单选题Air compressors are equipped with unloading systems for the purpose of（）.Aremoving all but the frictional load during startingBrelieving intercoolers of high temperature buildupsCproviding high starting torque in the drive motorDseating valve plates during compressor shutdown
单选题
Air compressors are equipped with unloading systems for the purpose of（）.
A
removing all but the frictional load during starting
B
relieving intercoolers of high temperature buildups
C
providing high starting torque in the drive motor
D
seating valve plates during compressor shutdown
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