Manual

ManualsBrandsCashco ManualsAccessories for water988-MB

I. DESCRIPTION AND SCOPE

Model 988’s and 989’s are pneumatically actuated, globe-

style control valves. Sizes are 3/4", 1", 1-1/2" and 2". Ma-

te ri als are available in cast carbon steel, Grade WCB (CS);

cast 316L SST, Grade CF3M (SST); and cast CW-12MW,

sim i lar to Hastelloy C (H-C).

Failure position is determined by actuator for:

"D" = Direct action; on increasing air loading pressure, the

actuator stem extends. Fail-safe position is with the stem

retracted.

"R" = Reverse action; on increasing air loading pressure, the

actuator stem retracts. Fail-safe position is with the stem

extended.

These valves are designed for chemical service and most

com mon liquid, gaseous, or steam services.

Models 988 and 989 differ only in the face-to-face di men -

sions of ﬂ anged units; 988’s have a “regular” (“long”) body

pattern, and the 989’s have a “short” body pattern.

INSTALLATION, OPERATION & MAIN TE NANCE MANUAL (IOM)

IOM-988/989

12-13

MODELS 988 and 989

GLOBE-STYLE PNEUMATIC CONTROL VALVE BODY

SECTION I

SECTION II

II. REFERENCE

Refer to Technical Bulletin 988-TB or 989-TB for complete

tech ni cal speciﬁ cations coupled with either Cashco Actuator

Model C27 or C53.

www.cashco.com/techbulletins/988.pdf

www.cashco.com/techbulletins/989.pdf

Refer to following Installation, Operation & Main te nance

Manuals (IOM’s) for either actuator and/or devices that

maybe mounted to a Model 988 or 989:

Actuators: www.cashco.com/IOM/C27-C53.pdf

Positioners:

P/P: www.cashco.com/techbulletins/9540l.pdf

I/P: www.cashco.com/techbulletins/srd991.pdf

I/P: www.cashco.com/iom/PS2iom.pdf

ABBREVIATIONS

ATO-FC ............. Air-to-Open, Fail Closed

ATC-FO ............. Air-to-Close, Fail Open

CCW .................. Counter Clockwise

CW ..................... Clockwise

D or DIR ............. Direct Acting

HC ..................... Cast CW-12MW or Wrought Hast C-22

IAS ..................... Instrument Air Supply

LOAD ................. Positioner Output Air Pressure

R or REV ........... Reverse Acting

SIG .................... Output Signal from Instrument

SST.................... Cast or Wrought 316L Stainless Steel

V ........................ Vent

Model 988

with ATC - FO Actuator

Shown with Internal Live-Loaded Packing

Summary of content (20 pages)

