General Valve Twin Seal Iom
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ENGINEERED & PROCESS VALVES Installation, Operation and Maintenance Manual GENERAL VALVE® Twin Seal™ Double Block and Bleed Plug Valve GENERAL VALVE ® ENGINEERED & PROCESS VALVES Installation, Operation and Maintenance Manual 2 07/2011 / IOM-GEN-TWIN-03 ENGINEERED & PROCESS VALVES TABLE OF CONTENTS GENERAL VALVE ® TWIN SEAL ™ Installation. .................................................................................................... 4 Operation. ..................................................................................................... 5 Series 400, 800 & 900 Integral Bushing/Retained Ring Gland ............................................................ 6 Integral Bushing/Bolted Gland ........................................................................ 6 Bushings/One Gland ...................................................................................... 7 Bushings/Two Gland ...................................................................................... 7 Bearings/Duel Retention ................................................................................. 8 Bearings/Internally & Externally Retained ........................................................ 9 Bearings/Internal Retained with Two Glands................................................... 9 Series 8800...................................................................................................10 Operators Model 375H ..................................................................................................11 Model 500H & 625H......................................................................................12 Model 376G & 501G .....................................................................................14 Model 625G & 751G & 755G ........................................................................17 Model 1261G & 1261-7G ..............................................................................20 Model 1276G ................................................................................................23 Model 1500G ................................................................................................26 Bleeds The DTR System Explained .............................................................................29 Miscellaneous Operation & Maintenance ..............................................................................31 Parts ..............................................................................................................31 07/2011 / IOM-GEN-TWIN-03 3 Installation, Operation and Maintenance Manual ENGINEERED & PROCESS VALVES INSTALLATION Orientation Twin Seal valves may be installed in any position. Flow Direction The Twin Seal design is symmetrical. Flow shut-off is achieved equally on both sides of the plug independent of flow direction. Note: The use of a Differential Thermal Relief (DTR) as described on page 29 does result in a preferred flow direction. Flange Fasteners Certain Twin Seal flange holes are drilled and tapped, when there is no possibility of fitting a hexagonal nut behind the flange. The quantity and size of these tapped holes is shown in Table 2. Capscrews or stud bolts may be used in these holes. TABLE 2 Valve Size (inch) Clearance for Repair For easy repair, space should be allowed below the valve for removal of the lower plate and withdrawal of the seating slips. See Table 1 for dimensions. Sufficient clear space is required above the Twin Seal valve, to allow free movement of the position indicator flag and for removal of the operator mechanism. TABLE 1 Clearance required below standard ported valves for slip removal. Minimum Clearance Valve Size Inch ASME Class 150 ASME Class ASME Class ASME Class 300 600 900 6” 9” 9” 10” 8” 8” 13” 11” 12” 10” 10” 15” 13” 8” 10” 12” 17” 16” 10” 10” 14” 19” 15” 10” xxxx 16” 22” 19” 14” xxxx 18” 23” 13” xxxx xxxx 20” 26” 14” 14” xxxx 24” 28” 17” 12” xxxx 28” 30” 12” xxxx xxxx 30” 30” 28” xxxx xxxx 36” 30” xxxx xxxx xxxx Note: Allowing more than the specified minimum amount of clearance will make servicing easier. Installation, Operation and Maintenance Manual ASME Class 150 Number of Tapped Holes per Flange Thread UNC Length Required (inch) Cap Screws or Stud Bolts 6 150 4 3/4”-10 2 1/4 3 1/4 8 150 4 3/4”-10 2 1/4 3 1/4 8 300 4 7/8”-9 3 4 1/4 10 150 4 7/8”-9 2 1/4 3 1/4 10 300 4 1”-8 3 4 1/4 12 150 4 7/8”-9 2 1/4 3 1/2 12 300 4 1 1/8”-8 3 1/2 5 14 150 8 1”-8 2 1/2 4 14 600 4 1 3/8”-8 3 3/4 4 3/4 16 150 8 1”-8 2 1/2 3 3/4 18 150 8 1 1/8”-8 3 4 1/4 20 150 8 1 1/8”-8 3 4 1/2 24 150 8 1 1/4”-8 3 1/4 4 3/4 24 600 8 1 7/8”-8 5 1/4 6 3/4 28 150 6 1 1/4”-8 3 1/4 4 1/2 28 300 6 1 1/4”-8 3 1/4 4 1/2 30 150 6 1 1/4”-8 3 1/4 4 1/2 Gear Housing Orientation On gear-operated models the gear housing and associated hand wheel may be re-positioned as follows: A) Place valve in fully open position. B) Remove gear housing capscrews. C) Turn hand wheel to further open the valve which will turn the gear housing. Continue until hand wheel comes to the desired position and gear housing mounting holes are aligned. D) Replace gear housing mounting capscrews. NB: Short capscrew is inserted below the worm shaft. 4 07/2011 / IOM-GEN-TWIN-03 ENGINEERED & PROCESS VALVES Pressure Test Twin Seal valves can be hydrostatically pressure-tested after installation, to full API 6D limits per Table 3 below. Table 3 Valve figure No. ASME Class C411; C811; C911; 8811; C1611; C1500 C421; C821; C921; 8821; C1621; C1521 C441; C841; C941; C1641; C1541 C851; C1651; C1551 150 300 600 900 Comments Shell Test Pressure (Valve Open) (pisg) (kg/cm2) 500 35 1200 85 2250 158 3350 235 No leakage permitted Seat Test Pressure (Valve Closed) (psig) (kg/cm2) 300 21 800 56 1600 113 2400 168 Test upstream & downstream seats. No leakage permitted Supplimentary (API 598) Air Seat Test Pressure (Vavle Closed) (psig) (kg/cm2) 80 6 80 6 80 6 80 6 Test upstream & downstream seats. No leakage permitted OPERATION The Twin Seal valve is a non-lubricated, resilient seal, plugtype valve which has a mechanical means of freeing the plug before it is rotated from the closed to the open position. In opening the valve, the plug is raised, thus retracting the seating segments or slips through their tapered dovetail connections. Only after the slips are fully retracted perpendicularly from the body seat is the plug rotated to the open position. Since Twin Seal valves hold bubble-tight, for ease of opening in liquid service, it is important to prevent trapped body pressure from exceeding the working pressure of the valve. Therefore, a relief system is required to prevent pressure buildup in the body cavity. A B Conversely, in closing the valve, the plug and slips are rotated freely, with no seal-to-body contact until the slips are positioned over the ports. Then the plug is driven down between the slips and the tapered surfaces wedge out the slips for a positive upstream as well as downstream shut-off. For maximum upstream sealing, do not back off the hand wheel. Warning: Do not over torque by using cheater bars. The small Twin Seal valves are handwheel operated, and require up to 3 turns to open or close. Up to 2 3/4 turns expand or retract the slips, while 1/4 turn rotates the plug. Large valves operate in a similar manner, except that they have enclosed weather-proof worm gearing. C D At the top of the valve, a position indicator flag shows the exact plug position. It appears in line with the flow when the valve is open, and perpendicular to the flow when the valve is closed. 