b) 1/32 c) 1/19 d) 1/16 10. What is the maximum permissible undercut of the base metal for horizontal joints? a) 1/64 b) 1/32 c) 1/19 d) 1/16 ANS: ANS:
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11. What is the maximum weld reinforcement thickness permitted on each side of the plate for a plate, which is 7/8” thick? Vertical joints Horizontal joints a) 3/32” 1/8” b) 1/8” 3/16” c) 3/16” 1/4 d) 1/4 5/16” ANS: ANS:
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Section 8 Dismantling & Reconstruction
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Q1. Bottom plates that will be reused shall be cut by de-seaming of lap-welds or by cutting alongside of the remaining welds at a minimum of _______ away from existing welds. a) One inch b) Two inches c) Four inches d) Six inches (shell ring) ANS: b Q2. Shell plates may be cut by any of the following methods except a) Shell rings ½” thick or thinner can be dismantled by cutting through the weld without removing the heat affected zone b) Cuts made a minimum of 6” away from existing welds except where cuts cross existing welds c) Cuts made a minimum of 2” away from existing welds except where cuts cross existing welds (bottom plate) d) Any shell ring may be dismantled by cutting out existing weld seams and the heat affected zone of the weld ANS: C Charlie Chong/ Fion Zhang
AST Tanks
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AST Tanks
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Q3. API-653 requires that new vertical joints in adjacent shell courses not be in alignment. What is the minimum offset dimension of these joints? a) Vertical joints shall be offset a minimum of 5 inches or 5t which ever is greater b) Vertical joints shall be offset a minimum of 5t where t is the plate thickness of the thicker course at the point of offset c) Vertical joints shall be offset a minimum of 5t where t is the plate thickness of the thinner course at the point of offset d) Vertical joints shall be offset a minimum of 5 inches or 5t which ever is less ANS: b
10.4.2 Welding 10.4.2.1 Provisions shall be made during the reconstruction of a tank to ensure that weld spacing requirements of Figure 9.1 are maintained. New vertical joints in adjacent shell courses, made in accordance with 10.3.3.1, shall not be aligned but shall be offset from each other a minimum distance of 5t, where t is the plate thickness of the thicker course at the point of the offset. Charlie Chong/ Fion Zhang
Q4. Roof plates shall be cut by de-seaming of lap-welds or by cutting alongside of the remaining welds at a minimum of _______ away from existing welds. a) One inch b) Two inches c) Four inches d) Six inches ANS: b Comment: Shell Roof/Bottom
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6â&#x20AC;? 2â&#x20AC;?
Q5. In the reconstruction of aboveground storage tanks, welding shall be by any of the following welding processes except. a) Submerged arc welding b) Oxyfuel c) Gas metal-arc d) Forging ANS: B Q6. No welding of any kind may be performed when the surfaces to be welded are wet from rain, snow, or ice. When rain or snow is falling or during high wind conditions, welding is permitted provided: a) The welder is secured to an anti-fall device and the work is properly grounded b) The welder has agreed to work in such conditions c) The welder and the work are properly shielded d) The owner/operator takes full responsibility for the safety of the welder and the quality of the welds ANS: c
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Q7. According to API-653, no welding is permitted when the temperature of the base metal is below what value? a) Base metal temperature below -20°F b) Base metal temperature below 0°F c) Base metal temperature below 20°F d) Base metal temperature below 30°F ANS: B Q8. If the base metal is greater than 1” thickness or the temperature of the base metal is between 0°F and 32°F what requirement does API-653 stipulate? a) The base metal within 3 inches of the weld area shall be heated to a temperature that is warm to the hand (approximately 180°F) b) The base metal within 8 inches of the weld area shall be heated to a temperature that is warm to the hand (approximately 140°F) c) The base metal within 3 inches of the weld area shall be heated to a temperature that is warm to the hand (approximately 140°F) d) The base metal within 8 inches of the weld area shall be heated to a temperature that is warm to the hand (approximately 180°F) ANS: C Charlie Chong/ Fion Zhang
Q9. What is the maximum permissible undercut of the base metal for vertical joints? a) 1/64 b) 1/32 c) 1/19 d) 1/16 ANS: a Q10. What is the maximum permissible undercut of the base metal for horizontal joints? a) 1/64 b) 1/32 c) 1/19 d) 1/16 ANS: b