PAGE 1
INSTALLATION, OPERATION & MAINTENANCE MANUAL (IOM) IOM-988/989 12-13 MODELS 988 and 989 GLOBE-STYLE PNEUMATIC CONTROL VALVE BODY SECTION I I. DESCRIPTION AND SCOPE Model 988’s and 989’s are pneumatically actuated, globestyle control valves. Sizes are 3/4", 1", 1-1/2" and 2". Materials are available in cast carbon steel, Grade WCB (CS); cast 316L SST, Grade CF3M (SST); and cast CW-12MW, similar to Hastelloy C (H-C).
PAGE 2
SECTION III III. INSTALLATION A. Orientation: 1. 2. 3. B. 3. 2 Recommended Maximum Flange Bolting Torque (ft-lbs.) Recommended orientation when installed in a horizontal pipeline is with the stem vertical. Valves may also be installed in vertical pipelines with stems horizontal. Outdoors, all installations may be oriented any angle from horizontal-to-vertical. (Orient actuator vent cap, if supplied, to not collect rainwater that might freeze.
PAGE 3
C. Removal From Piping System: 1. Care should be taken in removal of separable flanged units. Run wire in 180° crossing pattern through bolt holes to prevent flanges from coming loose during handling. CAUTION Exhibit care in handling flanged units to prevent separable flanges from coming loose, falling to floor and smashing feet/toes. Figure 2: Body Insulation SECTION IV IV. STARTUP A. General: CAUTION 1.
PAGE 4
SECTION V B. WARNING SYSTEM UNDER PRESSURE. Prior to performing any maintenance, isolate the valve/actuator from the system and relieve all pressure. Failure to do so could result in personal injury. Actuator Assembly Removal: 1. Refer to the correct actuator IOM for this procedure. 2. Secure the (BA) in a vise with the (AA) oriented vertically. 3. Rig (AA) to be supported above the (BA). Place matchmarks between the bonnet/yoke and yoke/ accessory plate. 4.
PAGE 5
c. Step B. Support the (AA) from above. Fully loosen yoke nut (25) to removal. Lift the (AA) upwards approximately 1/4"–3/8" (6–8 mm). Again, rotate plug/stem (3) CW (viewed from above) until disengagement from actuator stem (6). Record number of plug/ stem revolutions for Step B in box on previous page. NOTE: Take notice of the parts “dangling loosely” about the stem, the order of their location and their proper orientation. d. Fully raise (AA) above (BA).
PAGE 6
D. Trim and Packing Removal and Replacement for Units with Internal Live-Loaded Packing; Opt-STD or Opt-KRI: (See pg. 19 for Item # identification.) 1. Remove (AA) as described in Sub-Section V.B. Leave (BA) in vise with plug/stem (3) upwards. 2. Continue to loosen stem packing (6) by rotating packing nuts (15) CCW to just short of disengagement from packing studs (14). DO NOT REMOVE PACKING NUTS (15). 3. Remove all bonnet stud nuts (17). 4.
PAGE 7
26. 27. With the cage (10) oriented correctly on the stem assembly (3), set plug head down into the seat ring (11). Keep firm hold of the plug/stem with one hand; use other hand to push cage down into proper alignment. Lift bonnet (2) over threaded end of plug/stem (3) and carefully lower bonnet down over stem, ensuring that the critical finish zone of the bonnet’s stuffing box is not scratched by the stem’s threads.
PAGE 8
15. Solvent clean all parts to be reused including bonnet (2). Examine all parts for wear and corrosion. Replace any corroded or worn parts. Belleville spring washers (41), studs (14,16), nuts (15,17) and retainers (39) should be replaced in sets. 16. Examine plug/stem (3) at lower guide bushing area (8) for wear. If there are signs of excess wear, guide bushing should be replaced: a. Place the bonnet (2) on a bench press. Press the guide bushing (8) out of the bonnet and discard. b.
PAGE 9
22. Examine gaskets (12,13) to see if leakage occurred. Remove and discard both gaskets. Always use new gaskets upon reassembly. 23. Remove body (1) from vise. Solvent clean all loose parts with suitable solvent. Determine parts to be replaced due to wear and/or corrosion. Clean seat ring (11), cage (10), and seat retainer (23). 24. Place body (1) into vise with body/bonnet flange up. Install a new seat ring gasket (13) inside body 25.
PAGE 10
f. Wrench-tighten the packing stud nuts (15) evenly and in 1/2 revolution increments until the “upper groove on the packing follower (5), identified as “Line A” (Fig. 4), is flush with the top edge of the bonnet’s (2) stuffing box. g. Remove the packing nuts (15), lower retainers (39) and packing follower (5). h. Carefully place the upper braided ring (6.4) over the plug/stem’s (3) end and push into the stuffing box similar to the lower braided ring (6.4).
PAGE 11