07/2011 / IOM-GEN-TWIN-03 5 Installation, Operation and Maintenance Manual ENGINEERED & PROCESS VALVES INTEGRAL BUSHING/RETAINING RING GLAND Typical Arrangement of: 2” C811 2” C821 3” CA811 3” CA821 The smallest of the Twin Seal valves do not require discrete bushings due to minimal hydro seating forces within the valve. Also note that due to the size of the operator, the gland is held in by a retaining ring backed up by the operator housing. INTEGRAL BUSHING/BOLTED GLAND Typical Arrangement of: 4” C811 The units do not require discrete bushings due to small hydro seating forces and by incorporating a slightly larger operator a bolt gland can be employed. Installation, Operation and Maintenance Manual 6 07/2011 / IOM-GEN-TWIN-03 ENGINEERED & PROCESS VALVES BUSHINGS/ONE GLAND Typical Arrangement of: 2” C841 6” C911 12” C811 2” C851 6” C921 12” C821 2” C861 6” C941 12” A1911 2” C911 8” C411 12” C921 2” C921 8” C421 14” C811 2” C941 8” C811 14” C821 3” C841 8” C821 14” C911 3” C911 8” C841 16” C411 4” C821 8” C911 16” C811 4” C841 8” C921 16” C821 4” C911 10” C411 16” C911/21 4” C921 10” C421 18” C411 4” C941 10” CA811 18” C811 6” C411 10” C821 20” C411 6” C421 10” C911 20” C421 6” C821 10” C921 20” CA811 6” C841 12” C411 24” C411 6” CA811 12” C421 24” C421 BUSHINGS/TWO GLAND Typical Arrangement of: 3” C851 3” C861 4” C851 6” C851 Higher pressure class valves employ the balanced plug design to minimize plug hydro forces which in turn requires two glands. 07/2011 / IOM-GEN-TWIN-03 7 Installation, Operation and Maintenance Manual ENGINEERED & PROCESS VALVES BEARINGS/DUAL RETENTION Typical Arrangement of: As valve size increases so does the plug load, therefore, these sizes require bearings. 12” C941 14” C841 16” C921 18” CA821 18” C911 20” CA821 20 CA841 20” C841 20” CA911 20” CA921 24” CA811 24” C811 24” C821 24” CA821 24” C911 28” C811 28” CC821 30” CC811 30” C821 BEARINGS/DUAL RETENTION Typical Arrangement of: 36” CA811 This valve requires bearings. The inner bearing retainer is slightly different than the one above. Installation, Operation and Maintenance Manual 8 07/2011 / IOM-GEN-TWIN-03 ENGINEERED & PROCESS VALVES BEARINGS/INTERNALLY & EXTERNALLY RETAINED Typical Arrangement of 10” CB841 10” C941 12” CB841 16” CA841 16” C941 20” CA921 24” C841 These valve sizes require bearings BEARINGS/INTERNALLY & RETAINED WITH TWO GLANDS Typical Arrangement of 8” C851 10” C851 High pressures require hydrostatically balanced plugs and two glands. 07/2011 / IOM-GEN-TWIN-03 9 Installation, Operation and Maintenance Manual ENGINEERED & PROCESS VALVES GENERAL VALVE® Twin Seal™ SERIES 8800 6 GLAND 77 LOCATING PIN 62B BACKUP RING 2 BONNET 62A O-RING 49 GASKET 62 O-RING 63 PACKING 4 PLUG 76 PIPE PLUG 72 CAP SCREW 5 SLIPS 76 PIPE PLUG 49 GASKET Typical Arrangement of: 1 BODY 62 O-RING 3 LOWER PLATE 2” 8851 2” 8861 3” 8851 6” 8821 8” 8811 8” 8821 10” 8811 10” 8821 12” 8811 12” 8821 62B BACKUP RING 62A O-RING 71 STUD 49 GASKET 62 O-RING 71 STUD 72 CAP SCREW 6 GLAND 62B O-RING 75A LIFTING LUG 63 PACKING 5 SLIPS 76 PIPE PLUG Typical Arrangement of: 4 PLUG 71 STUD 75 NUT 3 LOWER PLATE Installation, Operation and Maintenance Manual 14” 8811 16” 8811 18” 8811 20” 8811 24” 8811 NB: With the exception of 14”, 20” & 24” Models 8811G, remaining sizes all incorporate an internal coupling to connect valve with the operator. 1 BODY 76 PIPE PLUG 75 NUT 10 07/2011 / IOM-GEN-TWIN-03 ENGINEERED & PROCESS VALVES GENERAL VALVE® Twin Seal™ MODEL 375H Exploded View 19 Item No. 375 H Part No. Description Req’d 12 1 21-419 Operator Housing 1 14 8 2 22-417 Upper Stem 1 3 22-418 Lower Stem 1 4 27-418 Indicator Shaft 1 5 27-419 Indicator Flag 1 6 28-406 Handwheel 1 7 45-411 Key 1 8 46-425 Bushing 1 9 48-405 Roller 1 10 50-402 Grease Retainer 1 11 62-32 O-Ring 1 12 64-415 Protector 1 13 64-417 Insignia Plate 1 OPERATOR ASSEMBLY 14 65-402 Grease Seal 1 1. 2. 6 20 10 25 24 15 7 22 2 9 OPERATOR DISASSEMBLY 5 17 3 18 21 1 4 15 66-409 Ball Bearing 1 16 72-5 Capscrew 4 17 74-6 Screw 1 18 74-9 Set Screw 1 19 75-434 Nut 1 1. 2. 3. 4. 5. 6. 7. 8. 3. 16 23 13 11 20 76-411 Lube Fitting 1 21 77-407 Guide Pin 1 22 77-423 Drive Pin* 1 23 77-453 Roll Pin 1 24 78-413 Retaining Ring 1 25 78-414 Retaining Ring 1 4. 5. * not available separately. Cross Section 375 H is Used on Models: 5 8 5 17 12 4 19 7 25 6 2” C811 2” C821 3” CA811 3” CA821 6. 7. 10 24 15 8. 22 9 1 2 3 9. 11 18 21 10. 11. 16 07/2011 / IOM-GEN-TWIN-03 11 Unscrew (17) and remove indicator flag (5). Remove the stem protector (12). Remove the handwheel nut (19), handwheel (6), key (7) and grease retainer ring (10). Remove the retainer ring (25) and pull out the upper stem (2) with lower stem (3), bearing (15), roller (9) and indicator shaft subassembly (4) out through the top of the housing (1). Remove set screw (18) from bottom of lower stem and push indicator shaft subassembly (4) out through the bottom of the lower stem. Separate the stems and remove the retaining ring (24) and the bearing (15) from the upper stem. Remove grease seal (14) and bushing (8) (if required) from top of upper stem (2). Remove O-Ring (11) from inside housing. Install O-Ring (11) in housing (1). Place the bearing (15) on the top of the upper stem (2). Install retaining ring (24). Apply a liberal coating of grease to all surfaces of upper stem (2) and inside and outside of lower stem (3). Thread the upper stem and lower stem together such that the drive pin (22) in the upper stem comes against the shoulder at the TOP of the lower stem (3) and the detent recess in the upper stem is exactly in line with roller opening in the lower stem. NOTE: This operation may require several attempts as the threads are multiple start and do not always assemble correctly with the first try. Install the indicator shaft sub-assembly (4) up through both stems. Align the detent hole in the indicator disc with the threaded hole in the lower stem and fasten with set screw (18). Set screw must be below the outside surface of the lower stem. Place the roller (9) in the side opening of the lower stem. A liberal application of grease will hold the roller in position. Place the stem assembly into the housing taking care that roller is aligned with roller groove in housing. Push the entire assembly down until the bearing rests on the shoulder in the housing. Install the retaining ring (25) in the top of the housing (1). Install grease retainer (10) in handwheel (6) and place handwheel and key (7) on upper stem. Install bushing (8) and grease seal (14) in handwheel nut (19). Screw the nut on the upper stem and tighten down on handwheel securely. Install stem protector (12). Install indicator flag (5) and secure with screw(17). Installation, Operation and Maintenance Manual ENGINEERED & PROCESS VALVES GENERAL VALVE® Twin Seal™ MODEL 500H & 625H Exploded View Item No. 500 H Part No. 625 H Part No. Description 16 62-18 62-22 O-Ring 17 64-414 64-405 Plastic Plug 18 64-411 64-412 Protector 19 65-401 65-401 Grease Seal 20 66-402 66-403 Ball Bearing 21 72-4 72-4 Capscrew 22 72-5 72-6 Capscrew 23 72-6 72-11 Capscrew Handwheel 24 72-21 72-21 Capscrew 41-403 Guide Pin 25 74-1 74-3 Set Screw 41-404 41-404 Detent Pin 26 73-28 74-6 Screw 45-401 45-413 Key 27 75-427 75-429 Hex Nut 12 46-424 46-424 Bushing 28 76-411 76-411 Lube Fitting 13 47-401 47-401 Spring 29 77-402 77-403 Coupling Pin 14 48-401 48-403 Roller 30 78-403 78-404 Retaining Ring 15 62-17 62-17 O-Ring 31 93-413 93-413 Cover Item No. 500 H Part No. 625 H Part No. 1 21-411 21-407 Operator Housing 2 22-408 22-411 Upper Stem 3 41-405 41-406 Drive Pin* 4 22-409 22-413 Lower Stem 5 26-408 26-405 Housing Cap 6 27-406 27-406 Indicator Flag 7 27-404 27-438 Indicator Shaft 8 28-409 28-401 9 41-403 10 11 Description * not available separately. OPERATOR DISASSEMBLY 1. Unscrew (26) and remove indicator flag (6). 2. Remove the stem protector (18). 3. Remove bearing retainer nut (27). 4. Remove the handwheel (8) and key (11). 5. Unbolt and remove the housing cover (5). 6. Unbolt and remove the guide pin (9), with detent pin (10) and spring (13). 7. Pull the upper stem (2) with lower stem (4), roller (14), bearing (20) and indicator shaft (7) out through the top of the housing (1). If the bearing is snug in the housing, replace the handwheel and key. Turn the handwheel clockwise to raise the lower stem as far as possible. Insert a 3/8” diameter bar through the two holes in the bottom of the housing. Turn the handwheel clockwise and jack the bearing clear of the housing. 