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Q11. What is the maximum weld reinforcement thickness permitted on each side of the plate for a plate, which is 7/8” thick? Vertical joints Horizontal joints a) 3/32” 1/8” b) 1/8” 3/16” c) 3/16” 1/4 d) 1/4 5/16” ANS: B Q12. Tack welds used in the assembly of vertical joints in tank shells may remain in place when the joints are welded manually provided: a) They are properly cleaned of all weld slag b) They are sound c) Liquid Penetrant or Magnetic Particle examination is performed d) They shall not remain ANS: d
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Q13. What are the requirements for making tack welds according API-653? a) If the tack weld is to be removed, it must be made using qualified weld procedure and qualified welder b) If the tack weld is to remain in place, it must be made using qualified weld procedure and qualified welder c) If the tack weld is to remain in place, it may be made using any weld procedure acceptable to the owner/operator d) If the tack weld is to be removed, it may be made by any welder wishing to gain experience provided the process is the SMAW process ANS: B
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Q14. All coatings must be removed from the weld area prior to welding except weldable primer coatings. What must done if these primer coatings are used? a) Weldable primer coatings must also be removed b) If the coating is applied by brush it may remain provided the application is performed to a written procedure c) They shall be included in welding procedure qualification tests for brand, formulation, and maximum thickness of primer applied d) They shall be included in welding procedure qualification tests for the method of application either by brushing or by spraying or a combination of the two. ANS: C
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Q15. When welding tank bottoms, when should the shell-to-bottom weld be completed? a) This joint (except for door sheets) can be welded as soon as the bottom plates are laid out and welded b) This joint (except for door sheets) shall be welded as soon as the first bottom weld joint is completed to prevent distortion c) This joint (except for door sheets) shall be welded as work progresses around the tank bottom d) This joint (except for door sheets) shall be completed before the welding of bottom joints ANS: D Q16. What is the maximum permissible misalignment of vertical joints in shell plates that are .9375” thick? a) .125” b) .09375” c) .009375” d) .0125” ANS: a Charlie Chong/ Fion Zhang
Q17 What is the maximum permissible misalignment of vertical joints in shell plates that are .625” thick? a) .0625” b) .00625” c) .125” d) .0125” ANS: a Vertical Weld t > 5/8 misalignment 10%t or 1/8 max t ≤5/8 misalignment ≤ 1/16 Q18. Vertical joints shall be completed before the lower horizontal weld is made. a) True b) False ANS: a
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Q19. In completing horizontal joints, what is the maximum projection of the upper plate, beyond the face of the lower plate, at any point for plate thickness of 1.125” a) .25” b) .225” c) .125” d) .0125” ANS: C Q20. When welding horizontal and vertical joints constructed of material that is over 1.5” thick, based on the thickness of the thicker part, what is the required preheat temperature? a) Preheating is not required b) 140°F c) 200°F d) 300°F ANS: c
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Q21. When shall measurements be taken to verify tolerances of reconstructed tanks? a) After hydrostatic testing b) Before hydrostatic testing c) After lay out of all plates d) After fit-up and tack welding used for alignment purposes ANS: b 10.5.1.2 Measurements to verify these tolerances shall be taken before the hydrostatic test of the reconstructed tank. Q22. What is the maximum out-of-plumbness of the top of the shell relative to the bottom of the shell of a tank with a total height of 62.25 feet? a) 7.47” b) .6225” c) 6.25” d) 5” ANS: d
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Q23. An aboveground storage tank is 115 feet in diameter. What is the maximum or minimum radius permitted measured at one foot above the shellto-bottom weld? Maximum Minimum a) 115.75” 114.25” b) 690.75” 689.25” c) 1380.75” 1379.25” d) 115.5” 114.5” ANS: c
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Q24. An aboveground reconstructed tank is 126.5 feet in diameter. What is the maximum or minimum radius permitted measured at the second shell course up from the bottom? Maximum Minimum a) 759.75” 758.25 b) 761.25” 756.75” c) 1520.25” 1515.75” d) 128.75” 124.25” ANS: c
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Radius & Diameter are not Gravitational Wave! Do make the mistake again!
