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單項選擇題

Oil is supplied to the crosshead using a swinging arm or a （） and is sometimes boosted in pressure to and efficient lubrication.

A.telescopic pipe
B.large bore pipe
C.generating pipe
D.central pipe

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單項選擇題

Because of the high loads the bearing material is a tin- aluminum alloy bonded to a steel shellThe crosshead pin is highly polished to a （）.

A.flat surface
B.mirror finish
C.sloping surface
D.inclined surface

單項選擇題

The load on the crosshead pin is always （）, so it is the （）half of the bearing which is subject to wear.

A.upwards；top
B.upwards；bottom
C.downwards；top
D.downwards；bottom