b. 11. Solvent clean all parts to be reused, including bonnet. Examine any parts for wear and corrosion. Replace any corroded or worn parts. Discard old packing. 12 Examine plug/stem (3) at lower guide bushing (8) area for wear. If there are signs of excess wear, guide bushing should be replaced: a. Place the bonnet (2) on a bench press. Press guide bushing out of bonnet and discard. b. Rotate bonnet end-for-end. Place a new guide bushing into position and press fully into the bonnet. c.
PAGE 12
19. Remove body (1) from vise. Solvent clean all loose parts with suitable solvent. Determine parts to be replaced due to wear and/or corrosion. Clean seat ring (11), cage (10), and seat retainer (23) as required. d. 20. Place body (1) back into vise with body/bonnet flange up. 21. Place a new seat ring gasket (13) into position. 22. Note correct orientation of seat ring (11) and place inside the body (1). 23.
PAGE 13
Figure 11: Dimensionals for Proper Packing Load b. G. External Live-Loaded Packing Adjustment: 1. There are two types of indicators for determining “packing wear” – a. Ability to “freely spin” the spacer rings (40). b. Measure the spacing between the upper retainers (39) spacer rings (40) (see Fig. 11). NOTE: Regardless of live loaded packing design, all use the same method for obtaining the proper pre-load to new or used packing. 2.
PAGE 14
4. Slowly pressurize the actuator to a pressure equal to the lower pressure level of the bench setting; i.e. for a 5-15 psig (.34 -1.0 Barg) range, set pressure at 5 psig (.34 Barg). Take note of pressure reading when the stem first begins to move. 5. If the loading pressure for the start of stem movement is below the lower end of the desired bench setting, then the combined stem (3, 6) length is too short. a. Rotate both jam nuts (52) down to base of threads on stem (3) and tighten together. b.
PAGE 15
c. Rotate lower jam nut CCW to shorten the combined stem length. DO NOT allow actuator stem (6) to rotate in the actuator. d. Rotate upper jam nut CW to hold indicating washer (51) up against stem (6). e. Release all pressure from the actuator and repeat Step 4 previous. 6. If the loading pressure when the stem movement stops is above the upper end of the desired bench setting, then the combined stem (3, 6) length is too short. a.
PAGE 16
SECTION VII VII. TROUBLE SHOOTING GUIDE 1. Valve is “jumpy” in stroking. Possible Cause Remedy A. Excess packing friction. A1. A2. A3. A4. Realign body–stem–actuator. Packing follower too tight for optional packing designs. Install positioner. Increase bench set by changing to stiffer actuator range spring. Will require positioner if not installed. May require different airset. B. Installed backwards. B. Install per flow arrow. 2. Valve makes “screeching” noise. Possible Cause A.
PAGE 17
4. Valve exhibits “excess” seat leakage. Possible Cause D. Excess wear. Remedy D1. D5. Oversized valve operating too close to seat; go to reduced trim. Incorporate stellite trim. Remove particulate. Possible excess cavitation in liquid service. Change operation parameters. Re-lap plug–seat surface. D2. D3. D4. E. Misalignment. E. Realign body–stem–actuator. F. Composition seat failure. F1. F2. Replace soft seat. Remove “dirty” portion of fluid causing failure. G. Seat ring gasket failure.
PAGE 18
SECTION VIII VIII. ORDERING INFORMATION NEW REPLACEMENT UNIT vs PARTS "KIT" FOR FIELD REPAIR To obtain a quotation or place an order, please retrieve the Serial Number and Product Code that was stamped on the metal name plate and attached to the unit. This information can also be found on the Bill of Material ("BOM"), a parts list that was provided when unit was originally shipped. (Serial Number typically 6 digits).
PAGE 19
Composition Soft Seated Design MODEL 988/989 BODY ASSEMBLY (BA) Internal Live Loaded Packing — Metal Seated Design ITEM NO. 1 2 3 4 5 6 7 8 9 10 11 12 DESCRIPTION Body Bonnet Plug & Stem Assembly Packing Flange Packing Follower Packing Packing Washer Guide Bushing Packing Spacer Cage Seat Ring (Metal or Soft Seat) Bonnet Gasket IOM-988/989-BODY ITEM NO. 13 14 15 16 17 19 20 21 22 23 DESCRIPTION ITEM NO. DESCRIPTION Gasket (Seat Ring) 24 Seat Insert (Soft Seat) Stud (Packing Flange) 25 Yoke Nut Hex.
PAGE 20
MODEL 988/989 BODY ASSEMBLY (BA) External Live Loaded Packing — Metal Seated Design ITEM NO. 1 2 3 5 6 8 9 10 11 DESCRIPTION Body Bonnet Plug & Stem Assembly Packing Follower Packing Guide Bushing Packing Spacer Cage Seat Ring (Metal or Soft Seat) ITEM NO. 12 13 14 15 16 17 19 20 23 DESCRIPTION ITEM NO. Bonnet Gasket 24 Gasket (Seat Ring) 25 Stud 26 Hex. Nut 39 Bonnet Stud 40 Stud Nut 41 Flange (Body 150# or 42 300#) 48 Split Ring 51 Seat Retainer (Soft Seat) 52 ITEMS NOT SHOWN 31 Cashco, Inc. P.O.