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Radius & Diameter are not Gravitational Wave! Do make the mistake again!
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Radius & Diameter are not Gravitational Wave! Do make the mistake again! https://evilgenius180.wordpress.com/2012/10/13/constellation-class-v3-0-pt-13/
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Q25. Peaking shall not exceed ½”. This is measured using a horizontal sweep board of what dimensions? a) The sweep board shall be 48” long and made to the true outside radius of the tank b) The sweep board shall be 48” long and made to the true inside radius of the tank c) The sweep board shall be 36” long and made to the true outside radius of the tank d) The sweep board shall be 36” long and made to the true inside radius of the tank ANS: c Q26. Banding shall not exceed ____ with a vertical 36” long sweep board. a) One half inch b) Three quarter inch c) One inch d) One and one eighth inch ANS: c
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Q27. The top of the concrete ringwall of a reconstructed tank, that is 115 feet in diameter, must be level within ± 1/8” in any 30 feet of circumference. What is the tolerance measured from the average elevation? a) ±1/8” b) ±3/16” c) ±1/2” d) ±1/4” ANS: d
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Q28. Where concrete ringwalls are not provided, the foundation under the shell shall be level to within what tolerances? a) ±1/8” in any 30’ of the circumference and ±1/2” in the total circumference measured from the average elevation b) ±1/8” in any 10’ of the circumference and ±1/2” in the total circumference measured from the average elevation c) ±1/8” in any 10’ of the circumference and ±1/4” in the total circumference measured from the average elevation d) ±1/8” in any 30’ of the circumference and ±1/4” in the total circumference measured from the average elevation ANS: b
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Q29. For foundations specified to be sloped from a horizontal plane, the actual elevation shall not deviate from the calculated differences by more than which of the following where concrete ringwalls are provided? a) ±1/8” in any 30’ of the circumference and ±1/4” in the total circumference measured from the average elevation b) ±1/8” in any 10’ of the circumference and ±1/2” in the total circumference c) ±1/8” in any 10’ of the circumference and ±1/2” in the total circumference measured from the average elevation d) ±1/8” in any 30’ of the circumference and ±1/4” in the total circumference ANS: d
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Q30. For foundations specified to be sloped from a horizontal plane, the actual elevation shall not deviate from the calculated differences by more than which of the following where concrete ringwalls are not provided? a) ±1/8” in any 30’ of the circumference and ±1/2” in the total circumference measured from the average elevation b) ±1/8” in any 10’ of the circumference and ±1/2” in the total circumference c) ±1/8” in any 10’ of the circumference and ±1/2” in the total circumference measured from the average elevation d) ±1/8” in any 30’ of the circumference and ±1/4” in the total circumference ANS: b
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Answers to API-653 Section 8, Dismantling & Reconstruction
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Section 9 Welding
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Q1. Welding procedure specifications and welders and welding operators shall be qualified in accordance with __________. a) Original code of construction b) Owner/operatorâ&#x20AC;&#x2122;s specification c) Section IX of the ASME Code d) Repair organizationâ&#x20AC;&#x2122;s specifications ANS: c Q2. According to API Standard 653, if the material specification for the steel from an existing tank is unknown or obsolete what must be done? a) The material can not be used for tank reconstruction b) Test coupons for the WPS shall be taken from the actual plate to be used c) Test coupons for the WPS may be taken from a similar material of known specification d) Test coupons for the WPS shall only be taken from weld filler metal and not from the base metal ANS: b
