Troubleshooting Guide For Low Power; Relief Valve Checks - NPK M20S Instruction Manual

TROUBLESHOOTING

TROUBLESHOOTING GUIDE FOR LOW POWER

RELIEF VALVE CHECKS

PROBLEM
Operating Pressure
is less than 3,625
psi (250 bar).
CAUSE
Carrier hydraulic
circuit relief valve.
Material Processor
relief valves
Pilot check valve
assemblies.
Swivel manifold
assembly
CHECK
Measure the carrier
circuit relief valve with
the pressure to close
shut-off valve in the
"OFF" position.
Measure the relief
valves with the shut-
off valves on the
carrier in the "ON"
position. Check
pressure with the
jaws fully open and
fully closed.
Check relief
cartridges for
tightness.
Check relief
cartridges for mis-
adjustment.
Check the o-rings
and backup rings of
the relief valve
cartridges.
Inspect the booster
inlet pilot check
valves for damage.
Check the seals
between the open
and close passages
in the swivel manifold
assembly.
Check the land areas
for the seals in the
swivel manifold
assembly.
- -
129
REMEDY
Adjust or replace the
carrier circuit relief
valve. The setting for
the relief valve must
be 200 psi (14 bar),
minimum, above the
Material Processor
operating pressure.
Setting should be
3,625 psi (250 bar).
Tighten the relief
valve cartridges.
Reset to 3,625 psi
(250 bar). If unable to
adjust, replace the
cartridge.
Replace the o-rings
and backup rings of
both relief valve
cartridges.
Replace the inlet pilot
check valve
assemblies if
necessary.
Replace the seals in
the swivel manifold
assembly.
Repair the land area
or replace the
spindle.