更多"Passages are drilled in the cranksh"的相关试题:
[单项选择]Although the crankshafts of medium diesel engines appear to be robust, they rely on the support of （） to develop their full strength.
A. the piston rods
B. the crank throws
C. the thrust bearings
D. the main bearings
[单项选择]The crankshafts of medium speed engines are almost invariably solid （） from a single piece of steel.
A. forged
B. cast
C. made
D. shrunk
[单项选择]The crankshafts on the large modern 2-stroke crosshead engines are （）big （）makes as a single unit and so are constructed by joining together individual forgings.
A. enough；to
B. too；to
C. such；so
D. so；that
[单项选择]Crankshafts of medium speed engines are （） from a single piece of steel.
A. unusually solid welded
B. never be solid forged
C. almost invariably solid forged
D. almost invariably be welded
[单项选择]Today, crankshafts for large 2-stroke crosshead engines are of the （）type.
A. semi-built
B. built-up
C. solid forged
D. individual forged
[单项选择]A drilled hole is accurately finished to size with a （）
A. center drill
B. finish drill
C. broach
D. reamer
[单项选择]The marine diesel engine is a type of diesel engine used on ships The （） of its operation is not very difficult to understand.
A. principle
B. principal
C. cause
D. case
[单项选择]The ports are drilled in the liners at an angle of approx 20℃ the result being that （） is given a rotary movement.
A. the scavenging air
B. the exhaust gases
C. the mixed air
D. the spray oil
[单项选择]Diesel oil may be used to cool （） of a diesel engine.
A. cylinders
B. exhaust valves
C. pistons
D. fuel valves
[单项选择]Mechanical lubricators for diesel engine cylinders are usually small reciprocating pumps which are （）.
A. operated manually once an hour
B. operated until the engine has started
C. placed into operation only at maximum load
D. adjustable to meet lubrication requirements
[单项选择]Diesel engine mufflers accomplish noise reduction by （）
A. reducing exhaust gas velocity
B. increasing the frequency of gas vibration
C. the use of long head pipes
D. the use of zinc electrodes
[单项选择]Diesel fuel vapors （）.
A. can not be ignited by a spark unless the vapor is in a confined space
B. are nontoxic in all concentrations
C. can not be ignited by a spark unless they are at their auto-ignition temperature
D. are heavier than air
[单项选择]Diesel engine crankshaft deflection readings are generally taken at four crank positionsGood engineering practice requires the deflection gage or indicator to be（）
A. placed as near the crankpin axis as possible
B. removed each time the crankshaft is repositioned
C. left in place for all four readings
D. reset to zero for all four readings
[单项选择]An operating turbocharged diesel engine that suddenly loses power, is due to a/an（）
A. restricted turbocharger air intake
B. oil leak into the turbocharger
C. dribbling injector
D. low fuel viscosity
[单项选择]Constant cooling the various components of diesel engine has a number of functions except for （）.
A. good lubrication
B. low thermal stress
C. good mechanical properties
D. acid corrosion
[单项选择]High diesel engine cooling water temperatures can be caused by （）.
A. a worn water pump
B. not enough coolant
C. air in the cooling system
D. all of the above
[单项选择]Lubricating oil systems for diesel engine journal bearings are usually lubricated by which of the following types of lubricating oil systems?（）
A. Splash
B. Gravity
C. Pressure
D. Bypass
[单项选择]Diesel engine electric starting motors generally require heavier duty motors and motors and operate at higher voltages than comparable starting motors for gasoline engines due to（）
A. higher speed required
B. flywheel-effect
C. lower starting temperatures
D. higher compression pressures