8. Remove the set screw (16) and push the indicator shaft subassembly (7) out through the bottom of the lower stem. 9. Remove the lower stem (4) from the upper stem (2). 10. Remove the retaining ring (30) and bearing (20) from the upper stem. 11. Remove the O-Ring (16) from the inside of the housing and grease seal (19) and bushing (12) (if required) from the top of the upper stem (2). Installation, Operation and Maintenance Manual 12 07/2011 / IOM-GEN-TWIN-03 ENGINEERED & PROCESS VALVES Cross Section 625 H is Used on Models: 500 H is Used on Models: 2” C851 2” C941 2” C841 2” C921 2” C861 4” C941 3” C841 3” C911 3” C851 6” C911 4” C811 4” C911 3” C861 6” C921 4” C821 4” C921 4” C841 6” CA811 4” C851 6” C821 8” C811 10” CA811 OPERATOR ASSEMBLY 1. Place the bearing (20) on upper stem (2). Install a retaining ring (30) to lock bearing in place. 2. Apply a liberal coat of grease to all surfaces of upper stem (2) below the bearing, and to all surfaces of the lower stem (4). Thread the upper stem (2) into the lower stem (4) such that the drive pin (3) in the upper stem comes against the shoulder at the TOP of the lower stem and the detent recess in upper stem is exactly in line with the roller opening in lower stem. NOTE: This operation may require several attempts as the threads are multiple start and do not always assemble correctly with the first try. 3. Install the indicator shaft assembly (7) up through both stems. Align the detent hole in the indicator disc with the threaded hole in the lower stem and fasten with set-screw (25). Set screw must be below the outside surface of the lower stem. 4. Install O-Ring (16) in housing (1). 5. Place roller (14) in opening of lower stem. A liberal application of grease will hold it in position. 6. Place the stem assembly into the housing - taking care that roller is aligned with roller groove in housing. Push entire assembly down until bearing rest on shoulder in housing. 7. Apply a smooth even coating of Form-a-Gasket® to surface of guide pin boss on housing (1). 8. Insert guide pin (14) with detent pin (10) and spring (13) to fully engage slot in lower stem and secure with capscrews (21). 9. Apply a smooth even coating of Form-a-Gasket® to top surface of housing (1). 10. Install O-Ring (15) in housing cover (5) and secure to housing (1) with capscrews (22). 11. Install the handwheel (8) and key (11). 12. Install the bearing retainer nut (27) and tighten securely. 13. Install grease seal (19) and bushing (12) in top of upper stem (2). 14. Install stem protector (18). 15. Install indicator flag (6) and secure with screw (26). 07/2011 / IOM-GEN-TWIN-03 13 Installation, Operation and Maintenance Manual ENGINEERED & PROCESS VALVES GENERAL VALVE® Twin Seal™ Model 376G & 510G Cross Section Exploded View 8 34 18 21 23 49-648-020 PLASTIC SHIM 6 11 11 29 9 7 12 17 24 20 2 9 26 25 4 19 27 16 13 5 14 21 3 32 10 34 24 8 21 25 31 2 1 27 23 15 26 29 4 18 11 12 3 16 5 28 7 19 Section A-A 17 20 23 21 13 24 25 31 1 14 6 27 32 UPPER 28 30 24-444 22 33 32 LOWER 10 35 30 15 (376 ONLY) Section B-B 501 G is Used on Models: 376 G is Used on Models: 2” C811 2” C821 3” CA811 3” CA821 Installation, Operation and Maintenance Manual 2” C841 2” C921 3” C841 3” C911 4” C811 4” C911 4” C821 4” C921 6” CA811 14 07/2011 / IOM-GEN-TWIN-03 ENGINEERED & PROCESS VALVES GENERAL VALVE® Twin Seal™ Model 376G & 510G OPERATOR DISASSEMBLY 1. Remove the indicator pin (34) and pull the indicator stem (8) up through the gear housing (2). 2. Remove the stop screw (35) and dowel pin (33). Drive out the upper coupling pin (32) and remove the coupling (10). 3. Remove the capscrew (29), washer (11), handwheel (9) and key (12). 4. Remove the four capscrews (27) and the gear housing cover (7). 5. Remove four capscrews (27) and lift off the gear housing (2). It may be necessary to turn the worm shaft counterclockwise to back the worm clear of the gear while lifting off the gear housing. The worm shaft (6) and the tapered bearing cup (24) and cone (25) on each end may now be removed from the gear housing (2). 6. The operator stem (3), upper stem (4), bearings (23), and roller (16) may now be lifted out of the operator housing. NOTE: The cam bushing (13) and stem bushing (14) are a press fit in the operator housing and should not be removed. Should the cam bushing require replacement, the operator housing must be returned. Item No. 376G Part No. 501G Part No. Description Req’d Item No. 376G Part No. 501G Part No Description Req’d 1 21-583 21-555 Operator Housing 1 18 62-83 62-70 O-Ring 1 2 21-584 21-554 Gear Housing 1 19 62-398 62-79 O-Ring 1 3 22-524 22-508 Operator Stem 1 20 62-91 62-91 O-Ring 1 4 23-560 23-525 Upper Stem 1 21 62-371 62-339 O-Ring 2 5 77-465 77-464 Pin* 1 22 - 64-424 Caplug 6 24-451 24-445 Worm Shaft 1 23 66-483 66-476 Ball bearing 2 7 26-632 26-580 Gear Housing Cover 1 24 66-481 66-477 Cup Bearing 2 8 27-545 27-504 Stem Indicator 1 25 66-482 66-478 Cone Bearing 2 9 28-441 28-442 Handwheel 1 26 69-414 69-414 Spinner Handle 1 10 32-476 32-469 Coupling 1 27 72-5 72-5 Capscrew 8 11 44-465 44-453 Handwheel Washer 1 28 72-16 72-10 Capscrew 4 12 45-431 45-431 Key 1 29 72-21 72-26 Capscrew 1 13 46-557 46-501 Cam Bushing 1 30 76-891 76-594 Plug 1 14 46-558 46-502 Stem Bushing 1 31 76-612 76-612 Lube Fitting 1 15 46-559 - Pilot Bushing 1 32 77-422 77-417 Coupling Pin 2 16 48-405 48-401 Roller 1 33 77-480 77-418 Dowel Pin 1 17 62-71 62-34 O-Ring 1 34 77-451 77-440 Indicator Pin 1 35 98-790 98-663 Stop Screw 1 * not available separately. 07/2011 / IOM-GEN-TWIN-03 15 Installation, Operation and Maintenance Manual ENGINEERED & PROCESS VALVES OPERATOR ASSEMBLY 1. Install O-Ring (21) in the stem bushing (14) in the operator housing (1). Place bearing (23) in the top of the operator housing (1). 2. Apply a liberal coating of grease to all surfaces of the operator stem (3) and the upper stem (4). Thread the operator stem into the upper stem such that the dowel pin (5) comes against the shoulder at the BOTTOM of the upper stem and the detent recess in the operator stem is exactly in line with the roller opening at the bottom of the upper stem. This operation may require several attempts as the threads are multiple start and do not always assemble correctly with the first try. 3. Place the roller (16) in the opening of the upper stem (4) and the detent recess of the operator stem (3). An application of grease will hold it in position. 4. Position the operator housing such that when viewed from above, the raised portion of the cam is in the lower left quadrant of the housing bore (see cross-section illustration). With the roller on the left side, place the upper stem, operator stem and roller (which have been assembled together–see steps 2 & 3) into the operator housing (1), down through the stem bushing (14) and cam roller bushing (13) until the shoulder of the upper stem (4) is against the bearing (23). 5. Install bearing (23) in the gear housing (2). Install the O-Ring (21) in the top of the gear housing (2). 6. Install the tapered roller bearing cup (24) in the recess of the gear housing with the large diameter of the taper facing out. 7. Install tapered roller bearing cup (24) and cone (25) on the handwheel end of the worm shaft (6). Place bearing cone (25) on the opposite end of the worm shaft with the large diameter of the taper against the shaft shoulder. Apply a liberal amount of grease to all parts. 8. Install the worm shaft in the gear housing. Make certain that the rear bearing cone has properly entered the rear bearing cup. 9. Install O-Rings (17) and (20) in the gear housing cover (7) and assemble to the gear housing (2) with four of the capscrews (27). Run the screws in just enough to keep parts in place but do not tighten at this time. 10. Install O-Ring (19) in the top of the operator housing. Place the gear housing on the operator housing with the worm gear on the left side as viewed from the top (same side as the roller) and fasten with four of the capscrews (27). NOTE: Worm shaft must be moved out slightly to allow parts to assemble. Tighten capscrews (27) in gear housing cover (7). 