更多"An advantage of aluminum pistons, w"的相关试题:
[单项选择]Aluminum pistons have （） coefficient of thermal expansion compared with those of cast iron.
A. higher
B. lower
C. the same
D. none of the above
[单项选择]A major advantage of the NAVTEX system when compared to other systems is that（）.
A. the information can be received on an ordinary FM radio
B. warnings are printed out for reading when convenient
C. broadcasts are at scheduled times
D. a low frequency band is used for long distance transmission
[单项选择]The advantage of a centrifugal pump as compared with a reciprocating pump is that （）.
A. discharge is continuous
B. it has no internal valves
C. upon accidental closing of discharge valve, excessive pressure will not build up
D. all of the above are true
[单项选择]One advantage of a flash distilling plant when compared to a submerged tube distiller is（）
A. greater distillate purity through high temperature evaporation
B. cold shocking for scale removal is not required
C. less internal corrosion because of lower brine density
D. less feed-water is required for equal plant capacity
[单项选择]A supercharged diesel engine when compared to a similar naturally aspirated diesel engine, will develop an increase in （）
A. ignition lag
B. engine horsepower
C. lube oil system pressure
D. specific fuel consumption
[单项选择]When compared to air temperature,which factor is most useful in predicting fog?（）
A. Vapor pressure
B. Dew point
C. Barometric pressure
D. Absolute humidity
[单项选择]What’s the advantage when using the satellites?（）
A. The message can be directed to the desired location
B. The message can follow the earth‟s curvature
C. The quality of message can not be affected by climatic
D. the range of the message extend and the quality of reception is improved
[单项选择]Pistons of marine medium speed diesel engines may be made of （） in order to keep the weight down for balancing purpose at high speed.
A. lead
B. forged steel
C. alloy steel
D. aluminum alloy
[单项选择]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. slow
B. quick
C. arranged
D. high
[单项选择]Cast iron pistons used in large propulsion diesel engines are constructed with （）
A. not taper what so ever
B. the skirt being tapered and smaller than the crown
C. the skirt being tapered and larger than the crown
D. the crown being tapered and smaller than the skirt
[单项选择]Trunk type diesel engine pistons are effectively cooled when heat is（）
A. radiated through the engine block
B. transferred to water cooled cylinder walls
C. conducted through the piston crown
D. transferred to escaping exhaust gases
[单项选择]（）, we kept removing the pistons.
A. Late as it was
B. As it was late
C. Since it was late
D. Because of its late
[单项选择]（） provide the water to the pistons.
A. Pneumatic pipes
B. Hydraulic pipes
C. Telescopic pipes
D. Operating gas pipes
[单项选择]Many cast iron pistons are designed with heat dams, which serve to （）
A. keep piston crown temperatures elevated for smoother combustion
B. reduce the possibility of overheating the top compression ring
C. help retain the heat of compression to prevent ignition delay
D. help retain the heat of compression to prevent combustion knock
[单项选择]Trunk-type diesel engine pistons are most effectively cooled by heat（）
A. conducted through the engine block
B. conducted to water cooled cylinder walls
C. conducted through the piston crown
D. loss to escaping exhaust gases
[单项选择]The pistons are cooled by oil supplied from the forced （） system.
A. fresh water
B. sea water
C. lubrication
D. fuel oil
[单项选择]（） pistons have low inertia and high coefficient of thermal expansion.
A. Cast iron
B. Cast steel
C. Forged steel
D. Aluminum
