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單項選擇題

Hydraulic control check value is generally used to （） in the marine hydraulic mechanism.

A.control the back pressure of return oil
B.lock the oil lines under some conditions
C.change the direction of oil flow
D.act as relief valve

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單項選擇題

Check value is used to control （）

A.direction of oil flow
B.back pressure of return oil
C.bypass of filter
D.high pressure overflow

單項選擇題

（）can cause oil flow from sludge outlet of self cleaning separator.

A.Too much sludge accumulated in separator bowl
B.Diameter of gravity disc too large
C.High level tank lack of water
D.Oil input too rapidly