11. Assemble handwheel (9), key (12), washer (11) and capscrew (29) on the worm shaft. 12. Place a drift punch through the hole in the top of the operator stem to prevent it from turning. With the punch at 90° to the worm shaft, turn the handwheel clockwise and run the upper stem down as far as it will go. Place the coupling (10) on the bottom of the operator stem with the horizontal portion of the L-shaped groove at the bottom. Turn the coupling until the coupling pin hole in the operator stem is aligned with the top hole in the coupling, and the vertical groove without the ramp is aligned with the stop screw boss in the housing. Drive the coupling (32) into the hole in the top of the coupling and the bottom hole of the operator stem. Install the stop screw (35) and the dowel pin (33). NOTE: The coupling (10) has an L-shaped groove on both sides. The vertical portion of one of the grooves has a ramp at the top. The coupling must be installed such that the side without the ramp is adjacent to, and engages the stop screw. (The ramp is used to actuate the automatic body bleed valve when installed). 13. Install O-Ring (21) in the top of the gear housing and O-Ring (18) in the top of the lower stem (3). Place the indicator stem (8) on the top of the operator stem and down through the gear housing. Install the indicator pin (34). Installation, Operation and Maintenance Manual 16 07/2011 / IOM-GEN-TWIN-03 ENGINEERED & PROCESS VALVES GENERAL VALVE® Twin Seal™ Model 625G, 751G & 755G Cross Section Exploded View 34 17 26 28 18 7 32 8 41 13 32 17 21 34 26, 28 7 8 21 18 29 11 39 24 36 11 39 24 16 9 13 25 36 9 10 27 27 43 6 25 16 10 29 6 19 2 35 1 4 33 5 20 2 10 19 31 14 3 12 22 38 15, 42 23 40, 30 43 4 5 20 625G is Used on Models: 2” C941 6” C841 8” C911 2” C861 2” 8851 8” C821 10” C911 3” C851 2” 8861 10” C821 12” 8811 3” 8851 4” C941 12” C811 14” 8811 3” C861 6” C911 4” C841 6” C921 6” C821 6” 8821 8” C811 8” 8811 10” CA811 10” 8811 12 38 751G is Used on Models: 2” C851 3 14 44 37 31 35 1 14” C811 23 15/42 30/40 22 755G is Used on Models: 6” C851 8” C941 8” CA841 07/2011 / IOM-GEN-TWIN-03 17 Installation, Operation and Maintenance Manual ENGINEERED & PROCESS VALVES GENERAL VALVE® Twin Seal™ Model 625G, 751G, & 755G OPERATOR DISASSEMBLY 1. 2. 3. 4. 5. 6. 7. 8. Unscrew (39) and remove indicator flag (11). Remove stem protector (24). Unbolt and remove gear housing cover (9). Remove bearing retainer nut (16). Remove bearing carrier (10) and upper bearing (27). Remove upper retaining ring (43). Remove capscrew (34), washer (17), handwheel (13) and key (18). Unbolt and remove bearing cap (8). CAUTION: DO NOT DAMAGE PLASTIC SHIMS. 9. 10. 11. 12. 13. 14. 15. 16. Screw out the worm shaft (7). Front bearing cone (26) and cup (28) and rear bearing cone (26) will come out with the worm shaft. Rear bearing cup (28) can then be removed from gear housing (2). Remove the worm gear (6) and key (19). Unbolt and remove the gear housing (2). Unbolt and remove the guide pin (14). Pull the upper stem (4) with lower stem (3), roller (20), lower bearing (27) and indicator shaft (12) out through the top of the housing (1). If the bearing is snug in the housing, install the worm gear with its key on the upper stem upside down (hub up). Turn the gear counter clockwise to raise the lower stem as far as possible. Insert a 1/2” diameter bar through the two holes in the bottom of the housing. Using a pipe wrench on the gear hub, turn clockwise and jack the bearing clear of the housing. Remove the set screw (38) and push the indicator shaft sub-assembly (12) out through the bottom of the lower stem. Remove the lower stem (3) from the upper stem (4). Remove the retaining ring (43) and lower bearing (27) from the upper stem. Item No. 625G Part No. 751G Part No. 755G Part No. Description Item No. 625G Part No. 751G Part No. 755G Part No Description 1 21-422 21-623 21-623 Operator Housing 24 64-411 64-411 64-411 Protector 2 21-408 21-405 21-443 Gear Housing 25 65-401 65-401 65-401 Grease Seal 3 22-440 22-555 22-555 Lower Stem 26 65-401 65-401 65-401 Bearing Cone 4 22-439 22-554 22-554 Upper Stem 27 66-412 66-410 66-410 Bearing Ball 5 41-406 41-401 41-401 Drive Pin* 28 66-458 66-458 66-458 Bearing Cup 6 23-402 23-403 23-406 Worm Gear 29 69-414 69-414 69-414 Spinner Handle 7 24-404 24-404 24-403 Worm Shaft 30 72-11 - - Stud 72-4 72-4 72-4 Capscrew 8 26-401 26-401 26-401 Bearing Cap 31 9 26-413 26-403 26-403 Gear Housing Cover 32 72-5 72-5 72-5 Capscrew 10 26-412 26-411 26-423 Bearing Carrier 33 72-10 72-6 - Capscrew 11 27-406 27-406 27-406 Indicator Flag 34 72-8 72-8 72-8 Capscrew 12 27-429 27-435 27-435 Indicator Shaft 35 72-9 72-9 72-9 Capscrew 72-14 72-14 72-26 Capscrew 13 28-404 28-402 28-402 Handwheel 36 14 41-407 41-498 41-498 Guide Pin 37 72-21 72-21 72-21 Capscrew 15 77-403 41-410 41-410 Coupling Pin 38 74-3 74-4 73-28 Set Screw 16 75-462 42-401 42-401 Hex Nut 39 74-6 74-6 74-6 Screw 17 44-401 44-401 44-401 Washer 40 - 73-130 73-130 Hex Nut 18 45-402 45-402 45-402 Woodruff Key 41 76-612 76-612 76-612 Lube Fitting - 78-406 78-406 Retaining Ring 19 45-403 45-406 45-406 Straight Key 42 20 48-403 48-413 48-413 Roller 43 78-404 78-408 78-408 Retaining Ring 21 62-13 62-13 62-13 O-Ring 44 93-413 93-413 93-413 Cover 22 62-22 62-209 62-209 O-Ring 23 64-405 64-402 64-402 Plastic Plug Installation, Operation and Maintenance Manual 18 07/2011 / IOM-GEN-TWIN-03 ENGINEERED & PROCESS VALVES OPERATOR ASSEMBLY 1. Place one of the two bearings (27) on upper stem (4). NOTE: This bearing is assembled such that the wide surface of the inner race seats on the upper stem shoulder. Install a retaining ring (43) to lock the bearing in place. NOTE: The retaining ring comes against narrow surface of inner race. 2. Apply liberal coat of grease to all surfaces of the upper stem below the bearing. Thread the upper stem (4) into the lower stem (3) such that stop pin (5) in the upper stem comes against the shoulder at the TOP of the lower stem and the detent recess in upper stem is exactly in line with the roller opening in lower stem. This operation may require several attempts as the threads are multiple start and do not always assemble correctly with the first try. 3. Install the indicator shaft assembly (12) up through both stems. Align the detent hole in the indicator disc with the threaded hole in the lower stem and fasten with set screw (38). Set screw must be below the outside surface of the lower stem. 4. Install O-Ring (22) in housing (1). 5. Place roller (20) in opening of lower stem. A liberal application of grease will hold it in position. 6. Place the stem assembly into the housing–taking care that roller is aligned with roller groove in housing. Push entire assembly down until bearing rests on shoulder in housing. 7. Apply a smooth even coating of Form-a-Gasket® to surface of guide pin boss on housing (1). 8. Insert guide pin (14) to full engage slot in lower stem and secure with capscrews (31). 9. Place gear key (19) 10. Install tapered roller bearing cup (28) in rear bearing recess of gear housing (2) with large diameter of taper facing out. 11. Install tapered roller bearing cup (28) and cone (26) on handwheel end of worm shaft (7). Place bearing cone (26) on opposite end with large diameter of taper against shaft shoulder. 12. Install worm shaft in gear housing. Make certain that rear bearing cone has properly entered rear bearing cup (28). 13. Install O-Ring (21) in bearing cap (8). 14. Apply a smooth even coating of Form-a-Gasket® to bearing cover boss on gear housing. Fasten bearing cap (8) in place with capscrews (32). Be sure to install the plastic shims between gear housing and bearing cap. 15. Install worm gear (6) in gear housing with hub down (toward smaller opening). 