单选题The injector pump is operated by a cam which drives the （） up and down.ApistonBdrumCplungerDbarrel
单选题
The injector pump is operated by a cam which drives the （） up and down.
A
piston
B
drum
C
plunger
D
barrel
参考解析
解析：
暂无解析
相关考题：
Which of the following is operated from the main engine room console on an automated vessel?A.Fire pump and lube oil pumpB.Lube oil pump and distilling plantC.Distilling plant and shaft alley doorD.Shaft alley door and fixed CO2 release
第一组Older loop scavenged engines may have a single injector mounted centrally in the cylinder head. Because the exhaust valve is in the center of the cylinder head on modern uniflow scavenged engines the fuel valves (2 or 3) are arranged around the periphery of the head. The pressure at which the injector operates can be adjusted by adjusting the loading on the spring. The pressures at which the injectors operate vary depending on the engine, but can be as high as 540 bar. Some injectors have internal cooling passages in them extending into the nozzle through which cooling water is circulated. This is to prevent overheating and burning of the nozzle tip. Injectors on modern engines do not have internal cooling passages. They are cooled by a combination of the intensive bore cooling in the cylinder head being close to the valve pockets and by the fuel which is re-circulated through the injector when the follower is on the base of the cam or when the engine is stopped. As well as cooling the injector, re-circulating the fuel when the engine is stopped keeps the fuel at the correct viscosity for injection by preventing it from cooling down. Fuel injectors must be kept in good condition to maintain optimum efficiency, and to prevent conditions arising which could lead to damage within the cylinder. Injectors should be changed in line with manufacturers recommendations, overhauled and tested. Springs can weaken with repeated operation leading to the injector opening at a lower pressure than designed. The needle valve and seat can wear which together with worn nozzle holes will lead to incorrect atomization and dribbling.Modern uniflow scavenged engines have______.A.a single injector mounted in the center of the cylinder headB.several injectors mounted around the external boundary of the cylinder headC.a single injector mounted at the external boundary of the cylinder headD.several injectors mounted in the center of the cylinder head
Which statement is NOT true?A.In a simple vane pump, the rotor and cam ring are exactly concentricB.Balanced vane pump has an elliptical cam ringC.Liquid in both gear pump and vane pump are forced out to the outlet.D.Balanced vane pumps can work at a higher pressure than the simple vane pump
An increase in the fuel injection pump discharge pressure can be caused by a/an _______.A.leaking delivery valveB.excessive bearing end playC.plugged injector spray holeD.increased plunger stroke
A spur gear pump should be operated with the discharge valves ______.A.slightly openedB.throttledC.fully openedD.halfway opened
单选题The injector pump is operated by a cam which drives （） up and down.Athe needle valveBthe plungerCthe pistonDthe cylinder
单选题The injector pump is operated by a cam which drives the plunger （）.Atop and bottomBto and froCup and downDback and forth
单选题The plunger in the fuel injector pump, usually operated by a （）, is driven up and down when working.AcrankshaftBcamshaftCpiston rodDrack and pinion
单选题The hot expanding gas rotates the blades of the exhaust turbine, thus giving out large part of its power, which drives （）.Athe oil separatorBthe fresh water generatorCthe compressorDfire pump
单选题On a ship，a fire pump may be used for other purposes if（）.Athe other services are run off a reducing station with a pressure gageBa separate fire pump is available for use on the fire mainCall other services are operated by a manifold near the pumpDAll of the above
单选题If a centrifugal bilge pump were continually operated with the discharge valve closed the （）.Amotor overload would openBrelief valve would openCpump would eventually overheatDmotor would overheat
单选题Blow-off of the relief valves of the main cylinders during operation indicates （）.Athe cylinder cover is crackedBthe injector holes is cloggedCthe cams are not properly setDfuel pump is leaking
单选题Hydraulically, servo-operated, automatic, change over valves, utilized in a two ram hydraulic steering gear, serve to（）Aallow an alternate main pump to start in the fully loaded condition thus developing immediate full torqueBprevent either main pump from being hydraulically motored when idle by cross pressure flowCprevent both units from operating simultaneously which could result in doubling the flow of oil and pressure leading to over pressurization of the systemDall of the above
单选题Which of the following is operated from the main engine room console on an automated vessel?（）AFire pump and lube oil pumpBLube oil pump and distilling plantCDistilling plant and shaft alley doorDShaft alley door and fixed CO2 release
单选题The fuel injector pump is operated by （） which drives the plunger up and down.Aa separate motorBa camCa generatorDa chain
单选题The compressed air is admitted to each cylinder through a cam operated by starting air valve when the piston has just passed its （）.ABDCBTDCCBBDCDATDC
单选题Which of the listed items should be secured before performing any maintenance on a solenoid operated air start valve?（）AElectric power and starting airBLube oil standby pump and control airCHydraulic switch and engage jacking gearDMotor drain and pneumatic control system power
单选题Most fuel injection nozzles are opened by （）.Afuel oil pressureBa cam operated followerCa spring-loaded pressure plateDtiming gears keyed to the crankshaft
单选题The amount of fuel injection into a diesel engine cylinder by a unit injector, is controlled by（）Athe firing pressure in the cylinderBa metering helix inside the pumpCvarying the physical length of the plunger strokeDvarying the clearance between the injector cam and the injector rocker arm
单选题The injector pump is operated by a cam which drives the （） up and down.ApistonBdrumCplungerDbarrel
单选题Injectors on modern engines are cooled by a combination of the intensive bore cooling in the cylinder by a combination of the intensive bore pockets and by the fuel which is re-circulated through the injector when the follower is on the （）of the cam or when the engine is stopped.AslopeBbaseCtopDbottom
单选题One remedy for a high firing pressure, in addition to a high exhaust temperature in one cylinder of a diesel engine, is to （）Aincrease scavenge air pressureBreduce fuel booster pump pressureCadjust the fuel rackDretard fuel injector timing
单选题An increase in the fuel injection pump discharge pressure can be caused by a/an （）Aleaking delivery valveBexcessive bearing end playCplugged injector spray holeDincreased plunger stroke
单选题There is an injection pump for each cylinder, which is usually operated once every cycle by （） on the camshaft.Aa gearBa camCa rodDa miler
单选题When the follower is on the base circle of the cam, the pump plunger is at the （） of its stroke.AtopBmiddleCbottomDany of the above
单选题A spur gear pump should be operated with the discharge valves （）.Aslightly openedBthrottledCfully openedDhalfway opened
单选题Which portable fire extinguisher is normally recharged in a shore facility?（）ADry chemical (cartridge-operated)BWater (cartridge-operated)CWater (pump tank)DCarbon dioxide