Valve Assembly Testing - Emerson Anderson Greenwood Type 443 Installation And Maintenance Instructions Manual

Anderson Greenwood SerieS 400 PiSton Pilot PoPrV
InstallatIon and MaIntenance InstructIons

5 vAlve AsseMbly testinG

5.1 General
the complete valve assembly should be tested
for internal and external leakage and to verify
set pressure using a test set-up similar to that
shown in Figures 10, 11, or 12. the test media
should be air.
CAution
Do not test liquid service valves using water or
other liquid test media. Liquid service valves
should be tested using air as the test media in
accordance with the procedures described below.
Testing fully assembled liquid service valves
using air ensures that no water or other liquid will
remain in the main valve dome after final valve
testing
5.2 low pressure leakage check
note
For valve with iso-Dome pilot, apply regulator supply
pressure equal to a minimum of 200 psi greater than
92% of set pressure.
5.2.1 Valve for gas service or valve with
Iso-Dome pilot
Slowly increase the supply pressure to 30%
of set pressure. Check for main valve nozzle,
seat, and piston seal leakage at the main valve
outlet. to help in seating the valve seat and
piston seal, the valve may be actuated several
times. no leakage shall occur in 15 seconds.
5.2.2 Valve for liquid service
Slowly increase supply pressure to 30% of set
pressure. Check for main valve nozzle, seat,
and piston seal leakage at the main valve
outlet. to help in seating the valve seat and
piston seal, the valve may be actuated several
times. no leakage shall occur in 15 seconds.
if leakage is detected at the valve outlet, note
the leakage in bubbles observed in 15 seconds
and remove the leakage test device from the
outlet flange. With the same supply pressure
applied to the valve inlet, use a bubble test leak
detector to measure leakage through the pilot
exhaust. low pressure leakage performance
is acceptable if the leakage at the main valve
outlet is equal to the pilot exhaust leakage and
this leakage value does not exceed 15 bubbles
in 15 seconds.
liquid service valve with iso-Dome pilot should
be tested per paragraph 5.2.1.
5.3 High pressure leakage check
note
For valve with iso-Dome pilot, apply regulator supply
pressure equal to a minimum of 200 psi greater than
92% of set pressure.
5.3.1 Valve for gas service or valve with Iso-Dome
pilot
Apply supply pressure to the inlet equal to 90%
of the set pressure. Check for leakage at the
main valve outlet. Using a suitable gas and air
leak detector solution, check for leakage at the
cap seal and other pressure connections. no
leakage shall occur at the valve outlet and no
visible leakage shall be detected at the cap seal
or other pressure connections in one minute.
5.3.2 Valve for liquid service
Apply supply pressure to the inlet equal to 90%
of the set pressure. Check for leakage at the
main valve outlet. Using a suitable gas and air
leak detector solution, check for leakage at the
cap seal and other pressure connections. no
leakage shall occur at the valve outlet and no
visible leakage shall be detected at the cap seal
or other pressure connections in one minute.
if leakage is detected at the valve outlet, note
the leakage in bubbles observed in one minute
and remove the leakage test device from the
outlet flange. With the same supply pressure
applied to the valve inlet use a bubble test leak
detector to measure leakage through the pilot
exhaust. High pressure leakage performance
is acceptable if the leakage at the main valve
outlet is equal to the pilot exhaust leakage and
this leakage value does not exceed 60 bubbles
in one minute.
liquid service valve with iso-Dome pilot to be
tested per paragraph 5.3.1.
Where superimposed back pressure is
specified, the downstream or exhaust
connections which are exposed to the back
pressure shall be tested at 1.5 times the
specified back pressure and all mechanical
connections so pressurized will be checked
for leaks. no visible leakage shall occur in
one minute using a suitable gas and air leak
detector solution.
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