16. Apply Form-a-Gasket® to top flange of operator housing (1). Place gear housing (2) with assembled parts on top of operator housing guiding worm gear keyway over key (19) in upper stem (3). 17. Install retaining ring (43) to secure worm gear (6). 18. Fasten gear housing (2) to operator housing (1) with capscrews (35). CAUTION: NOTE THAT THE SHORT CAP SCREW (33) IS INSTALLED DIRECTLY UNDER THE CENTER OF THE WORM SHAFT (7). 19. Fill gear housing (2) with grease up to top of worm gear. 20. Install bearing (27) in bearing carrier (10). NOTE: The widest surface of the outer race goes against the shoulder in the bearing carrier. 21. Apply a smooth even coating of Form-a-Gasket® over top surface of gear housing (2). 22. Place bearing carrier (10) on top of gear housing (2). Install two capscrews (36) 180° apart to temporarily align the bearing carrier. They need only be partially screwed in. 23. Install lock nut (16) on upper stem and tighten snug with a wrench. Remove the two capscrews (36). 24. Install the grease seal (25) in the gear housing cover (9). Slide the cover over the indicator shaft (12) and secure to top of gear housing (2) with capscrews(36). 25. Install stem protector (24). 26. Install indicator (11) and secure with socket head capscrew (39). 07/2011 / IOM-GEN-TWIN-03 19 Installation, Operation and Maintenance Manual ENGINEERED & PROCESS VALVES GENERAL VALVE® Twin Seal™ Model 1261G 1261-7G Exploded View Cross Section 29 34 16 30 8 34 16 17 6 30 8 28 17 29 6 11 20 28 27 11 39 28 27 28 27 37 9 22 2 33 7 24 28 27 15 25 37 8 22 10 24 33 7 15 25 5 2 18 11 5 39 2 39 40 26 26 35 31 19 36 42 38 40 26 3 1 12 3 19 32 13 4 21 41 14 12” C821 8” C921 14” C821 10” CA921 16” C811 12” CA911 16” 8811 14” C911 18” C811 16” C911 4 38 13 32 23 41 14 35 10 42 36 23 1261G is Used on Models: 18 12 43 NOT SHOWN 1 31 41 23 21 1261-7G is Used on Models: 18” 8811 8” C851 12” CA921 10” CB841 18” C911 12” CB8411 20” CA911 16” CA821 20” CA811 18” CA821 20” 8811 24” CA811 24” 8811 Installation, Operation and Maintenance Manual 20 07/2011 / IOM-GEN-TWIN-03 ENGINEERED & PROCESS VALVES GENERAL VALVE® Twin Seal™ Model 1261G & 1261-7G OPERATOR DISASSEMBLY 1. Unscrew (37) and remove indicator flag (9). 10. Unbolt and remove the gear housing (2). 2. Remove indicator shaft protector (22). 11. Remove the retaining ring (40). 3. Unbolt and remove gear housing cover (7). 12. Unbolt and remove the guide pin (13). 4. Remove upper stem nut (15). 13. 5. Remove upper bearing (25). 6. Remove capscrew (34), handwheel washer (16), hand wheel (11) and woodruff key (17). 7. Unbolt and remove bearing cap (8). CAUTION: DO NOT DAMAGE PLASTIC SHIMS. Pull the upper stem (3) with the lower stem (4), roller (19), two bearings (26) and indicator shaft (10) out through the top of the housing (1). If the bearings are snug in the housing, install the worm gear (5) with its key (18) on the upper stem upside down (hub up). Turn the gear counter-clockwise to raise the lower stem as far as possible. Insert a 1 1/2” diameter bar through the two holes in the bottom of the housing. Using a pipe wrench on the gear hub, turn clockwise and jack the bearing clear of the housing. 8. Screw out worm shaft (6). Front bearing cone (27) and cup (28) and rear bearing cone (27) will come out with the worm shaft. Rear bearing cup (28) can then be removed from gear housing. 14. Remove the socket head capscrew (38) and push the indicator shaft subassembly (10) out through the bottom on the lower stem (4). 9. Remove the worm gear (5) and key (18). 15. Remove the lower stem (4) from the upper stem (3). 16. Remove the bearings (26) from the upper stem (3). Item No. 1261G Part No. 1261-7G Part No. Description Req’d Item No. 1261G Part No. 1261-7G Part No. Description Req’d 1 21-621 21-621 Operator Housing 1 24 65-401 65-401 Grease Seal 1 2 21-518 21-518 Gear Housing 1 25 66-404 66-404 Ball Bearing 2 3 22-552 22-552 Upper Stem 1 26 66-411 66-411 Ball Bearing 2 4 22-553 22-553 Lower Stem 1 27 66-465 66-465 Bearing Cone 2 5 23-472 23-472 Worm Gear 1 28 66-466 66-466 Bearing Cup 1 6 24-428 24-428 Worm Shaft 1 29 69-414 69-414 Spinner Handle 4 7 26-513 26-513 Gear Housing Cover 1 30 72-2 72-2 Capscrew 1 8 26-514 26-514 Bearing Cap 1 31 72-3 72-3 Capscrew 2 9 27-406 27-406 Indicator Flag 1 32 72-4 72-4 Capscrew 8 10 27-488 27-488 Indicator Shaft 1 33 72-7 72-7 Capscrew 1 11 28-402 28-402 Handwheel 1 34 72-8 72-8 Capscrew 7 12 41-402 41-402 Drive Pin* 1 35 72-13 72-13 Capscrew 2 13 41-496 41-496 Guide Pin 1 36 72-21 72-21 Capscrew 1 14 41-411 41-411 Coupling Pin 1 37 73-28 74-6 Screw 1 15 42-403 42-403 Nut 1 38 73-28 74-12 Set Screw 2 16 44-401 44-401 Handwheel Washer 1 39 76-412 76-412 Lube Fitting 1 17 45-402 45-402 Woodruff Key 1 40 78-405 78-405 Retaining Ring 2 18 45-404 45-404 Key 1 41 78-407 78-407 Retaining Ring 1 19 48-412 48-412 Roller 1 42 93-413 93-413 Cover 1 20 62-13 62-13 O-Ring 1 43 - 26-712 Adapter 1 21 62-208 62-208 O-Ring 1 22 64-411 64-411 Protector 1 23 64-416 64-416 Plastic Plug 2 07/2011 / IOM-GEN-TWIN-03 21 Installation, Operation and Maintenance Manual ENGINEERED & PROCESS VALVES GENERAL VALVE® Twin Seal™ Model 1261G & 1261-7G OPERATOR ASSEMBLY 1. Install the two bearings (26) at top of upper stem (3). NOTE: These are radial thrust bearings and must be installed such that the widest surfaces of the inner raceways are back to back. NOTE: INCORRECT INSTALLATION WILL RESULT IN SERIOUS DAMAGE. 2. Install the bearing retaining ring (40). 3. Apply a liberal coating of grease to all surfaces of the upper stem (3). 4. Thread the upper stem (3) into the lower stem (4) such that the drive pin in the upper stem comes against the shoulder at the TOP of the lower stem and the detent recess in the upper stem is exactly in line with the roller opening in the lower stem. This operation may require several attempts as the threads are multiple start. 5. Install the indicator shaft sub-assembly (10) up through both stems. 6. Install O-Ring (21) in housing (1). 7. Place the roller (48) in the side opening of the lower stem (4). 8. Place the stem assembly into the housing (1) taking care that the roller (48) is aligned with the roller groove in the housing. Push the assembly down until the lower bearing (26) rests on the shoulder in the housing. 9. Apply a smooth even coating of Form-a-Gasket® to the surface of the guide pin boss on the housing (1). 10. Insert the guide pin (13) to full engage the slot in the lower stem (4) and fasten with capscrews (32). 11. Place gear key (18) in keyway of upper stem (3). 12. Install tapered roller bearing cup (28) in rear bearing recess of gear housing (2) with large diameter of taper facing out. 13. Install tapered roller bearing cup (28) and cone (27) on handwheel end of worm shaft (6). 14. Install worm shaft (6) in gear housing (2). Make certain that rear bearing cone (27) has properly entered the rear bearing cup (28). 15. Install O-Ring (20) in bearing cap (8). 16. Apply a smooth coating of Form-a-Gasket® to bearing cap boss on gear housing (2). Fasten bearing cap in place with cap screws (30). Be sure to install the plastic shims between the gear housing and the bearing cap. 17. Install worm gear (6) in gear housing (2) hub down (toward smallest opening). 18. Place the gear housing (2) with assembled parts on top of the operator housing guiding the worm gear keyway over key (18) in upper stem (3). 19. Install the ball bearing (25) on the upper stem (3) and secure with nut (15). 20. Apply a smooth coating of Form-a-Gasket® to top of operator housing. 21. Fasten the gear housing (2) to the operator housing with capscrews (35 and 3). CAUTION: NOTE THAT THE SHORT CAPSCREW (72B) IS INSTALLED DIRECTLY UNDER THE CENTER OF THE WORM. 22. Fill the gear housing (2) with grease up to the top of the worm gear (5). 23. Apply a smooth coating of Form-a-Gasket® to top surface of gear housing (2). 24. Install grease seal (24) in gear housing cover (7). Slide cover over indicator shaft (10) and ball bearing (25) and secure to top of operator housing with capscrews (33). 25. Install the indicator shaft protector (22). 