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Q3. Each welder and welding operator shall be assigned ________. a) Only one joint to ensure traceabilitiy b) A specific welding machine c) An identifying number, letter, or symbol d) Weld joints on only one side of the tank ANS: c Q4. How does each welder and welding operator identify the welds produced by them? a) Each welder and welding operatorâ&#x20AC;&#x2122;s identification mark shall be hand or machine stamped adjacent to each completed weld. b) Each welder and welding operator shall inform the owner/operator which welds he or she completed c) Each welder and welding operator shall show the inspector exactly which welds they completed d) Each welder and welding operator shall inform the owner/operator which welds they will be making prior to the start of such welding ANS: a
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Q5. At what intervals must the welder and welding operatorâ&#x20AC;&#x2122;s identification be stamped adjacent to the completed welds? a) Identification shall be at intervals not to exceed 9 feet b) Identification shall be at intervals not to exceed 7.5 feet c) Identification shall be at intervals not to exceed 6 feet d) Identification shall be at intervals not to exceed 3 feet ANS: d Q6. In lieu of stamping, a record may be kept that identifies the welder or welding operator for each welded joint. a) True b) False ANS: a
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Q7. What welds do not require welderâ&#x20AC;&#x2122;s identification? a) All welds require identification b) Vertical welded joints which are located within the final shell course since this course will be subjected to relatively low stresses c) Roof plate welds and flange-to-nozzle-neck welds d) Roof plate welds and bottom plate welds ANS: c
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Answers to API-653 Section 9, Welding
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Section 10 Examination & Testing
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Q1. Nondestructive examination procedures, qualifications, and acceptance criteria is required for VT, MT, UT, PT, and RT methods and must be in accordance with what Code or Standard? a) ASME Code Section V, Nondestructive examination b) API Standard 650 only c) API Standard 650 and the supplements given in API-653 d) Owner/operatorâ&#x20AC;&#x2122;s specifications ANS: c Q2. Personnel performing nondestructive examination shall be qualified in accordance with _____. a) API Standard 650 and the supplemental requirements of API-653 b) ASME Code Section V, Nondestructive Examination c) SNT-TC-1A d) The owner/operatorâ&#x20AC;&#x2122;s specifications ANS: a
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Q3. When it is necessary to install a hot tap connection or add a reinforcing plate to an existing un-reinforced penetration, API 653 requires what type, extent, and purpose of examination. a) Magnetic particle examination for slight sub-surface discontinuities shall be performed in an area equal to twice the diameter of the opening b) Radiographic examination for cracking shall be performed in the immediate area c) Ultrasonic examination for cracking shall be performed in the immediate area d) Ultrasonic examination for lamination shall be performed in the immediate area ANS: d 4. Completed welds attaching nozzle neck to shell, and reinforcing plate to shell and nozzle neck, shall be examined by _______. a) Ultrasonic or Radiography b) Magnetic Particle or Liquid Penetrant c) Visual examination or Liquid Penetrant d) Ultrasonic or Magnetic Particle ANS: b Charlie Chong/ Fion Zhang
Q5. How and when does API Standard 653 require the examination of welds of completed stress relieved assemblies? a) Completed welds of stress relieved assemblies shall be examined visually only after stress relief and hydrostatic test b) Completed welds of stress relieved assemblies shall be examined visually as well as by ultrasonic methods after stress relief but before hydrostatic test c) Completed welds of stress relieved assemblies shall be examined visually as well as by magnetic particle or liquid penetrant methods after stress relief but before hydrostatic test d) Completed welds of stress relieved assemblies shall be examined visually or by radiography after stress relief but before hydrostatic test ANS: c 12.1.2.4 Completed welds of stress-relieved assemblies shall be examined by the magnetic particle or liquid penetrant methods after stress relief, but before hydrostatic testing.
