Consolidated 1811 Series Safety Valve Instruction Manual
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© 2020 Baker Hughes Company. All rights reserved.
During reassembly, three items are of extreme
importance. They are:
1) Alignment
2) Cleanliness
3) Lubrication
To achieve the correct alignment, the bearing surfaces
of the compression screw/upper spring washer,
spindle/lower spring washer and spindle to disc pocket
should each be ground together to attain a perfect
match. This is done by applying a lapping and grinding
compound of about 500grit on one of the surfaces and
rubbing them together until a smooth unbroken contact
point is established on both surfaces.
All bearing surfaces and threaded areas must be
lubricated using a high quality high temperature
lubricant. At the factory, nickel-ease is used and is
recommended. For environments where corrosion is a
problem, contact the factory field service department
for suggestions on special coating or plating
procedures which will protect the parts.
1. Thread the lower ring onto the seat bushing and
turn it down until it is below the seating surface.
(This allows the disc to rest on the bushing without
interference from the ring).
2. Thread the upper ring/guide into the valve body
reestablishing its original relationship to the
bushing, as measured in Disassembly, Step 2.
Insert the upper adjusting ring pin into the valve
and tighten. The ring should now be able to rock
back and forth but not turn. If position is not known,
refer to Section XII.
3. After inspecting both the disc and bushing seat for
cleanliness, thread the spindle into the disc and
insert the disc gently into the valve until it rests on
the bushing.
4. Place the spring and spring washer into the yoke.
5. Place the yoke over the spindle and replace the
cap screws or nuts. Care must be taken to tighten
the yoke down evenly to prevent distortion and
misalignment.
6. Thread the compression screw into the yoke,
reestablish the original relationship between
compression screw and spindle, as measured in
disassembly, Step 6. Then tighten the compression
screw lock nut.
7. Raise the lower ring until it contacts the disc
then lower it the number of notches needed to
reestablish its original relationship to the disc.
Thread the lower adjusting ring pin into the body
and tighten. The ring should be free to rock back
and forth but not turn. If position is not known, refer
to Section XIV.C.
8. Thread the release nut onto the spindle and
replace the cap, lever and lever pin. Adjust the
release nut so there is from .125” (3.18mm) to
0.063” (1.59mm)clearance between the release
nut and lever. Remove the lever pin, lever and
cap, replace the lock nut or cotter pin, and tighten
it against the release nut. Replace the cap, lever,
lever pin and cotter pin and tighten the set screw.
The valve is now ready for setting and testing.
XIII. Reassembly of 1811 Series Safety Valve
1. Remove the caps on all valves to be set on the
steam drum and main steam line, or other pressure
vessel.
2. Install a “verified calibrated” pressure gauge on
the drum near the valves being set. When the
main steam line valves are to be set, install the
calibrated gauge to read line pressure upstream of
the valves to be tested.
3. After the pressure in the boiler has increased to
80% of the operating pressure, install gags on all
valves except the high set valve. Gags should be
installed hand tight (no wrenches or mechanical
force).
4. Examine the nameplate on the high set valve. The
symbol that is present on the nameplate will indicate
the proper standard of operation, as described in
Table 8.
During reassembly, the adjusting rings and
compression screw should be reset as they
were prior to disassembly.
If the correct adjusting
rings positions are not known, the adjusting rings
should be preset according to instructions in
Section XIV.C.
Before attempting to make ring adjustments on a
valve under pressure,
gag the valve.
XIV. Setting and Testing
A. Steam Testing Procedures