26. Install the indicator flag (9) and secure with screw (37). 27. Install handwheel (11) with woodruff key (17), washer (16) and capscrew (34). Installation, Operation and Maintenance Manual 22 07/2011 / IOM-GEN-TWIN-03 ENGINEERED & PROCESS VALVES GENERAL VALVE® Twin Seal™ Model 1276G Exploded View Cross Section 31 34 18 19 11 24 35 26 36 41 10 22 9 39 8 17 41 27 6 9 3 9 7 29 30 49-649-20 SHIM (NOT SHOWN) 36 7 29 30 19 28 29 30 13 31 39 12 41 20 26 17 5 18 34 8 14 22 10 11 24 5 13 21 35 27 4 6 2 28 3 38 21 4 2 1 43 45 38 33 25 15 45 42 37 1 36 20 23 36 23 40 32 43 40 32 33 16 16 12 44 15 44 42 25 37 1276G is Used on Models: 10” C851 16” C921 16” CA841 20” CB921 20” CA821 24” CA821 30” CC811 07/2011 / IOM-GEN-TWIN-03 23 Installation, Operation and Maintenance Manual ENGINEERED & PROCESS VALVES GENERAL VALVE® Twin Seal™ Model 1276G OPERATOR DISASSEMBLY Item No. 1276G Part No. Description 12 27-541 Indicator Shaft Req’d 1. Turn handwheel counter clockwise to full open position. 2. Remove set screw (39) and indicator flag (11). 13 28-432 Handwheel 3. Remove the stem protector (24). 14 41-473 Drive Pin* 4. Unbolt and remove the gear housing cover (8). 15 41-476 Coupling Pin 16 41-480 Guide Pin 17 42-403 Nut 1 Remove capscrew (34), washer (18), handwheel (13) and key (19). 18 44-401 Washer 1 19 45-402 Key 1 Unbolt and remove the bearing caps (9) and (10). 20 45-428 Key 1 21 48-409 Roller 1 22 62-20 O-Ring 1 5. 6. 7. Remove the bearing retainer nut (17) and ball bearing (27). CAUTION: DO NOT DAMAGE THE PLASTIC SHIMS UNDER FRONT BEARING CAP (10). 8. Remove worm shaft (7) and taper bearings consisting of cone (29) and cup (30). 23 62-215 O-Ring 1 24 64-412 Protector 1 9. Remove worm gear (6) and key (20). 25 64-416 Plastic Plug 4 10. Unbolt and remove the gear housing (3). 26 65-401 Grease Seal 1 27 66-404 Ball Bearing 1 28 66-452 Ball Bearing 2 29 66-454 Bearing Cone 2 30 66-463 Bearing Cup 2 31 69-414 Spinner Handle 1 32 71-47 Stud 12 33 72-5 Capscrew 2 34 72-8 Capscrew 1 35 72-26 Capscrew 8 36 72-64 Capscrew 12 11. Unbolt and remove the guide pin (16). 12. Pull the upper stem (5) and lower stem (4) with bearings (28) and roller (21) out through the top of the upper housing (2). If bearings are snug in the upper housing, remove the upper and lower stems with the roller through the bottom of the lower housing (1). Unbolt the upper and lower housing and remove the bearings with a suitable puller. 13. Separate the upper and lower stems and remove indicator shaft assembly (12). 37 73-111 Capscrew 6 Item No. 1276G Part No. Description Req’d 38 73-131 Capscrew 12 1 21-594 Lower Housing 1 39 74-6 Screw 1 2 21-595 Upper Housing 1 40 75-406 Nut 24 41 76-412 Lube Fitting 2 42 76-536 Pipe Plug 1 43 77-454 Dowel Pin 1 44 77-481 Rollpin 1 45 78-407 Retaining Ring 2 3 21-505 Gear Housing 1 4 22-533 Lower Stem 1 5 22-534 Upper Stem 1 6 23-461 Worm Gear 1 7 24-425 Worm Shaft 1 8 26-487 Gear Housing Cover 1 9 26-488 Bearing Cap 1 10 26-489 Bearing Cap 1 11 27-406 Indicator Flag 1 Installation, Operation and Maintenance Manual *not available separately 24 07/2011 / IOM-GEN-TWIN-03 ENGINEERED & PROCESS VALVES GENERAL VALVE® Twin Seal™ Model 1276G OPERATOR ASSEMBLY 1. Install the two bearings (28) at the top end of the upper stem (5). NOTE: These are radial thrust bearings and must be installed such that the widest surfaces of the inner race ways are back to back. INCORRECT INSTALLATION WILL RESULT IN SERIOUS DAMAGE. 2. Apply a smooth even coating of Permatex Number 3D to the bottom flange of the upper housing (2) and fasten to the lower housing (1) with studs (32) and nuts (40). The dowel pin (43) is a press fit in the lower housing and a slip fit in the upper housing. Its function is to properly align the roller grooves. 3. Apply a liberal coating of grease to all surfaces of upper stem (5) and lower stem (4). 4. Thread the two stems together such that the drive pin (14) in the upper stem comes against the shoulder at the top of the lower stem and the detent recess in the upper stem is exactly in line with the roller opening in the lower stem. This operation may require several attempts as the threads are multiple start and do not always assemble correctly with the first try. 5. Install the indicator shaft sub-assembly up through both stems and secure with the roll pin (44) in the bottom of the lower stem. 6. Install O-Ring (23) in the lower housing (1). 7. Place the roller (21) in the side opening of the lower stem (4). A liberal application of grease will hold it in place. 8. Place the stems with bearings and roller assembled down through the top of the upper housing until the lower of the two bearings (28) rests on the shoulder in the upper housing. 9. Apply a smooth even coating of Form-a-Gasket® to the surface of the guide pin boss on the lower housing (1). 10. Insert the guide pin (16) to fully engage the slot in the lower stem and fasten with cap screws (33). 11. Place the gear key (20) in the keyway of the upper stem (5). 12. Place the tapered roller bearing cones (29) on each end of the worm shaft (7) with the large diameter of the cone taper against each shaft shoulder. 13. Assemble the cups (30) on the cones (29). 14. Apply a smooth even coating of Form-a-Gasket® to the surfaces of the bearing retainer bosses on the gear housing (3). 15. Fasten the blind bearing cap (9) in place with capscrews (36). 16. Install the worm shaft (7) in the gear housing. 17. Install the O-Ring (22) in the bearing cap (10) and fasten in place with capscrews (36). Be sure to re-install the plastic shims between the gear housing and the bearing cap. 18. Install worm gear (6) in gear housing with hub down. (Toward smallest opening). 19. Apply a smooth coating of Form-a-Gasket® to top flange of upper housing. 20. Place the gear housing with assembled parts on top of the upper housing guiding the worm gear keyway over the key (20) in the upper stem, and fasten to the upper housing with capscrews (38). 21. Install ball bearing (27) over upper stem and secure with nut (17). 22. Fill the gear housing with grease up to the top of the worm gear. 23. Apply a smooth even coating of Form-a-Gasket® around top surface of gear housing. 24. Install the grease seal (26) in the gear housing cover (8). Slide the cover over the indicator shaft (12) and the ball bearing (27) and secure to the top of the operator housing with capscrews (35). 25. Install the stem protector (24) and secure the indicator flag (11) in place with set screw (39). 26. Install the handwheel (13) with key (19), washer (18), capscrew (34) and spinner handle (31). 07/2011 / IOM-GEN-TWIN-03 25 Installation, Operation and Maintenance Manual ENGINEERED & PROCESS VALVES GENERAL VALVE® Twin Seal™ Model 1500G Cross Section Exploded View 34 18 19 31 39 11 24 35 26 8 10 22 17 27 30 29 6 9 41 36 7 3 9 36 7 29 30 19 28 29 30 41 31 11, 39 41 20 24 26 8 14 22 10 18 34 35 13 5 21 39, 40 4 6 36 27 38 2 28 19 2 5 21 42 **SHIELDS (NOT SHOWN) 25-93-424 25-93-492 1 32, 40 1500F is Used on Models: 16, 33 20” C841 4 44 30” CC821 23 12 36” CA811 16” C941 43 15, 45 46 37 *Handwheel not shown Installation, Operation and Maintenance Manual 26 07/2011 / IOM-GEN-TWIN-03 ENGINEERED & PROCESS VALVES GENERAL VALVE® Twin Seal™ Model 1500G OPERATOR DISASSEMBLY 1. 2. 3. 4. 5. 6. 7. Turn worm shaft counter-clockwise to full open position. Remove set screw (39) and indicator flag (11) Remove the stem protector (24). Unbolt and remove the gear housing cover (8). Remove the set screw (39), and upper stem nut (17). Remove the ball bearing (27). Unbolt and remove bearing cap (10). CAUTION: DO NOT DAMAGE THE PLASTIC SHIMS UNDER MOTOR ADAPTER. 8. 9. 10. 11. 12. 