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单选题
Proper lubrication of the main bearings is more easily obtained in a single acting, four-stroke/cycle diesel engine than in a tow-stroke/cycle diesel engine because（）.
A
The direction of pressure on the journal in four-stroke engine is continuously
B
positive feed lubricators are installed on all bearings of four-stroke engine, whereas as a splash feed system is used on tow-stroke engine
C
four-stroke engines usually utilize a heavier grade of oil than tow-stroke engines
D
Low-stroke engines usually consume less lube oil than four-stroke engines
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更多 “单选题Proper lubrication of the main bearings is more easily obtained in a single acting, four-stroke/cycle diesel engine than in a tow-stroke/cycle diesel engine because（）.A The direction of pressure on the journal in four-stroke engine is continuouslyB positive feed lubricators are installed on all bearings of four-stroke engine, whereas as a splash feed system is used on tow-stroke engineC four-stroke engines usually utilize a heavier grade of oil than tow-stroke enginesD Low-stroke engines usually consume less lube oil than four-stroke engines” 相关考题
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Proper lubrication of the main bearings is more easily obtained in a single acting, four-stroke/cycle diesel engine than in a tow-stroke/cycle diesel engine because________.A.The direction of pressure on the journal in four-stroke engine is continuouslyB.positive feed lubricators are installed on all bearings of four-stroke engine, whereas as a splash feed system is used on tow-stroke engineC.four-stroke engines usually utilize a heavier grade of oil than tow-stroke enginesD.Low-stroke engines usually consume less lube oil than four-stroke engines
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单选题In some modern large diesel engines, which of the following is used as the support for the main bearings?（）A
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