Case CX130, Руководство пользователя

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COMPONENTS CX130
CASE TRAINING CENTER
AUGUST 2000
Dipper safety valve
Purpose:
This safety valve is fitted on the rod end arm cylinder. It avoids any uncontrollable movement of the dipper when a
plumbing failure may occur on the piping between the rod end cylinder and the control valve.
Description:
3A Piloted check valve
3B Check valve
3C Spool
3G Relief valve including an anti-cavitation valve
Current operation
Neutral
The cylinder rod pipe is closed by 3B and 3A check valves. The check valve 3A cannot be pushed back because
its spring side is not connected with the tank by 3C spool.
Dipper out
The remote control pressure (5a51) pushes the control valve spool. The oil flows out of the control valve ((5A5
port), enters the safety valve (P1 port), pushes the 3B check valve and goes to the cylinder rod end through the
port P2 directly connected with the cylinder rod end. The oil of the piston end goes to the return through the 5B5
port of the control valve.
Dipper out
The pilot pressure 5b51pushes the control valve spool and the safety valve spool (3C) to the left.
The oil flow supplies the cylinder piston end.
The spring side of the piloted check valve 3A is connected to the tank by the groove of the spool 3C. It's pushed
back and the oil from the cylinder rod end goes to the tank through the metering notches of the spool 3C and the
port 5A5 of the control valve.
Safety operation
If a pipe is broken between the rod end and the control valve the operator can operate the arm in. The movement
speed will be controlled by the metering notches of the spool 3C groove.
Leak specification
P2 to P1+ T1 < 4cc / mn at 9,81Mpa with oil temperature at 50°C
Valve de sécurité de vérin de balancier de CX130