13. Remove the worm shaft (7) and taper bearings consisting of cones (29) and cups (30). Remove worm gear (6) and key (20). Unbolt and remove the gear housing (3). Unbolt and remove the guide pin (16). Pull the upper stem (5) and lower stem (4) with bearings (28), bearing retainer and roller (21) out through the top of the upper housing (2). If bearings are snug in the upper housing, remove the upper and lower stems with the roller through the bottom of the lower housing. Unbolt the upper and lower housings and remove the bearings with a suitable puller. Separate the upper and lower stems and remove the nut (43) and indicator shaft (12). Item No. 1500G Part No. Description Req’d Item No. 1500G Part No. Description Req’d 1 21-572 Lower Housing 1 27 66-424 Ball Bearing 1 2 21-571 Upper Housing 1 28 66-425 Ball Bearing 1 3 21-573 Gear Housing 1 29 66-454 Bearing Cone 2 4 22-510 Lower Stem 1 30 66-463 Bearing Cup 2 5 22-509 Upper Stem 1 31 69-414 Spinner Handle 1 6 23-411 Worm Gear 1 32 71-109 Stud 12 7 24-425 Worm Shaft 1 33 72-5 Capscrew 2 8 26-515 Gear Housing Cover 1 34 72-8 Capscrew 1 9 26-488 Bearing Cap 1 35 72-26 Capscrew 8 10 26-489 Bearing Cap 1 36 72-64 Capscrew 12 11 27-406 Indicator Flag 1 37 73-87 Capscrew 12 12 27-450 Indicator Shaft 1 38 73-124 Capscrew 12 13 28-432 Handwheel 1 39 74-6 Screw 1 14 41-474 Drive Pin* 1 40 75-408 Nut 24 15 32-410 Coupling Pin 1 41 76-412 Lube Fitting 2 16 41-474 Guide Pin 1 42 76-470 Pipe Plug 1 17 75-441 Nut 1 43 75-441 Nut 1 18 44-401 Washer 1 44 72-21 Capscrew 30 19 45-402 Key 1 45 75-442 Coupling Pin Nut 2 20 45-414 Key 1 46 32-452 Spacer 1 21 48-408 Roller 1 22 62-20 O-Ring 1 23 62-89 O-Ring 1 24 64-412 Protector 1 25 - Oper. Shield 2 26 65-401 Grease Seal 1 07/2011 / IOM-GEN-TWIN-03 *not available separately 27 Installation, Operation and Maintenance Manual ENGINEERED & PROCESS VALVES GENERAL VALVE® Twin Seal™ Model 1500G OPERATOR ASSEMBLY 1. Install the two bearings (28) and bearing retainer at the top end of the upper stem (5). NOTE: These are radial thrust bearings and must be installed such that the widest surfaces of the inner raceways are back to back. INCORRECT INSTALLATION WILL RESULT IN SERIOUS DAMAGE. 2. Apply a smooth even coating of Form-a-Gasket® to the bottom flange of the upper housing (2) and fasten to the lower housing (1) with studs (32) and nuts (40). 3. Apply a liberal coating of grease to all surfaces of the upper stem (5) and lower stem (4). 4. Thread the two stems together such that the drive pin in the upper stem comes against the shoulder at the top of the lower stem and the detent recess in the upper stem is exactly in line with the roller opening in the lower stem. This operation may require several attempts as the threads are multiple start and do not always assemble correctly with the first try. 5. Install the indicator shaft (12) up through both stems and secure with nut (43) in the bottom of the lower stem. 6. Install O-Ring (23) in the lower housing. 7. Place the roller (21) in the side opening of the lower stem (4). A liberal application of grease will hold it in place. 8. Place the stems with bearings (28), bearing retainer and roller (21) assembled down through the top of the upper housing until the lower of the two bearings rests on the shoulder in the upper housing. 9. Apply a smooth even coating of Form-a-Gasket® to the surface of the guide pin boss on the lower housing. 10. Insert the guide pin (16) to fully engage the slot in the lower stem and fasten with cap screws (33). 11. Place the gear key (20) in the keyway of the upper stem. 12. Place the tapered roller bearing cones (29) on each end of the worm shaft (7) with the large diameter of the cone taper against each shaft shoulder. 13. Assemble the cups (30) on the cones. 14. Install the worm shaft in the gear housing. 15. Apply a smooth even coating of Form-a-Gasket® to motor adapter mounting surface of the gear housing. 16. Install O-Ring (22) in the bearing cap (10) and fasten to gear housing with screws (36). Be sure to re-install the plastic shims between the gear housing and motor adapter. 17. Install worm gear (6) in gear housing with hub down (toward smaller opening). 18. Apply a smooth even coating of Form-a-Gasket® to the top flange of the upper housing. 19. Place the gear housing with assembled parts on top of the upper housing guiding the worm gear keyway over the key (20) in the upper stem and fasten to the upper housing with capscrews (38). 20. Install ball bearing (27) over upper stem and secure with upper stem nut. 21. Install insert and set screw into upper stem nut. 22. Fill the gear housing with grease up to the top of the worm gear. 23. Apply a smooth even coating of Form-a-Gasket® around top surface of the gear housing. 24. Install the grease seal (26) in the gear housing cover (8). Slide the cover over the indicator shaft (12) and ball bearing (27) and secure to the top of the gear housing with capscrews (35). 25. Install stem protector (24) and secure indicator flag (11) in place with set screw (39). Installation, Operation and Maintenance Manual 28 07/2011 / IOM-GEN-TWIN-03 ENGINEERED & PROCESS VALVES UNDERSTANDING THE DIFFERENTIAL THERMAL RELIEF BLEED SYSTEM SCOPE This specification addresses the proper functioning, trouble shooting, and repair of the GENERAL VALVE TWIN SEAL differential (pressure) thermal relief (DTR) bleed system. BACKGROUND HOW IT WORKS When the Twin Seal valve is seated and completely filled with a liquid, any slight variation in temperature due to the sun’s rays or ambient thermal fluctuations will cause significant changes in body cavity pressure resulting from thermal expansion. The Differential (pressure) Thermal Relief (DTR) system is arranged as shown below. A variety of components are used in the DTR. As shown below, one can see that the relief valve mounted at the tee outlet on the bonnet pressurizes the upstream throat of the valve. The standard relief valve is set to open at 25 psi on all valves regardless of working pressure. With the valve closed, the relief valve will open at 25 psi above upstream pressure. This system functions only when the valve is closed. Valves filled with 330 API fuel oil have exhibited a 75 psi increase in pressure with a temperature rise of only 1°F. Putting this into perspective, a normal daily 30°F swing in ambient temperature may cause an increase of body cavity pressure of 2250 psi. While results vary under actual service conditions depending on media, pressure vessel rigidity, and presence of entraned gas it is known that dangerously high pressures will build up in liquid filled positive shut-off valves. Therefore, the Twin Seal in liquid service requires a pressure relief device. The Differential (pressure) Thermal Relief (DTR) system is one such automatic “device” and should be included on every automated valve. A manual body bleed valve is included on the Twin Seal as standard. This bleed valve installed in the relief system is openedafter the Twin Seal is closed. Seal effectiveness can be immediately evaluated, after allowing a few seconds for stabilization of cavity volume due to entrained air or gas. The bleed valve must be closed before the Twin Seal is reopened. An isolation valve installed in the upstream throat tap is also included on the standard DTR. It must be left open to permit relief system to relieve pressure upstream. The isolation valve will be used only for maintenance and trouble shooting which will be explained later. Valve is to be CLOSED ONLY FOR REPAIR. If closed during normal operation the automatic portion of the relief system (relief/check valve) will be defeated. (The outlet of the relief valve would close when closing the isolation valve). The remaining components of the bleed system i.e., tube fittings, nipples, pipe fittings etc., are not functionally involved in “how it works” but may be involved in “why it doesn’t work” which will be discussed later. MODELS 400/800/900 RELIEF VALVE BODY CAVITY TAP MODELS 8800 TEE MANUAL BLEED BLEED HOLE located in bonnet on all valves except as noted below ISOLATION VALVE ISOLATION VALVE UPSTREAM THROAT TAP SAFETY CHECK INTEGRAL CONTAINING RELIEF AND MANUAL BLEED VALVES DOWNSTREAM THROAT TAP Manual bleed with differential thermal relief (DTR) system discharged to flow line 07/2011 / IOM-GEN-TWIN-03 29 Installation, Operation and Maintenance Manual