Gate Valve Maintenance & Adjustment Procedures 1 Nor-Cal Products, Inc., 1967 South Oregon St., Yreka, CA 96097 • Toll Free 800-824-4166 or 530-842-4457 • www.n-c.com Rev.
Table of Contents I. GATE AND BONNET O-RING 1.5” - 21” GATE VALVES.................................................................................3 II. BELLOWS, PNEUMATIC STANDARD 1.5” - 21” GATE VALVES....................................................................5 III. ACTUATOR O-RING 1.5” - 21” GATE VALVES..............................................................................................8 IV. SEAL PLATE ASSEMBLY/ PINS BEARING 1.5” - 21” GATE VALVES.................................
I. Viton Gate & Bonnet O-ring STD AND MSB 1.5” - 21” GATE VALVES A. Tools and Materials Required: 1. Allen Wrench for 1.5”—14” Gate Valves 2. 1/2” Box Wrench for 16”—21” Gate Valves 3. O-Ring Pick 4. Rubber Gloves 5. Grease – Apezion L O-Ring Type 6. IPA B. Procedure: Always wear Rubber Gloves when handling the Gate Valve 1. Vent station and pump corresponding to Gate Valve to atmosphere. 2. Actuate valve to Gate Open position. 3. For safety, remove air to actuator. 4.
6. 7. 8. 9. 10. Remove O-Ring or Gasket from Bonnet Assembly and discard. Remove Gate O-Ring with the plastic pick, taking care not to scratch the O-Ring groove. Discard the O-Ring. Clean O-Ring groove with IPA and dry out with Nitrogen or CDA. Apply a light coat of Apezion L grease to the new Gate O-Ring. (It is very important that gloves are worn for this step) Install new O-Ring on gate, taking care to avoid twisting or deforming the O-Ring. 11.
II. Bellows, Pneumatic Standard Cycle Only 1.5” – 21” GATE VALVES A. Tools and Materials Required: 1. Spanner Wrench 2. Allen Wrench Set 3. O-Ring Pick 4. Pick (for R-Ring removal) 5. Needle-Nose Pliers 6. Small Standard Screw Driver 7. Actuator O-Rings 8. Grease for Bellows O-Ring: Apezion L 9. Vacuum Grease 10. IPA 11. Heat Gun 12. Lock-Tite B. Procedure: 1. Vent station and pump corresponding to Gate Valve to atmosphere. 2. Actuate valve to Gate Open position. 3. For safety, remove air to actuator. 4.
INDENTATIONS ON THE PISTON FOR SPANNER WRENCH NOTE: GATE MUST BE IN OPEN POSITION TO ACCESS THESE EASILY JAM NUT NOTE: May require use of the heat gun to melt any LOCK-TITE Figure 4 - PISTON CLOSE-UP FOR SPANNER WRENCH POSITIONING 8. 9. 10. 11. 12. Using a spanner wrench, turn Piston counterclockwise to remove from Actuator Housing. Remove O-Ring from top of Drive Shaft. Remove remaining screws holding the Actuator Housing to the Bonnet Plate. (2 screws) Remove the Actuator Housing.
27. Install Piston on Drive Shaft; using a spanner wrench, turn clockwise until the measurement in step # 5 is achieved. 28. Install Jam Nut, using Lock-Tite and tighten. 29. Install Actuator Top and tighten screws. 30. Install Actuator Cover and tighten screws. 31. Install air line and test operation of Valve and Actuator.
III. Actuator O-ring 1.5” – 21” GATE VALVES STD AND MSB A. Tools and Materials Required: 1. Spanner Wrench 2. Allen Wrench Set 3. O-Ring Pick 4. Pick (for R-Ring removal) 5. Needle-Nose Pliers 6. Small Standard Screw Driver 7. Actuator O-Rings 8. Grease for Bellows O-Ring: Apezion L 9. Vacuum Grease 10. IPA 11. Heat Gun 12. Lock-Tite B. Procedure: 1. Actuate valve to Gate Open position. 2. For safety, remove air to actuator. 3. Remove Actuator Cover. (2 screws) 4. Remove Actuator Top. (6 screws) 5.
