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单选题
Bad valves operation of the reciprocating air compressors can be detected by observation of （）.
A
the discharge temperature low
B
the discharge temperature high
C
the discharge pressure rise
D
the inter-stage pressure low
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单选题The major difference between the discharge and suction valves installed in most low pressure, reciprocating air compressors is that（）A
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the coolingC
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单选题Which of the following problems would be the probable cause for the faulty operation of a reciprocating air compressor suction valve?（）A
Carbon build up in the piston ring beltB
Faulty operation of a cylinder un-loaderC
Compressor operation in an area of high relative humidityD
Lifting of intercooler rebel valve
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单选题Explosions do occur （） caused by the ignition of oil or vapour gaining access from compressors or defective engine starting valves.A
in boiler drumsB
in refrigerating plantsC
in starting air pipesD
in air coolers
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