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单选题
In order to keep excess oil from the intake ports in two-stroke/cycle diesel engines, （）
A
wide compression rings are used
B
oil rings are located above the piston
C
chromium plating is used on all piston rings
D
oil rings are located near the bottom of the piston skirt
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更多 “单选题In order to keep excess oil from the intake ports in two-stroke/cycle diesel engines, （）A wide compression rings are usedB oil rings are located above the pistonC chromium plating is used on all piston ringsD oil rings are located near the bottom of the piston skirt” 相关考题
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单选题In order to keep excess oil from the intake ports in two-stroke/cycle diesel engines, （）A
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单选题The purpose of the safety relief valves installed on an auxiliary boiler is to （）.A
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reduce excess steam pressure in the boiler
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because ofC
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单选题Which of the following conditions indicates the dilution of diesel engine lube oil by fuel oil?（）A
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Fuel oil discharging from the water outlet of the lube oil purifierC
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单选题We can draw a conclusion from the text that ______.A
oil-price shocks are less shocking nowB
inflation seems irrelevant to oil-price shocksC
energy conservation can keep down the oil pricesD
the price rise of crude leads to the shrinking of heavy industry
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单选题Oil control rings used in two-stroke/cycle diesel engines are located near the bottom of the piston skirt in order to （）A
increase the liner area covered by the oil filmB
maintain an oil film on the lower liner where scuffing is prevalentC
keep excess oil away from intake and exhaust portsD
help cushion piston skirt side thrust by providing a hydrodynamic oil wedge
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单选题Broken intake valve springs on one cylinder of a diesel engine can cause the engine to （）A
Over speedB
fire improperlyC
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overheatrapidly
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单选题Directional intake ports in diesel engines are used to （）.A
reduce air charge turbulenceB
induce air swirlC
deflect hot combustion gas away from the valvesD
oppose the effects of piston induced squish
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单选题In order to benefit from the use of storm oil in heavy seas，the storm oil should be spread （）.A
around the rudder and screwsB
completely around the vesselC
to leeward of the vesselD
to windward of the vessel
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单选题In order to keep the oil film on the cylinder liner during the running-in period, the piston rings are slightly rounded（）A
on both the external and internal top edgesB
on both the external top and bottom edgesC
on both the external and internal bottom edgesD
on all the four edges
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fuel oil pump will over-speed if dirt is not removedB
fuel oil transfer pumps cannot tolerate small amounts of dirt in the oilC
fuel injectors may be damaged by foreign particles in the fuel oilD
dirty fuel will clog the intake air filter
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单选题A turbocharged, four-stroke/cycle diesel engine has a larger valve overlap than a naturally aspirated four-stroke/cycle diesel engine, in order to in crease the （）.A
temperature of the exhaust gasesB
energy supplied to the turbochargerC
air pressure to the intake manifoldD
purge of exhausted gases from the cylinders
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单选题The intake ports of a two-strike/cycle diesel engine are opened and closed by the action of the （）A
camshaftB
piston movementC
exhaust valvesD
vertical drive
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