Flowserve 800 Piston Lift Check Valve - Manual (Page 8)

9.0 MAINTENANCE INSTRUCTIONS (Continued)
Pulling of the capscrew (216) will remove the bonnet (002) and pressure
seal gasket (030). Lift out the spring (429) and disc (004).
It may be necessary to insert a wire hook into the holes located in the side
of the disc in order to lift the disc out of the valve.
9.1.2 After removal of the disc from the valve, care should be taken to protect
the seating surface from damage. The disc should be placed in a clean
area until it is ready for replacement. THE SLIGHTEST NICK OR
SCRATCH ON SEATING SURFACE MAY PREVENT COMPLETE
SHUTOFF AND NECESSITATE EXTENSIVE REWORK OR
REPLACEMENT.
9.1.3 Resilient Seat Removal (if so equipped)
To disassemble disc/resilient seat assembly:
a) Remove retaining ring (245)
b) Unscrew disc (004) from disc skirt (005)
Note: For removal, disc skirt should be held by the relieved outside
diameter containing the drainage hole rather than by the outside
diameter guiding surfaces. A slot for a fitted screw driver is
provided at the top of the disc to facilitate removal and to prevent
damage to these critical surfaces.
c) Remove the resilient seat by carefully slipping it over the disc.
CAUTION
DO NOT EXPOSE THE RESILIENT SEAT TO ANY
PETROLEUM BASED OILS OR GREASES OR OTHER
CUTTING FLUIDS, LUBRICANTS, ETC. WHICH
ARE HYDROCARBON BASED.