EWN Bulletin by RMC Process Controls & Filtration, LLC.

Bulletin 51.1:EWN

June 1981

EWN Series Control Valve Bodies The EWN Series valve bodies are available only with Whisper Trim III cages (figures 1, 2, and 3) and are used on compressible fluid (including sour gas) applications requiring maximum noise attenuation capability coupled with high capacity. As members of the versatible easy-e family of industrial control valves, these bodies share with other easy-e bodies the following characteristics: single ports, multiple trim material choices, and the interchangeability of trim parts that permits reconfiguring the body to a different design variation.

Features D Noise Attenuation—A Whisper Trim III cage used in an EWN Series valve body can reduce noise produced by high flow rates and large pressure drops up to 30 decibels below the normal valve noise level. D Piping Economy—Expanded end connections of EWN Series bodies reduce the need for line swages while accommodating oversized piping arrangements used to limit fluid flow velocities.

D Full Rated Inlet Pressure Capability—Design of standard body-to-bonnet bolting allows inlet pressures equal to full rating: no derating required.

Available Configurations All body designs covered in this bulletin have single ports, balanced push-down-to-close valve plugs, a choice of eight different Whisper Trim III cage levels (A1, A3, B1, B3, C1, C3, D1, or D3), and metal-tometal seating. In this series, the EW designates expanded end connections, and the N designates an extended upper body cavity that permits full utilization of a long-travel cage without requiring a bonnet spacer. This body is combined with different plug

W3310/IL

Figure 1. 12 x 8 In. Design EWNT-2 Body with Type 470-16 Actuator

styles and either a seat ring threaded into the body (–1 suffix) or a seat ring threaded into the cage (–2 suffix) to result in the following configurations: Design EWND-1: EWN Series body with graphite piston ring(s) on valve plug (see table 2) and with seat ring threaded into body (figure 2), for all general applications over a wide range of pressure drops and temperatures. Design EWNT-1: EWN Series body (Class 900 only) with spring-loaded seal ring on valve plug and with seat ring threaded into body (figure 2), for more stringent shutoff requirements up to 450°F (232°C).

D100024X012

D Temperature Compensation—The hanging cage design (figure 2 or 3) reduces gasketing problems caused by thermal expansion and contraction of long parts such as the cage assembly.

Bulletin 51.1:EWN Specifications Whisper Trim Flow Characteristic

Body Sizes See table 1 End Connection Styles Flanged Ends: Styles per ANSI B16.5-1977 are Class 300, 600, or 900 J raised-face or J ring-type joint Buttwelding Ends: Standard styles per ANSI B16.25-1972 are Schedule J 40 or J 80 for all Class 300 and 600 valves or Schedule J 80, J 100, or J 120 for all Class 900 valves; optional styles are available Maximum Inlet Pressures and

Temperatures(1)

Consistent with applicable Class J 300, J 600, or J 900 pressure-temperature ratings per ANSI B16.34-1977, unless limited by the individual pressure/temperature capabilities in figure 4, 5, or 6 or temperature capabilities in table 4 Maximum Pressure Drop(1) Same as maximum inlet pressure for specific construction defined above, except where further limited by the following max ∆P/P1, ratio, –0.60 for level A cage, 0.75 for level B cage, 0.85 for level C cage, or 0.99 for level D cage(2) Shutoff Classifications See table 2 Construction Materials Body and Bonnet: J WCB steel, J WC6 or J WC9 chrome moly steel, or J 316 SST (CF8M) Trim Parts: See table 3 Other Parts: See table 4 Material Temperature Capabilities(1) Body-Trim Combinations: See figure 4, 5, or 6 Other Parts: See table 4 1. The pressure/temperature limits in this bulletin and any applicable standard limitation should not be exceeded.

Design EWNT-2: Similar to Design EWNT-1 body but with spring-loaded seal rings on both seat ring and valve plug and with seat ring threaded into cage (figure 3).

