A.The pump delivers full capacity when started, but gradually slackens off toan abnormally low flow
B.The pump packing gland overheats after short operating periods
C.The motor over-current protective device continually shuts the pump down
D.Pounding noises can be heard at the pump suction chest
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A.diameter of the discharge piping, with all other factors remaining the same
B.diameter of the suction piping, with all other factors remaining the same
C.width of the impeller only
D.diameter of the impeller
A.run continuously
B.not start
C.have high discharge pressure
D.short cycle on the high pressure switch
A.Electrical energy
B.Thermal energy
C.Potential energy
D.Kinetic energy
A.sliding block
B.pintle
C.reaction ring
D.tilting box or swash plate
A.overfeeding of the expansion valve
B.damage to the condenser
C.constant running of the compressor
D.flooding of the receiver
最新試題
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The major source of chemical contaminants in hydraulic fluid is （）.
When the steering gear is in operation, you should （）.
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The usual symptoms of cavitation in a centrifugal pump is （）.
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