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A large, low-speed, crosshead, main propulsion diesel engine using residual fuel oils must have a cylinder oil having a ()
A、the use of a poor quality oil
B、the deterioration of its properties
C、the formation of deposits
D、the reduction in heat transfer ability
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The main function of tie rods in the construction of large, low speed diesel engines is to().
A . stiffen the bedplate in way of the main bearings to increase the engines longitudinal strength
B . accept most of the tensile loading that results from the firing forces developed during operation
C . mount the engine frame securely to the hull to prevent shaft coupling misalignment
D . connect the crosshead solidly to the piston rod
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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 gase
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Today, crankshafts for large 2-stroke crosshead engines are of the ()type.
A . semi-built
B . built-up
C . solid forged
D . individual forged
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Smaller engines can be made more rigid than large ones and may not have ().
A . through bolts
B . turbo-chargers
C . bed plates
D . colum
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One method of constructing large marine diesel engines and reducing the total engine frame weight is through ().
A . casting interlocking components
B . welding plates to form sections for assembly
C . forging integral components
D . case hardening integral component
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Large marine diesel engines of crosshead construction generally have two systems of lubrication: a total loss system feeding the () and a recirculation system lubricating the running gear and cooling the piston.
A . cylinder liners and piston rings
B . main bearings
C . crankpin bearings
D . turboblower
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Which of the following procedures should be carried out to permit the use of a crosshead engine with an inoperable after-cooler?()
A . Bypass the after-cooler to operate at speed
B . Run at reduced speed until the cooler can be repaired or renewed
C . Switch to diesel fuel and run at full speed
D . Nothing need to be done due to the low heating value of heavy fuel
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In diesel engines designed with a crosshead, the motion of the piston rod can be described as ().
A . reciprocating at the piston pin, rotary at the crank pin
B . reciprocating at the crank pin, rotary at the piston pin
C . straight reciprocation
D . straight rotatio
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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
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A large, low-speed, main propulsion diesel engine uses sea water to directly cool the ().
A . cylinder heads
B . exhaust valves
C . scavenging air
D . injector
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() can be found on most medium to large merchant vessels even if the main engine is either a steam turbine or 2-stroke crosshead engine.
A . The medium speed 4-stroke trunk piston engine
B . The low speed 2-stroke crosshead engine
C . The medium speed 2-stroke crosshead engine
D . The low speed 4-stroke trunk piston engine
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Large crosshead type engine generally has two lubrication systems, a function performed only by crankcase oil system is()
A . lubricating
B . cooling
C . cleaning
D . neutralizing
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The diesel engine is a type of ().
A、A. turbine engine
B、B. gas turbine
C、C. steam engine
D、D. internal combustion engine
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Mist detectors used on large low-speed main propulsion diesel engines monitor and check for the presence of ().
A . fuel oil vapor at the sludge tank vent
B . unburned fuel vapors in the scavenge air receiver
C . lube oil vapors in the crank case
D . lube oil vapors in the engine room
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Exhaust valve openings in a diesel engine cylinder head are made as large as practical to ()
A . increase back pressure during the exhaust process
B . facilitate periodic replacement of the valves
C . reduce the pumping loss associated with scavenging
D . reduce tension on valve spring
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In some modern large diesel engines, which of the following is used as the support for the main bearings?()
A . Bedplate
B . Block
C . Base
D . Sum
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On a large diesel engine installation, crankshaft axial alignment is maintained by the ()
A . piston rod guides
B . engine thrust bearing
C . crosshead bearing
D . main shaft flexible coupling
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Which of the listed types of starting systems is often used on large, low-speed, direct reversing, main propulsion diesel engines?()
A . Electric
B . Hydraulic
C . Air
D . All of the above
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Most large, low-speed, main propulsion diesel engines use duplex lube oil strainer to ()
A . decrease the time required between cleanings
B . removes all large and small foreign objects
C . ensure a positive flow of oil at all times
D . ensure that all lube oil has been treated twice
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Thermocouple pyrometers are used on large, main propulsion diesel engines to indicate the temperature of the()
A . cooling water leaving each cylinder
B . fuel oil entering the injector
C . exhaust gases at various locations
D . lube oil at the bearing supplie
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There are three types of large arteries, elastic arteries and small arteries.