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Q6. Completed butt welds between insert plates and the shell require what type and extent of examination? a) Complete radiography b) Spot Radiography c) Random Radiography d) Random Spot Radiography ANS: a 12.2.1.8 For penetrations installed using insert plates as described in 9.8.6, the completed butt welds between the insert plate and the shell plate shall be fully radiographed.
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Q7. In repairing butt weld flaws, what type and extent of examination is required by API-653? a) Random examination by radiography or ultrasonic methods of the full length of repair b) Examined full length of the repair by liquid penetrant or magnetic particle methods c) Examined at three foot intervals by radiography or ultrasonic methods d) Examined full length of the repair by radiography or ultrasonic methods ANS: d Q8. Completed repairs of fillet welds shall be examined over their full length by the appropriate nondestructive method listed in API-653. a) True b) False ANS: a
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Q9. With regards to new welds attaching shell plate to shell plate, what method(s) of examination is/are required on the completed weld? a) Visual b) Visual and Radiography c) Visual and magnetic particle or liquid penetrant d) Visual and ultrasonic ANS: b Q10. With regards to new welds attaching shell plate to shell plate for plate thickness greater than one inch, what additional extent and method of examination is required by API-653? a) The back gouged surface of the root and final pass (each side) shall be examined for its complete length by the Inspector b) The back gouged surface of the root and final pass (each side) shall be examined for its complete length visually c) The back gouged surface of the root and final pass (each side) shall be examined for its complete length by magnetic particle or liquid penetrant d) The back gouged surface of the root and final pass (each side) shall be examined for its complete length by ultrasonic ANS: c Charlie Chong/ Fion Zhang
Q11. New welding on the shell-to-bottom joint shall be inspected for its entire length by _____ and _______ or ________. a) Visual examination, liquid penetrant , magnetic particle b) Right-angle vacuum box and solution film, light diesel oil c) Visual examination, ultrasonic, eddy current d) Visual examination, wet fluorescent magnetic particle, helium tracer gas ANS: a Q12. In applying light diesel oil to the opposite side of the first pass of new shell-to-bottom joints, how long must the oil remain on the weld and what is the weld inspected for? a) The oil shall be allowed to stand at least four hours and the weld inspected for wicking action b) The oil shall be allowed to stand at least three hours and the weld inspected for wicking action c) The oil shall be allowed to stand at least two hours and the weld inspected for wicking action d) The oil shall be allowed to stand at least one hour and the weld inspected for wicking action ANS: a
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Q13. The existing weld at the shell-to-bottom joint shall be examined visually and magnetic particle or liquid penetrant methods, for the full length under a welded-on patch plate. How much additional shell-to-bottom joint must be examined? a) Three inches on each side of the patch plate b) Six inches on each side of the patch plate c) nine inches on each side of the patch plate d) twelve inches on each side of the patch plate ANS: d Q14. How and to what extent are newly welded bottom joints tested? a) Newly welded bottom joints shall be tested their entire length using liquid penetrant b) Newly welded bottom joints shall be tested their entire length using a vacuum box and a solution film, or a tracer gas and detector c) Newly welded bottom joints shall be tested their entire length using visual and ultrasonic examination d) Newly welded bottom joints shall be tested their entire length using wet fluorescent magnetic particle examination ANS: b Charlie Chong/ Fion Zhang
Q15. What are the requirements, regarding examination, of a welded-on patch plate in the critical zone? a) The final weld shall be examined by radiography over its entire length b) Root and final pass shall be examined by radiography over its entire length c) The root and final pass shall be examined visually over its entire length d) The root and final pass shall be examined visually and by magnetic particle of liquid penetrant method over its entire length ANS: d Q16. API-653 requires the number and location of radiographs to in accordance with API-650. In addition, API-653 requires how many and what location for new or repaired shell vertical joints? a) For new or repaired shell vertical joints one radiograph shall be taken in each fifty foot length b) For new or repaired shell vertical joints one radiograph shall be taken in each twenty-five foot length c) For new or repaired shell vertical joints one radiograph shall be taken in every joint d) For new or repaired shell vertical joints one radiograph shall be taken in every other joint
