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单选题
Low pressure air is usually taken through () or pressure regulators to a low pressure reservoir supplying a ring main through driers.
A
globe valves
B
butterfly valves
C
gate valves
D
reducing valves
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单选题Two well-developed high pressure areas may be separated by a().A
Hill of low pressureB
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单选题Compared to a low pressure system,generally the air in a high is().A
warmer,less dense,and less stableB
cool,more dense,and drierC
muggy and cloudyD
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单选题An air mass is termed warm if().A
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单选题Broken valve strips in an operating low pressure, air compressor will cause ().A
an immediate crankcase explosionB
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单选题Each cylinder has one starting valve which is usually opened by air pressure and closed by ()A
nuts and boltsB
new jointsC
spring forceD
sealing rings
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考题
单选题The pressure of pilot air is usually () than that of starting air.A
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lowerC
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考题
单选题Low pressure air is usually taken through () or pressure regulators to a low pressure reservoir supplying a ring main through driers.A
globe valvesB
butterfly valvesC
gate valvesD
reducing valves
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单选题The greater the pressure difference between a high and a low pressure center,the().A
dryer the air mass will beB
cooler the temperature will beC
greater the force of the wind will beD
warmer the temperature will be
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单选题The diurnal variation of pressure is most noticeable().A
above the polar circlesB
in a low pressure areaC
during periods of low temperaturesD
in the doldrums
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单选题麻醉机APL阀的意义()。A
APL是auto pressure lock的简写B
APL是adjustabLe pressure limiting的简写C
APL是air pressure lock的简写D
APL是air pressure lift的简写E
APL是auto pressure lift的简写
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单选题An un-loader is installed on an air compressor to ().A
bypass the high pressure stage to the low pressure stage on 100% of the air compressors in serviceB
prevent excessive inter-stage pressure buildupC
control compressor discharge pressureD
remove all but the frictional load during starting
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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 lowB
the discharge temperature highC
the discharge pressure riseD
the inter-stage pressure low
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low firing pressure and low exhaust temperaturesB
low firing pressure and normal exhaust temperaturesC
high firing pressure and low exhaust temperaturesD
high firing pressure and high exhaust temperatures
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单选题Excessively low air pressure occurring in the intercooler of a reciprocating air compressor is caused by().A
leaky discharge valves on the LP cylinderB
leaky discharge valves on the HP cylinderC
insufficient intercooler coolingD
low ambient air pressure
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