. Remove remaining screws holding the Actuator Housing to the Bonnet Plate. (2 screws) 10. Remove the Actuator Housing. 11. Remove O-Ring in Actuator Housing, using a pick and using care to not scratch the groove surface. ACTUATOR O-RING NOTE: 1. REMOVE THIS O-RING BEFORE REMOVING THE ACTUATOR HOUSING Figure 3: ACTUATOR O-RING 2. BE CAREFUL NOT TO SCRATCH THE O-RING GROOVE 12. Apply a thin coat of vacuum grease on the new O-Ring. 13 Install O-Ring. 14.
IV. Seal Plate Assembly / Pins Bearing 1.5”—21” A. Tools and Materials Required: 1. Allen Wrench Set 2. Arbor Press 3. Punch 4. Hammer 5. Wrenches (Box or Open) 6. R-R Pliers 7. Vacuum Grease 8. IPA 9. Latex Gloves B. Procedure 4” – 21” 1. Actuate valve to gate Open position. 2. For safety, remove air to actuator. 3. Remove bolts that hold Bonnet Actuator Assembly to body. For Quick-Clamp Bonnet, undo the clamp. 4. Pull out the Bonnet Actuator Carriage Assembly. 5.
6. 7. Separate the Bonnet Upper Linkage Assembly from the Carriage Assembly. Measure the distance between the Strongback Lower Linkage and the Upper. Linkage-Lower Linkage. (This will be helpful later during reassembly and valve adjustment) Figure 5: PIN AND LINKAGE CLOSE-UP PIN (HOLDS UPPER AND LOWER LINKAGES DIMENSION “C” NOTE: IF PIN DOESN’T COME OUT EASILY, FLIP OVER AND HIT WITH PUNCH ON THE OTHER SIDE 8.
13. Using a punch and hammer, remove wheels from their pin. Note: If the pin does not move, try from the other side. 14. Using an arbor press, remove the bearings from the links and wheels; Discard expendable parts; 15. Clean all reusable parts such as the gate, Strongback, Links, Carriage Bars, and Gate Spring with IPA; 16.
Figure 12: GATE AND STRONGBACK ASSEMBLY AFTER REASSEMBLY AFTER REASSEMBLY, CHECK THAT THE GATE ASSEMBLY SITS FLUSH ON THE STRONGBACK AND MOVES FREELY UP AND DOWN. DO THIS BEFORE INSTALLING THE GATE SPRING. 31. 32. 33. 34. Verify the measurement in step # 7, and adjust as necessary Tighten bolts or install Quick-Clamp as appropriate Test Valve operation If necessary, refer to Valve Adjustment Procedure Figure 13: STRONGBACK & GATE ASSEMBLY DRAWING 13 Nor-Cal Products, Inc., 1967 South Oregon St.
V. Valve Adjustment COMPRESSION AND OVER-CENTER 1.5” – 21” A. Tools and Materials required: 1. Allen Wrench Set 2. Wrench Set (Box and Open) 3. Air Regulator 4. Heat Gun 5. Latex Gloves B. Procedure: Steps 1 through 8 apply to 1.5” and 3” Gate Valves only. 1. Actuate Valve to Open Gate position. 2. For safety, remove air from Actuator. 3. Remove Actuator Cover (2 screws) 4. Remove Actuator Top (6 screws) 5. Loose Jam Nut on Drive Shaft.
Valve Adjustment Chart INSTRUCTION FOR VALVE ADJUSTMENT VALVE DIMENSION “A” SIZE PISTON ADJUST* DIMENSION “B” OVERCENTER ADJUST 1.50 .110 ** 2.00 .120 ** 2.50 .125 ** 3.00 .125 ** 4.00 N/A 6.00 N/A 8.00 N/A 10.00 N/A 10.75 N/A 12.00 N/A 14.00 N/A 16.00 N/A 18.00 N/A 21.00 N/A N/A N/A N/A N/A .278 .085 .365 .770 .635 .640 — .540 — — DIMENSION “B” NO OVERCENTER ADJUST N/A N/A N/A N/A .360 .160 .465 .800 1.035 1.035 — .760 — — DIMENSION “C” COMPRESSION ADJUST RECOMMENDED LOCKING AIR PRESSURE .
Figure 16 PNEUMATIC ACTUATOR ASSEMBLY 16 Nor-Cal Products, Inc., 1967 South Oregon St., Yreka, CA 96097 • Toll Free 800-824-4166 or 530-842-4457 • www.n-c.com Rev.
