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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Bad valves operation of the reciprocating air compressors can be detected by observation of （）.A
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Carbon build up in the piston ring beltB
Faulty operation of a cylinder un-loaderC
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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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