ENGINEERED & PROCESS VALVES WHY IT IS ESPECIALLY IMPORTANT ON MOTOR OPERATED VALVES Electrically powered actuators or motor operators are configured normally to bypass or ignore the opening torque limiter as the valve just begins unseating. UNSEATING CONTINUES SLIPS RETRACT SUFFICIENTLY FAR TO DISLODGE SEALS FROM BODY If the motor operated Twin Seal has experienced any thermal expansion, the pressure in the body cavity may have increased significantly above line pressure (see figure below) which would hydrostatically cause unseat load resistance. If these slips are pulled inwardly by the ascending plug, the trapped body cavity volume is squeezed. PRESSURE EQUALIZES PRESSURE BUILDS AS A RESULT OF THERMAL EXPANSION OF A TRAPPED VOLUME OF LIQUID LINE PRESSURED INDEPENDENT OF BODY CAVITY PRESSURE UNSEATING BEGINS SLIPS RETRACT “SQUEEZING” THE TRAPPED VOLUME AND THUS ADDING TO THE CAVITY PRESSURE CONCERNS OF OTHER TYPES OF ACTUATORS Other remotely power operated valves, i.e. hydraulic, pneumatic, DC, etc., may display stall problems during unseat if no automatic pressure protection (DTR) is installed, therefore DTR is required in these applications also, but stall torque does not represent same damaging concern. MANUALLY OPERATED VALVES Manually operated valves (operated locally) allow access to their manual body bleed valves which may be vented slightly to relieve this pumping action as well as thermal build up. If this center cavity cannot be vented to the atmosphere for enviromental or safety reasons, the DTR may be required. Optionally, a manual body bleed alone may be acceptable. Symptom Problem Solution Valve stalls as it unseats Isolation valve closed Open isolation valve - close only to repair LINE PRESSURE REMAINS CONSTANT This pumps the body cavity pressure even higher adding directly to the thermal expansion pressure until something gives, such as... 1) The slip seals retract or 2) The motor stalls or 3) Something breaks or 4) The DTR relieves Since our slip seals are so dependably bubble tight and motor stall may be as high as 6 times maximum rated torque (remember the torque limiter is out of the unseat circuit) we see that electric motor operators MUST have AUTOMATIC pressure protection which is, as shown previously, exactly what the DTR does best. Torque switch settings on electric actuators should be set higher on the opening direction than the closing direction. Installation, Operation and Maintenance Manual Relief check valve Close isolation valve bleed installed backwards and drain valve, remove check/relief reverse reinstall close bleed open isolation valve Tubing/piping leaking Check valve plugged foreign material, loose fittings/nipple damaged bleed Same as above, but replace or clean Close isolation valve, close valve bleed and drain, repair as required, open isolation valve close bleed In order to check that the bleed system works properly, observe the pressure upstream of the valve. Seat the Twin Seal, verify integrity. Hook up a hand pump with proper pressure gauging to the manual body bleed. With the hand pump reservoir full of compatible fluid open MBV, begin pumping slowly observing body cavity pressure. Note it should not exceed upstream pressure by more than 25 psi. If this is so, the DTR relief has been verified. 30 07/2011 / IOM-GEN-TWIN-03 ENGINEERED & PROCESS VALVES OPERATION & MAINTENANCE The Twin Seal valve requires no day-to-day maintenance, however, there are some services which may be needed occasionally. ANNUALLY 1. Drain plugs in the lower plate should be removed and the residue flushed and drained from the lower plate. In cold climates, before freezing weather sets in, any possible collection of water below valve plug or plug trunnion should be drained out through the lower plate drain plugs. SEMI-ANNUALLY a. Keep the valve operator housing full of lubricant to displace and prevent moisture from accumulating and freezing. The operator is provided with a grease fitting. Lubricant should be injected with the Twin Seal valve in the open position only. Under ordinary conditions, a few pumps of the grease gun semi-annually is sufficient. Use lithium 12 hydroxy stearate or lithium base molydisulfide grease. SEMI-ANNUALLY b. If applicable, temporarily remove ABBV cover and guide pin. Liberally apply grease in this area semi-annually. IF AT ANY TIME... 2. If at any time the body bleed should indicate a leak which cannot be stopped with ordinary force on handwheel (no cheaters necessary), this may be corrected by one of the following: a) b) c) 3. If stem packing needs replacement, it can be changed as follows: a) Remove operator as described in #4 below. b) Remove packing gland and replace inner and outer O-Rings and backup ring. c) Remove packing rings and replace carefully. d) Replace packing gland. e) Replace operator as described in #4. 4. To change operator: a) Shut down line pressure. b) Close GENERAL VALVE TWIN SEAL valve extra tightly. c) Open bleed valve for zero pressure when removing operator. d) Drive out coupling pin (towards guide pin boss). e) Remove housing mounting bolts and lift operator off. f) Replace new operator in reverse order (insert coupling pin from same side as guide pin boss.) g) Close bleed valve. h) Check operation of valve. PARTS Operate valve through open-close cycle while fluid is flowing to flush out valve body. After several flushing attempts, close the Twin Seal valve and check body bleed again. If body bleed still indicates valve leakage, proceed to b). If the valve is supplied with a DTR system, it is possible that the relief valve may be leaking. Check this by temporarily closing the line isolation valve. If the leak stops, repair or replace the relief valve. If this is not the case, the slips need inspection. To inspect or replace slips the line must be drained. Then place the Twin Seal valve in the open position (check body bleed valve for zero line pressure) and remove lower plate (lower plate can be driven off by closing valve, inserting a wedge and then opening valve again). Slips can be removed from plug and inspected or replaced if damaged. Be sure to save the old slips and return to Cameron for exchange credit. It is recommended to replace the lower plate O-Ring and gasket any time the lower plate is removed and slips are replaced. 07/2011 / IOM-GEN-TWIN-03 If the lower plate is not accessible for replacing seating slips, the valve operator and bonnet can be removed (Check body bleed for zero line pressure before removing bonnet) and slips replaced from the top of the valve. 31 Cameron’s Valves & Measurement group provide only new factory replacement parts which are supplied through the local Cameron Sales Office, details of which can be found at www.c-a-m.com. O-Rings, gland packing and gaskets are packaged into kits that make ordering simple. Be sure to specify valve size, series, part number from the slip and type of resilient seal material when ordering replacement slips. Ask about Cameron’s Slip Exchange Program Cameron, through CAMSERV Aftermarket Services also offers remanufactured valves, emergency repairs, technical assistance, maintenance contracts, commissioning and service training seminars. Installation, Operation and Maintenance Manual ENGINEERED & PROCESS VALVES TRADEMARK INFORMATION GENERAL VALVE® is a registered trademark which is owned by Cameron. This document contains references to registered trademarks or product designations, which are not owned by Cameron. Trademark Owner Form-a-Gasket Permatex Installation, Operation and Maintenance Manual 32 07/2011 / IOM-GEN-TWIN-03 ENGINEERED & PROCESS VALVES 07/2011 / IOM-GEN-TWIN-03 33 Installation, Operation and Maintenance Manual ENGINEERED & PROCESS VALVES VALVES & MEASUREMENT 3250 Briarpark Drive, Suite 300 Houston, TX 77042 USA Toll 800 323 9160 For the most current contact and location information go to: www.c-a-m.com Installation, Operation and Maintenance Manual 07/2011 / IOM-GEN-TWIN-03
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