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Q15. What are the requirements, regarding examination, of a welded-on patch plate in the critical zone? a) The final weld shall be examined by radiography over its entire length b) Root and final pass shall be examined by radiography over its entire length c) The root and final pass shall be examined visually over its entire length d) The root and final pass shall be examined visually and by magnetic particle of liquid penetrant method over its entire length ANS: d Q16. API-653 requires the number and location of radiographs to in accordance with API-650. In addition, API-653 requires how many and what location for new or repaired shell vertical joints? a) For new or repaired shell vertical joints one radiograph shall be taken in each fifty foot length b) For new or repaired shell vertical joints one radiograph shall be taken in each twenty-five foot length c) For new or repaired shell vertical joints one radiograph shall be taken in every joint d) For new or repaired shell vertical joints one radiograph shall be taken in every other joint
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Q17. API-653 requires the number and location of radiographs to in accordance with API-650. In addition, API-653 requires how many and what location for new or repaired shell horizontal joints? a) For new or repaired shell horizontal joints one radiograph shall be taken in each twenty-five feet of horizontal joint including those required at intersections of vertical and horizontal joints b) For new or repaired shell horizontal joints one radiograph shall be taken in each twenty-five feet of horizontal joint not including those required at intersections of vertical and horizontal joints c) For new or repaired shell horizontal joints one radiograph shall be taken in each fifty feet of horizontal joint including those required at intersections of vertical and horizontal joints d) For new or repaired shell horizontal joints one radiograph shall be taken in each fifty feet of horizontal joint not including those required at intersections of vertical and horizontal joints ANS: d
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Q18. API-653 requires two radiographs to be taken at each new or replacement intersection between vertical and horizontal joints. One to comply with the requirement for vertical joints and one to comply with the requirements for horizontal joints. a) True b) False ANS: b Q19. For reconstructed tanks, each butt-welded annular plate joint shall be radiographed in accordance with which of the following? a) API-650 b) ASME - Section V c) API-653 and API-575 d) Owner/operator's specifications ANS: a
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Q20. For reconstructed tanks, radiographic examination is required for what percentage of all junctions of new welds over existing seams? a) 100% b) 75% c) 50% d) 25% ANS: a Q21. Radiographic examination is required for new and replaced shell insert plate and door shell welds. What are the minimum number and location of such radiographs? a) Circular plates - four radiographs are required, one at each quadrant b) Square or rectangular - two radiographs are required in each vertical joint and one in a horizontal joint c) Circular plates - one radiograph and for square or rectangular - one in a vertical joint, one in a horizontal joint, and one in each corner d) Circular and square of rectangular new or replaced insert plates require 100% examination ANS: c Charlie Chong/ Fion Zhang
Q22. What is the minimum diagnostic length of each radiograph? a) The minimum diagnostic length of each radiograph shall be six inches b) The minimum diagnostic length of each radiograph shall be three inches c) The minimum diagnostic length of each radiograph shall be nine inches d) The minimum diagnostic length of each radiograph shall be twelve inches ANS: a Q23. If the radiograph of an intersection between a new and old weld discloses discontinuities, which are unacceptable by current standards, what must be done? a) The unacceptable welds must be removed and made in accordance with current standards b) The unacceptable welds shall be repaired to bring them in to compliance c) The existing welds may be evaluated according to the original standard of construction d) The existing welds shall be evaluated using the acceptance criteria of ASME Section VIII ANS: c
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Q24. Radiographs and radiograph records of all repaired welds shall be marked with what letter(s)? a) "RW" (Repaired Weld) b) "WR" (Weld Repair) c) "A" (Accepted repair) d) "R" ANS: d Q25. Hydrostatic testing is required for reconstructed tanks and tanks that have undergone major repairs or alterations. What is the minimum length of time the hydrostatic test must be held? a) The time is up to the discretion of the Inspector b) Twenty-four hours c) The time is up to the discretion of the owner/operator d) Twelve hours ANS: b
