Komatsu PC500LC-10R Shop Manual page 274

COMPONENT PARTS OF HYDRAULIC SYSTEM
OPERATION OF ARM HYDRAULIC DRIFT PREVENTION VALVE OF CONTROL
VALVE
When the arm "OUT" operation is performed
1.
When the arm is operated to "OUT", the pressurized oil from the control valve acts leftward to the right side
of the ring area (S) whose outside diameter is diameter (d1) of the poppet (5) and inside diameter is seat
diameter (d2).
2.
The force acting leftward on area (S) compresses spring (4) and moves poppet (5) to the left.
3.
The pressurized oil from the control valve flows through the opening of poppet (5) to the arm cylinder head.
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10 STRUCTURE AND FUNCTION
PC500LC-10R
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