Data Sheet

GX Control Valve and Actuator
D103171X012
Product Bulletin
51.1:GX
March 2012
15
The Fisher GX Diaphragm
Actuator
Figure 14. Fisher GX Actuator
W8487-3
The GX uses a multi-spring, pneumatic diaphragm
actuator (see figure 14). It is capable of air supply
pressures to 6.0 barg (87 psig), allowing valve shutoff
at high pressure drops.
The GX product selection system automatically
matches the actuator to the valve, eliminating the
need for complex actuator sizing procedures.
The multiple spring design provides the preload,
eliminating the need for bench set adjustm ent. The
actuator is available in spring-to-open and fail-down
configurations.
TheGXactuatorcanbeusedforthrottlingoron-off
service.
The GX is available with the integrated DVC2000
digital valve controller. Other digital and analog
positioners are available, as well as optional solenoids
and limit switches.
Table 10. Actuator Specifications
Description Pneumatic spring-return diaphragm actuator
Operating Principle
Air-to-open (standard)
Air-to-close (optional)
Operating Pressure Ranges 2.0to6.0barg(29to87psig)
(1)
Ambient Temperature -46 to 82_C (-50 to 180_F)
Pressure Connection (Fail-up Construction) G 1/4 female casing connection
Finish Powder coat polyester
1. May v ary depending on construction (see bulletin 51.1:GX(S1))
Table 11. Materials of Construction
Part Material
Upper and Lower Casings AISI 1010 stamped carbon steel
Springs Steel
Diaphragm Nitrile and nylon
Diaphragm Plate
Size 225 and 750: AISI G10100 stamped carbon steel
Size 1200: Cast carbon steel
Yoke Carbon steel (stainless steel optional for some sizes)
Casing Fasteners A2-70 stainless steel bolts and nuts
Actuator Rod Stainless steel
Stem Connector CF3M
Stem Connector Fasteners SA193-B7 bolts with NCF2 coating
Stem Bushing High-density polyethylene (HDPE)
Stem Seal Nitrile