Material Selection Guidelines 1. Select the body/bonnet material from the specifications table and the shutoff classification from table 2,

8 x 6 In. Body Cage Level A, B, or C: Linear Cage Level D: Equal percentage for first 1-1/2 in. (38.1 mm) of travel, then linear 12 x 8 In. Body: Linear

Whisper Trim Flow Direction Up through the valve body seat ring and out through the cage (figure 3) Flow Coefficients and Noise Level Prediction See Fisher Catalog 10 Port Diameters and Valve Plug Travels See table 1 Yoke Boss and Stem Diameters See table 5 Typical Bonnet Styles Plain: Available with all bodies Style 1 Extension: Available with Class 300 or 600 bodies Approximate Weights See figure 7 Options J Lubricator J lubricator/isolating valve J drilled

and tapped connection in extension bonnet for leakoff service J body drain plug J style 3 fabricated extension bonnet made on order to a specific length for cryogenic service J packings suitable for nuclear service J body and bonnet in castable alloys other than those given in the construction materials specification, and J forged bonnet for 5 in. (127 mm) yoke boss on Class 900 8 x 6 in. body 2. Limitation based on excessive noise if max ∆P/P1 ratio for a given cage level is exceeded.

keeping in mind that the valve service conditions cannot exceed the ANSI pressure/temperature limitations for the selected body. 2. Choose a trim combination for the service conditions according to figure 4, 5, or 6, while making sure from table 3 that this combination provides the desired trim materials. 3. Finally, check in table 4 that packing and other valve parts also are available in materials that meet the desired service conditions.

Bulletin 51.1:EWN

VALVE PLUG SEAL RING

SEAT RING SEAL RING

DOUBLE PISTON RINGS

LUGS FOR UNSCREWING SEAT RING FROM BODY

W3317*/IL

W3290*

RETAINING RING

Figure 3. 12 x 8 In. Design EWNT-2 Body with Seat Ring Threaded into Cage

SEAL RING BACKUP RING

Table 1. Body Sizes, Valve Plug Travels, and Port Diameters BODY DESIGN

BODY SIZE, IN. (END CONN. SIZE x TRIM SIZE) 8x6

W3316*/IL

EWND-1 EWND 1

12 x 8 8x6

EWNT-1 EWNT 1

EWNT-2

RATING CLASS

PORT DIAMETER

In.

900

5(1)

127(1)

5-3/8

136

300, 600, or 900

203

7-3/4 (2)

197(2)

6-3/4 (3)

172(3)

900

5(1)

127(1)

5-3/8

136

7-3/4 (2)

197(2)

6-3/4 (3)

172(3)

7-3/4 (2)

197(2)

6-3/4 (3)

172(3)

12 x 8

900

12 x 8

300 or 600

Figure 2. Constructions with Seat Ring Threaded into Body

VALVE PLUG TRAVEL

8 8

203 203

1. Restricted to 4-1/2 in. (114 mm) with 3 piston rings for optional Class IV shutoff. 2. Level A, B, or C cages. 3. Level D cages.

Bulletin 51.1:EWN Table 2. Shutoff Classifications per ANSI B16.104-1976 Shutoff Class

Body Design

EWND-1

EWNT-1 or EWNT-2

Max Leakage(1)

III (standard for 8 x 6 in. body with 2 piston rings and 12 x 8 in. body with 3 piston rings) IV (optional for 8 x 6 in. body with 3 piston rings and restricted travel, and for 12 x 8 in. body with 2 piston rings and full travel) IV

Fisher Test Fluid

0.1% of valve capacity at full travel

0.01% of valve capacity at full travel

Air at service ∆P or 50 psi (3.4 bar) drop, whichever is lower, and between 50 and 125°F (10 and 52°C)

0.01% of valve capacity at full travel

1. Based on capacity obtained with level A cage.

Table 3. Metal Trim Part Combinations (1) Trim Designation

Valve Plug

Cage

Baffle (for Level D Cages Only)

Seat Ring

I (available only in 12 x 8 in. body size)

CA6NM(2)

17-4PH SST with H1025 heattreat condition

Steel

316 SST with seat and guide hard-faced with Alloy 6(3)

17-4PH SST with H1025 heattreat condition

Steel(4)

III (available only in 8 x 6 in. body size)

416 SST

17-4PH SST with H1025 heattreat condition

Steel