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Baker Hughes
© 2022 Baker Hughes Company. All rights reserved.
XV. Setting and Testing (Cont.)
F.2 Hydrostatic Test Plugs
To remove the plug, the following steps must be
followed:
1. Remove the cap assembly, adjust release nut to
the second hole from the top of the spindle and
install cotter pin.
2. Back off the yoke stud nuts uniformly until the
compression screw engages the release nut. Now
remove the yoke stud nuts.
3. Remove the yoke and spring assembly (See
Figure 19), from the base, being careful not to
damage the disc.
4. Remove the hydrostatic test plug from the seat
bushing. To do this, insert a threaded rod into the
tapped hole in the plug and lift up until it is free
from the bushing. Care should be taken not to
damage the seat bushing. Ensure the hydro plug
tag (wired through the drain) is also removed.
5. Remove the disc from the disc holder by turning
clockwise until it is disengaged from the spindle
threads.
Note: Hold the disc holder against the disc
adjusting collar during this step. Otherwise
the disc holder will fall from the spindle
and become damaged.
6. Lap the disc and seat bushing and thoroughly
clean the seats with a clean cloth.
7. Lubricate the spindle tip with “Anti-Seize” and
assemble the disc and disc holder to thr spindle
by turning the disc until the dropout threads
disengage.
8. Reassemble the yoke and spring assembly (See
Figure 19) into the base, being careful not to
damage the disc. Locate the yoke vent to the side
of the valve. The lug on the top spring washer
should be on the right side of the valve when
facing the outlet.
9. Replace the yoke and the stud nuts. Tighten the
stud nuts according to Table 13.
10. Remove the cotter pin from the release nut and
position the release nut so that .125” (3.17 mm) of
Table 13: Yoke Nut Torque Values
Orifice
Designation
Nut Torque
ft-lbs
Nm
1
60
81.35
2
60
81.35
3
110
149.14
5
1
170
230.49
4
1
375
508.43
6
375
508.43
7Q
375
508.43
1. #5 is a smaller orifice than #4.
PLUG
SPINDLE
DISC HOLDER
HYDROPLUG
SEAT BUSHING
Figure 18: Hydrostatic Plug
clearance is visible between the lifting fork and the
release nut, and then install the cotter pin.
11. Install cap and lever assembly.
12. The valve is now ready for the initial field test
on steam in order to check valve set point and
blowdown.