Flowserve 1888 Parallel Slide Gate Valve - Manual (Page 7)

9.0 MAINTENANCE INSTRUCTIONS
9.1 The following instructions cover the disassembly and reassembly of a gate
valve. Typical valve configuration is shown in Figure 1 (see Section 12.0).
CAUTION
CHECK LINE PRESSURE: IF LINE IS STILL UNDER PRESSURE,
VENT BEFORE VALVE DISASSEMBLY IS STARTED
9.1.1 Disassembly
Extreme care should be taken to ensure that the stem and discs do
not separate when removed as one unit, until both are adequately
supported. Failure to do so may cause damage to the disc.
After removal from the valve, care should be taken to protect the
seating surface of the discs from damage. The discs should be
placed in a clean area until they are ready to be replaced in the
valve. THE SLIGHTEST NICK OR SCRATCH ON A SEATING
SURFACE MAY PREVENT COMPLETE SHUT-OFF AND
NECESSITATE EXTENSIVE REWORK OR REPLACEMENT.
(a) Place the valve in the closed position and open about one-
half (1/2) of a revolution of the Tee handle.
(b) Remove the handwheel nut (240) from the yoke sleeve (017).
(c) Remove the tee handle (175) and thrust washer (147) from
the yoke sleeve (017) by sliding it up and over the yoke
sleeve.
(d) Remove the yoke clamp nut (233) allowing removal of the
yoke capscrew (217).
(e) Rotate the yoke (011) in a counterclockwise direction to
remove the body (001) and slide it up and over the yoke
sleeve.
(f) Turn the yoke sleeve (017) off the stem (025).
(g) Remove the gland stud nuts (234), allowing removal of the
gland bolts (210).
(h) Lift the flange gland (133) upward and remove the packing
(110,112) from