Consolidated 2700 Series Safety Valve Instruction Manual
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© 2022 Baker Hughes Company. All rights reserved.
XV. Setting and Testing (Cont.)
The hydrostatic plugs are placed in the bore of the
valve, inside the seating surface. Their purpose is
twofold. First, they effect closure at a point differing
from the seating surface of the valve so that, if the
valve is lifted on hydrostatic test, the seating surface
is not as likely to be damaged. Second, by raising
the disc of the valve off its seat and increasing
spring compression, the set pressure of the valve is
increased to a point where the valve will not leak at
one and one-half times design boiler pressure. It is not
necessary to gag the safety valves when hydrostatic
plugs are used.
DRAIN
SERVICE
PLUG
HYDRO PLUG
CAUTION
DO NOT STEAM TEST
UNTIL THE PLUG
HAS BEEN
REMOVED
This safety valve is
equipped with an
internal plug for
hydrostatic test
D
O
N
O
T
R
E
M
O
VE
TH
IS TAG UNTIL
PL
UG
IS
R
E
M
O
V
E
D
Figure 17: Hydrostatic Test Plug
These plugs must, of course, be removed from the
valves prior to placing the boiler in service. However,
they should be retained, and reinstalled, whenever a
hydrostatic test is conducted that exceeds the low set
valve pressure.
Before starting to disassemble the valve, be sure that
there is no steam pressure in the drum or header.