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Lubricating oil systems are fitted with a wide variety of strainers some of which can be cleaned in site while others have replaceable cartridgesThe bold and italic word “which” means ().
A . lubricating oil
B . lubricating oil systems
C . strainers
D . cartridge
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Fuel oil tanks must be fitted with () that can be closed rapidly and remotely in the event of an emergency such as a fire.
A . stop valves
B . non-return valves
C . quick closing valves
D . relief valve
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The degree to which the viscosity of an oil will change with a change in temperature is indicated by the ().
A . weight designation
B . viscosity index
C . pour point
D . thermal change value
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Foaming of the oil in a refrigeration compressor crankcase is caused by ().
A . refrigerant boiling out of solution from the lube oil
B . liquid refrigerant flooding the compressor and system
C . lube oil viscosity being reduced by refrigerant dilution
D . compressor suction pressure suddenly increasing
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Some refrigeration systems have chemical moisture indicators installed in conjunction with the sight glass in the liquid lineIf excess moisture is present in the system, the indicator will ()
A . activate the driers
B . change color
C . secure the compressor
D . add a predetermined amount of liquid drier
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Excessive oil foaming in the crankcase of a refrigeration compressor can result in ().
A . overheated compressor bearings
B . excess lube oil viscosity
C . carbon deposits on the compressor piston rings
D . wax crystals forming in the lubricant
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In a refrigeration system, foaming of the crankcase oil may cause the ().
A . expansion valve to overfeed
B . compressor to knock
C . water regulating valve to fail
D . crankcase drains to plug
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Insufficient refrigerant in a refrigeration plant may result in ().
A . high discharge pressure
B . frosting of the crankcase
C . high temperature of the overboard water
D . low suction pressure of compressor
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In an engine with a pot-shaped piston, some lubricating oil from the main bearing will pass along a drilled passage in the crankshaft to the bottom end bearing and then up a connection rod to the ().
A . crosshead
B . crankpin
C . crank journal
D . gudgeon pi
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With respect to the flow of lubricating oil through a diesel engine, the lube oil coolers are located after filters in order to ().
A . allow filtration of less viscous oil
B . decrease the pressure drop across the filter
C . improve overall filtration
D . all of the above
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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
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A liquid sight flow indicator in a refrigeration system is examined and gas bubbles are noted in motion with the fluid flowThis means ().
A . the system is fully charged
B . there is air leaking in from the condenser
C . ice crystals are forming in the refrigerant
D . the system contains less than a full charge of refrigerant
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In engines with system, the lubricating oil can be added to the engine through the filling hole in the crankcase cover, by using a hand oil can, or through the separator pipe()
A . lubricating oil
B . dry sump
C . circulated tank
D . wet sum
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In general, the oil mist defectors include a base plate with air blast pumpThe function of air blast pump is to ()crankcase.
A . supply clean air to the measuring compartment of the units for more accuracy
B . generaate the pressure required for the extraction of the oil mist from the
C . generate the pressure required for the extraction of the oil mist from the crankcase
D . supply clean air to the measuring track of the units for more accuracy
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Before dismantling the pipe, would you ()the oil retained in the hose with ()?
A . flash;fresh air
B . wash;fresh water
C . flush;compressed air
D . rush;diesel oil
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When two oil separators are working in series, they should work with ()
A . both as clarifiers
B . first one as clarifiers, second one as purifier
C . both as purifiers
D . first one as purifier, second one as clarifier
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The consistent burning of fuel oil with a high sulfur content in a diesel engine will result in ()
A . clogged fuel injection pumps
B . increased cylinder liner wear
C . intake valve stem corrosion
D . varnish deposit on pisto
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Excessive oil foaming in the crankcase of a refrigeration compressor at start up can cause().
A . compressor damage from improper lubrication
B . refrigerant absorption by the lubricant
C . increased viscosity in the lubricant
D . carbon deposit on the compressor suction valve
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In an engine with a pot-shaped piston, some lubricating oil from the main bearing will pass along a () in the crankshaft to the bottom end bearing andthen up a connection rod to the gudgeon pin.
A . telescopic pipes
B . large bore
C . drilled passage
D . tied rod
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If liquid refrigerant accidentally comes in contact with the eyes, () immediately.
A . rub the eyes
B . irritate the eyes
C . wash the eyes with a heavy boric acid solution
D . obtain medical hel
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A cargo of refrigerated fruit is packed in crates with transverse members dividing the crate in two equal parts. Which statement is TRUE?()
A . The cargo block should be tightly packed if the cargo is suitably chilled upon delivery to the vessel
B . Both sides of each crate must be checked for the temperature and the appearance of the fruit
C . The cargo block should be stowed with air channels built throughout the stowed cargo
D . The crates should NEVER be stowed brick fashio
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You are in a tropical port.The refrigeration machinery on a container loaded with air-cooled fruit fails.It cannot be repaired for 18 to 24 hours.Which step should you take to reduce the temperature rise and spoilage of the fruit ________.
A.Discharge a cylinder of nitrogen into the container
B.Shade the container and periodically hose it down
C.Seal any ventilation openings and add dry ice
D.Spread ice over the top layer and in any voids within the container
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Excessive circulation of the lubricating oil with the refrigerant in a refrigeration system will cause______.
A.carbon deposits on the compressor suction valves
B.the evaporator temperature to increase
C.rapid corrosion of the thermal expansion valve
D.no operating problems
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根据所听到的内容作答_____。 A)The door will open with just a touch of the finger。 B) The refrigerator can figure out how much milk to buy. C) The robot can do all the housework very efficiently. D)The house Call put out a fire in a very short time.