Baker Hughes Linear Piston Spring Return Actuators

1. Apply 100 psig power supply gas to the cylinder top port and ZERO pressure to the cylinder bottom port.

2. Remove the tubing fitting (and pneumatic buffer or desiccant canister) from the actuator cylinder bottom port.

3. Check for excessive piston seal leakage at the ZERO pressure port.

4. Apply 100 psig power gas supply to the cylinder bottom port and ZERO pressure to the cylinder top port.

5. Remove the tubing fitting from the actuator cylinder top port.

6. Check for excessive piston seal leakage at ZERO pressure port.;

1. Remove the pneumatic buffer system or desiccant canister. 2. Pressurize the normally pressurized side of the cylinder with at least 100 psig power supply gas. 3. Apply a leak-check solution around the perimeter of the cylinder tubing wall. Any leakage should be easily visible. 4. Follow procedure 5 on page 13 to replace tube seals.

1. For pneumatic buffer system, check for leaks around the check valve and up to the cylinder port to ensure the system is working.

2. For vent breather, replace the unit at the first signs of moisture inside the canister. For a working regulator, it is recommended to replace the cartridge annually. The replacement part number is 22-2542.

3. When additional accessories are used (MCV, Versa Valves, etc.) all parts must be connected through the check valve.;

1. Remove the power gas to allow the actuator cylinder (A) to stroke to the spring position.

2. Depressurize all instrumentation.

3. Remove instrumentation tubing and instrumentation from the actuator cylinder (A).

4. Make a vertical reference mark between bottom mounting flange (B) and cylinder tube (C) to ensure proper realignment upon reassembly.

5. Remove tie rod nuts (D) from top flange (E). If tie rod nut (D) seizes and tie rod (F) unscrews, remove entire tie rod (F).

6. Remove tie rods (F), then remove top flange (E) and top seal O-ring (G).

7. Remove cylinder tube (C) and bottom seal O-ring (H) from bottom mounting flange (B).

8. Remove top piston U-cup (I) and bottom piston U-cup (J) from piston (K).

9. Remove any rust, dirt, or foreign material from cylinder tube (C) wall and piston (K) using solvent if needed.

1. Fully pressurize "rod" side of actuator cylinder.

2. Ensure both block valves are closed.

3. Observe gauge needle opposite from "rod" side of cylinder; if gauge needle moves, then piston seals (u-cups) may need replacement.

5. Observe gauge needle on "rod" side of cylinder. If needle shows a decrease in pressure, piston rod seals must be replaced. Follow procedure 6 on page 15 to replace piston rod seals.;