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MAKE-UP VALVE
The make-up valve has the following two functions.
One is to prevent cavitation produced by overrun of the piston motor in order to prevent the overrun
of the upper body. When the motor is turned by the inertia of the upper body to cause the pumping
action, which then causes the motor revolution to rise above the revolution equivalent to the amount
of oil supplied to the motor, the amount of oil equipvalent to the shortage is supplied to the motor
main circuit via the make-up valve from outside to prevent occurrence of vacuum inside the circuit.
The other is a function to add the amount of motor drain and valve leak via the make-up valve to
prevent vacuum inside the circuit to provide the braking capability in the normal circuit status when
a closed circuit is formed between the control valve and the motor as when braking.
4)
Make-up valve
R35Z72SM09