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Q26. Major repair and major alteration is defined by API-653 by which of the following? a) Cutting, addition, removal and/or replacement of the annular plate ring only if the plate is less than 1/2" thick b) Cutting, addition, removal an/or replacement of the annular plate ring, the shell-to-bottom weld, or a sizeable portion of the shell c) Cutting, addition, removal an/or replacement of the annular plate ring, the shell-to-bottom weld, or a 100 square inch portion of the shell d) Cutting, addition, removal an/or replacement of the annular plate ring, the shell-to-bottom weld, or a sizeable portion of the shell in shell material greater than 3/4" thick ANS: b Q27. Of the following, which would not be considered a major repair or alteration? a) The installation of a shell penetration NPS 12 above the design liquid level b) The installation of a shell penetration NPS 12 below the design liquid level c) Jacking of a tank shell d) The complete of partial removal and replacement of more than 12
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Q28. A full hydrostatic test of the tank is not required for major repairs and alterations when certain conditions are met. Where would you look for these conditions? a) API-650 Paragraph 5.3.6 b) API-RP-575 Paragraph 7.5 c) API-510 Paragraph 6.4 d) API-653 Paragraph 10.3.2 ANS: d Q29. Hydrostatic testing is not required for shell repairs when all but which of the following are complied with? a) Impact test requirements shall follow appropriate portions of API-650 and must be specified in the repair procedure b) New vertical and horizontal shell butt-welds must have complete penetration and fusion c) New materials shall meet the current edition of ASME Section II Part A d) Finished weld must be examined by radiography ANS: c
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Q30. If the owner/operator elects to utilize a fitness-for-service evaluation to exempt a repair form hydrostatic testing, who perform the evaluation? a) Fitness-for-service evaluations may not be used to exempt hydrostatic testing following a repair b) The Authorized Inspector c) Engineer experienced in storage tank design and the evaluation methods used d) Exemption of hydrostatic testing for repairs can only be given by the jurisdiction ANS: c Q31. When settlement is anticipated, a tank that is to be hydrostatically tested shall: a) Have the plumbness checked b) Have the water tested to ensure it is potable c) Have the perimeter dike system checked d) Have the foundation checked for settlement ANS: d
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Q32. The tank settlement shall initially be surveyed with the tank empty. What is the minimum number of settlement measurement points for a tank which is 110 feet in diameter? a) Minimum number of settlement points is 11 b) Minimum number of settlement points is 32 c) Minimum number of settlement points is 8 d) Minimum number of settlement points is 12 ANS: d Q33. The tank settlement shall initially be surveyed with the tank empty. What is the minimum number of settlement measurement points for a tank which is 60 feet in diameter? a) Minimum number of settlement points is 12 b) Minimum number of settlement points is 6 c) Minimum number of settlement points is 8 d) Minimum number of settlement points is 4 ANS: c
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Q34. Regardless of the minimum number of settlement measurement points required, what is the maximum spacing between settlement measurement points? a) 24 feet b) 32 feet c) 36 feet d) 40 feet ANS: b Q35. When shall settlement be measured? a) Settlement shall be measured after the water reaches 100% of test level and again when the tank is emptied b) Settlement shall be measured during filling and when the water reaches 80% of test level c) Settlement shall be measured during filling and when the water reaches 100% of test level d) Settlement shall be measured during filling and when the water reaches 100% of test level and during emptying of the tank ANS: d Charlie Chong/ Fion Zhang
12.5.3 Settlement Survey During Hydrostatic Testing When a settlement survey is required in accordance with 12.5.1, tank settlement shall be measured during filling and when the test water reaches 100 % of the test level. 12.5.2 The minimum number of elevation points shall be as indicated by the following equation: N = D/10 where D is the tank diameter, in feet (ft). And N is the minimum required number of settlement measurement points, but no less than eight. All values of N shall be rounded to the next higher even whole number. The maximum spacing between settlement measurement points shall be 32 ft.
