网友您好, 请在下方输入框内输入要搜索的题目:

题目内容 (请给出正确答案)
单选题
An important consideration in selecting a lubricating oil for use in a refrigeration compressor is for the oil to ()
A

have a high viscosity index

B

mix readily with refrigerant

C

have a high freezing point

D

have a low pour point


参考答案

参考解析
解析: 暂无解析
更多 “单选题An important consideration in selecting a lubricating oil for use in a refrigeration compressor is for the oil to ()A have a high viscosity indexB mix readily with refrigerantC have a high freezing pointD have a low pour point” 相关考题
考题 In an auxiliary diesel engine bypass type lubricating oil system, the main lube oil pump forces_______ .A.all of the oil used by the engine through a filterB.some of the oil used by the engine through a filterC.some of the oil used by the engine through a centrifugeD.all of the oil used by the engine through a centrifuge

考题 单选题The remaining oil in the lubricating pipes and ducts should be blown out with ().A atmosphereB the fresh waterC compressed airD chemical compounds

考题 单选题The primary purpose of oil control rings on a diesel piston is to()A provide a reservoir for cylinder lubricationB pump oil into the combustion space for cylinder coolingC prevent excessive lubricating oil consumptionD allow hydraulic oil film formation on the cylinder

考题 单选题One characteristic of a lubricating oil adversely affecting the result of centrifuging is ()A high TBN valueB low oil floc pointC low oil demulsibilityD low oil neutralization number

考题 单选题Excessive lubricating oil consumption in a running diesel engine can be caused by ()A clogged lube oil pipingB excessive valve-guide clearanceC high lube oil viscosityD low lube oil temperature

考题 单选题The amount of lubricating oil in the drain tank should be checked by ().A measuringB sounding rodC meteringD weighting

考题 单选题Which of the following will be the function of lubricating oil used in marine engines?()A to remove heat from oil cooled pistonsB to wash away wear detritusC to neutralize acidic productsD all of the above

考题 单选题When fuel oil has seriously contaminated a diesel engine lubricating oil, you should ().A filter to remove the fuel oilB use the settler to remove the fuel oilC remove the fuel oil by centrifugingD drain and then renew the lube oil supply

考题 单选题Two main lubricating oil pumps are usual and are obligatory in ().A container shipsB bulk carriersC passenger shipsD barges

考题 单选题What is one effect of running a diesel engine at too cool a temperature? ()A Buildup of sludge in the lubricating systemB Excessive fuel consumptionC Severe heat stresses on mechanical partsD Foaming of the lubricating oil

考题 单选题The ignition quality of a fuel oil is an important operational consideration because it()A indicates the amount of abrasive material in the fuelB affects the starting ability of a cold engineC determines the amount of fuel penetration engineD affects the compression ratio of an operating engine

考题 单选题On engines having oil cooled pistons the lubricating oil pre-heater must be put into operation and the rate of heating so () that the temperature of the piston cooling oil returns are 32℃ to 35℃ over a period of at least two hours.A slowB quickC arrangedD high

考题 单选题The ()should be kept running for about half an hour after FWE.A crankcase lubricating oil pumpB fuel oil pumpC air compressorD auxiliary blower

考题 单选题Engine coolant accumulating in the diesel engine lubricating oil can result from a ()A low oil pressureB high coolant pressureC leaking fuel injectorD cracked cylinder head or liner

考题 单选题In a normally operating diesel engine, the main cause of lubricating oil contamination in the crankcase is a result of the ().A metal particles loosened by wearB air when no air cleaners are usedC condensation of water vaporsD breakdown of the lubricating oil by dilution

考题 单选题() providing lubricating films, oil used in marine diesel engines have to remove heat from oil cooled piston.A Except forB BesideC ExceptD In addition to

考题 单选题If the analysis of used lube oil indicates a high content of iron particles, this could indicate()A corrosive deterioration of a bearingB inadequate air filtrationC excessive ring and liner wearD excessive cooling of lubricating oil

考题 单选题The function of lubricating oil is to ()A maintain even distribution of bearing wearB maintain a constant oil temperatureC maintain a pressurized film between moving surfacesD remove entrained water

考题 单选题Lubricating oil viscosity in an operating diesel engine can be reduced by()A increasing cooling water flowB increasing lube oil flowC dilution by fuel oilD adding SAE 70 oil

考题 单选题The function of lubricating oil is to ().A reduce friction between moving surfacesB provide even distribution of bearing wearC reduce the accumulation of harmful detergentsD maintain a constant oil temperature output at each beating

考题 单选题Lubricating oil systems for diesel engine journal bearings are usually lubricated by which of the following types of lubricating oil systems?()A SplashB GravityC PressureD Bypass

考题 单选题The ()pump is usually used as the lubricating oil pump.A turbineB screwC vaneejectorD centrifugal