Instruction Manual

November 2008

GX 3-way Control Valve and Actuator System - 14722 GX 3-Way Valve and Actuator

If the bonnet (key 4) together with the valve stemplug assembly has a tendency to lift with theactuator yoke, ensure it does not drop from the actuator.8. Remove the stem adjustor nut (key 27) andlocknut (key 28).9. Remove the bonnet and the valve plug/stemassembly and set on a protective surface.10. Remove the valve/yoke gasket (key 5) andcover the opening of the valve to protect the gasketsurface and prevent foreign matter from getting intothe valve cavity.11. Remove the packing follower (key 29) from thebonnet (key 4).12. Remove the Belleville spring pack (key 34) andpacking spacer (key 30) from the bonnet (key 4). Carefully push out the remaining packing box partsfrom the bonnet (key 4) using a rounded rod or othertool which will not scratch the packing box wall. Clean the packing box and the metal packing boxparts.

Table 4. Packing Follower Torque

15. Install a new O-ring (key 81) in the groove onthe bottom of the side-port common bonnet (key 4).See figure 10.16. Carefully install the bonnet (key 4) onto thevalve stem.17. Install the new packing and the metal packingbox parts according to figure 7 for PTFE packing andaccording to figure 8 for Graphite ULF packing.Place a smooth-edged pipe over the valve stem and gently tap each soft packing part into the packingbox. Apply anti-seize lubricant to the threads andinstall the packing follower (key 29).18. Install the locknut (key 28) and stem adjustornut (key 27). Install the valve plug/bonnet subassembly into the valve body (key 1).19. Mount the actuator onto the valve and install thebody nuts (figure 9 key 7), but tighten them only finger-tight.20. For fail-down constructions, connect aseparate air supply to the lower diaphragm casingair supply connection (as shown in figure 12) and apply sufficient air pressure to raise the actuator rod(key 22) to the travel stop. Proceed to the next step. For fail-up constructions, proceed to the next step.21. Tighten the valve body nuts (key 7) evenly usinga cross-tightening procedure. See table 3 for torquerequirements.22. Thread the stem adjustor nut (key 27) up tomatch the gap setting between the actuator rod and stem adjustor nut specified in table 2. Thread thelocknut (key 28) up against the stem locknut and tighten to a torque of 47.7 N

CAUTION

m (35.2 lbf ft) for 10mmstems or 175 N Inspect the valve stem, threads and packing box surfaces for any sharpedges that might cut the packing. Scratches or burrs could causepacking box leakage or damage thenew packing. m (129 lbf ft) for 14mm stems.23. Stroke the actuator rod until it contacts the stemadjuster nut (key 27) and install the stem connectorhalves and travel indicator (keys 23, 24, and 26) with the cap screws (key 25). Install the stem connectorhalves in the proper orientation so that when lookingat the inside of the stem connector halves, the flats are down and the beveled surfaces are up. 13. Inspect the valve stem, threads and packing boxsurfaces for any sharp edges that might cut thepacking. Scratches or burrs could cause packing boxleakage or damage the new packing. If the surface condition cannot be improved by light sanding,replace the damaged parts.14. Remove the covering protecting the valve cavity and install a new valve/yoke gasket (key 5)making sure that the gasket seating surfaces are clean and smooth.