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單項選擇題

The symbol (GB786√1-93) at right side represents （）

A.overflow valve
B.reducing valve
C.relief valve
D.sequence valve

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單項選擇題

The symbol (GB786√1-93) at right side represents （）

A.overflow valve
B.reducing valve
C.relief valve
D.sequence valve

單項選擇題

Overflow valve is used to （）

A.control the fluid flow through it
B.prevent the pressure before it over the specified valve
C.make the pressure after it steady
D.control the direction of oil flow