Pressure Intensifier Sequence Valve And Relief Valve Actuation - NPK M20S Instruction Manual

TROUBLESHOOTING
2. MATERIAL PROCESSOR RELIEF VALVE
After the Material Processor hydraulic circuit has been verified, check the Material
Processor relief valve settings for both open and close.
A. With a 0 – 5000 psi (350 bar) gauge installed in both the open and close side of
the stick, open the shut-off valves.
B. Start the carrier. Set the throttle at full RPM and close the jaws completely and
hold for 10 seconds. Check the psi (bar) reading on the gauge and compare to
the specified Material Processor relief valve setting. If it is not the same, reset
the Material Processor relief valve accordingly.
C. The booster will start to click. Depending on oil temperature, the booster will
continue to click slowly compensating internal leaking in the main cylinder. This
is normal.
D. If the intensifier is clicking rapidly, pressure may not reach the relief valve setting
due to severe intensifier or cylinder leakage.
E. Open the Material Processor jaws to the fully open position and hold for 10
seconds. Check the pressure reading on the gauge and compare to the
specified Material Processor relief valve setting. If it is not the same, reset the
Material Processor relief valve accordingly.
PRESSURE INTENSIFIER SEQUENCE VALVE AND RELIEF
VALVE ACTUATION
Close the jaws without material in them. When the jaw cylinders are fully stroked, the
load pressure (pr) rises until it reaches the sequence valve setting (P1). The oil is then
diverted to the pressure intensifier. The load pressure momentarily (mo) levels off for
one to two seconds (ti) at the sequence valve pressure setting then rises to the Material
Processor relief valve setting (P2). The carrier relief valve (P3) acts only as a safety
relief and must be set 200 psi (14 bar) above the Material Processor relief setting.
NOTE: Do not adjust sequence valve cartridge (factory preset).
P1
SEQUENCE VALVE SETTING
P2
CRUSHER RELIEF VALVE SETTING
P3 CARRIER RELIEF VALVE SETTING
pr
pressure (psi/bar)
mo
momentarily
ti
time (1 - 2 seconds)
- -
133