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单选题
An air compressor can be unloaded at start-up by （）.
A
holding the discharge valve open
B
relieving the intercooler pressure to the atmosphere
C
using an enlarged, permanently opened clearance expansion space
D
a pre-charged accumulator
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单选题Before starting an air compressor, It should be （）.A
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air cylinderB
combustion chamberC
steam drumD
expansion tank
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engine cylinderB
air bottleC
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condenser
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outlet pipeC
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单选题An air compressor can be unloaded at start-up by （）.A
holding the discharge valve openB
relieving the intercooler pressure to the atmosphereC
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单选题The loss of （） from an air compressor could lead to an overheated air discharge and possibly an explosion in the pipelines leading to the air reservoir.A
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