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Answers to API-653 Section 10, Examination and Testing
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Section 11 Marking
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Q1. Tanks that are reconstructed, in accordance with API-653 shall be identified by a corrosion-resistant metal nameplate. What is the size requirement for the letters and numerals to be used on this nameplate and how are they applied to the nameplate? a) Letters and numerals not less than 1/2" high shall be embossed, engraved, or stamped in the plate b) Letters and numerals not less than 1/4" high shall be embossed, engraved, or stamped in the plate c) Letters and numerals not less than 5/32" high shall be painted on the plate or embossed, engraved, or stamped in the plate d) Letters and numerals not less than 5/32" high shall be embossed, engraved, or stamped in the plate ANS: d
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Q2. Where should the new nameplate be attached and what should be done with the existing nameplate a) The new nameplate shall be attached to the tank shell adjacent to the existing nameplate. The existing nameplate shall be cleaned or suitably reconditioned b) The new nameplate shall be attached to the tank shell adjacent to the existing nameplate. The existing nameplate shall be left attached to the tank c) The new nameplate shall be attached to the tank shell adjacent to the existing nameplate. The existing nameplate shall be removed and placed in the tank record file d) The new nameplate shall be attached to the tank shell adjacent to the existing nameplate. The existing nameplate shall then be discarded ANS: b
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Q3. All but which of the following information shall be made part of the owner/operator's records for aboveground storage tanks? a) Names of all operators of the tank b) Calculations c) Construction and repair drawings d) Additional supporting data ANS: a
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Answers to API-653 Section 11, Marking
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Section 12 Appendix B â&#x20AC;&#x201C; Evaluation of Tank Bottom Settlement
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Q1. External measurements for tank settlement shall be taken at points having a maximum spacing of ____ around the circumference. a) 24 feet b) 28 feet c) 32 feet d) 36 feet ANS: c Q2. Regardless of tank size, what is the minimum number of settlement point measurements? a) Four b) Eight c) Twelve d) Based on the formula 10 ANS: b
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Q3. Internal measurement for tank bottom settlement taken across the diameter of the tank must be taken at what maximum spacing? a) 10 feet b) 24 feet c) 32 feet d) 4 feet ANS: a Q4. Which of the following is not listed as settlement component? a) Uniform settlement b) Rigid body tilting of a tank (planar tilt) c) Out-of-plane settlement (differential settlement) d) Soil undermining (total tank sinking) ANS: d
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Q5. What type of settlement is depicted here? ă&#x20AC;&#x20AC; a) Bottom settlement near tank shell b) Edge settlement c) Localized bottom remote from tank shell d) Planar settlement ANS: b
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Q6. Using the formula in B-3.2, determine the maximum permissible deflection (out of plane distortion) for a tank with the following data reported. Diameter 110 feet Height 60 feet Material Carbon Steel (Young's modulus = 29,000,000 psi) Yield strength 30,000psi Arc length 31.4 feet between measurements a) S = .09 feet b) S = .9 feet c) S = 9 feet d) S = .009 feet ANS: Smax = 31.4x31.4x30000x11/ (2x29000000x60) = a
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Q7. What is the maximum depth of a local depression in a tank bottom if the radius of an inscribed circle is equal to 7.5 feet? a) BB = .2775 inches b) BB = 2.775 inches c) BB = 27.75 inches d) BB = .02775 inches ANS: BB = 0.37R = B
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Answers to API-653 Appendix B, Tank Bottom Settlement
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Good Luck!
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Good Luck!
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