单项选择题
A.tend to twist about its long axis B.expand in length and in diameter C.contract in length and expand in diameter D.flex at right angles to the applied pressure
An air compressor can be unloaded at start-up by （）.A.h...
单项选择题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
Machinery driving fuel oil transfer and fuel oil servic...
单项选择题Machinery driving fuel oil transfer and fuel oil service pumps must be fitted with a remote means of stopping the machinery from （）.
A.within the space concerned B.outside the space concerned C.the throttle station D.within the fire room
If an electric motor driven air compressor fails to sta...
单项选择题If an electric motor driven air compressor fails to start, it may be due to a （）.
A.leaking discharge valve B.jammed suction valve C.tripped overload relay D.broken discharge un-loader
