Consolidated 1511 Series Safety Valve Instruction Manual
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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
percent 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 9.
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.
5 When presetting is complete, remove the gag and
replace the cap and lifting lever assembly. Attach a
rope to the lever and stand by to hold the valve open
if necessary. Now the valve is ready to test.
6. Increase the boiler pressure at a rate not to exceed
2 psig (0.14 barg) per second. Note and record the
pressure indicated on the pressure gauge when the
valve pops open. After the valve pops open, reduce
the fire in the boiler and lower the pressure until the
valve closes. Note and record the pressure when the
valve closes.
7. Determine if the valve popping point and reseating
point comply with the ASME requirements.
a. If the valve operation meets the appropriate
standard, raise the pressure in the boiler and
conduct two more verification tests.
b. If in raising the boiler pressure, the valve does
not pop open within 3 percent overpressure
(for ASME Section I valves), or 10 percent
overpressure (for ASME Section VIII valves),
reduce the fire in the boiler and pull the rope to
open the valve. Release the rope and allow the
valve to close when the boiler pressure returns
to operating level. Allow the boiler to reduce to
approximately 85 percent of the set pressure.
Remove the cap and lifting lever assembly
from the valve, and turn the compression screw
lock nut counter-clockwise (as viewed from the
top of the valve) until it moves freely. Reduce
the compression in the spring by turning the
adjusting screw counter clockwise one turn
(as viewed from the top of the valve). Replace
the cap and lifting lever and retest the valve.
Continue repeating this procedure until the valve
opens at, or below, the set pressure recorded on
the nameplate.
XIII. Reassembly (Cont’d)
A. Steam Testing Procedures
XIV. Setting and Testing
6. Thread the compression screw into the yoke,
reestablish the original relationship between
compression screw and spindle, as measured in
Section X, Disassembly of 1511 Series Safety Valve,
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, as measured in
Section X, Disassembly of 1511 Series Safety Valve,
step 2. 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” (3.18 mm) to .063” (1.59 mm)
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.
