单项选择题

An un-loader is installed on an air compressor to （）.

A.bypass the high pressure stage to the low pressure stage on 100% of the air compressors in service
B.prevent excessive inter-stage pressure buildup
C.control compressor discharge pressure
D.remove all but the frictional load during starting

相关考题

After installing a new hydraulic pump in a system, what...

单项选择题After installing a new hydraulic pump in a system, what special attention should be given to the hydraulic system?（）

A.The relief valves in the system should be readjusted
B.The filters and strainers should be checked frequently
C.All system pressure should be readjusted
D.The system should be drained and renewed with a fluid of different operating characteristics

For safe storage, the maximum allowable temperature to ...

单项选择题For safe storage, the maximum allowable temperature to which refrigerant bottles should be exposed is （）.

A.100℃
B.125℃
C.150℃
D.175℃

One of the main functions of wearing rings, as used in ...

单项选择题One of the main functions of wearing rings, as used in a centrifugal pump, is to （）.

A.maintain radial alignment between the pump impeller and casing
B.absorb all impeller shaft end thrust
C.prevent water leakage to the atmosphere
D.prevent wear of the pump casing and/or impeller

船舶辅助机械

An un-loader is installed on an air compressor to （）.