轮机英语关联题(轮机长大管轮)new

1、关 联 题 （173题）Passage 1Valve drive mechanismThe valve drive mechanism commands the inlet and exhaust valves at the required timing.The valve drive mechanism consists of an inlet and exhaust cam follower (8) each suspended in a plunger of the tappet assembly (7), two tubular push rods (4) with ball joi

2、nts, two nodular cast iron rocker arms (2) suspended in a rocker arm bearing bracket, two yokes (5) and a yoke guide pins. See Fig. 4-1.The tappet rollers follow the cam profiles and transfer the movements through push rods to the rocker arms. The rocker arms operate the inlet and exhaust valves thr

3、ough yokes (5).Lubrication for the rocker arms comes from the engines secondary oil supply manifold through drillings in the cylinder head and rocker arm bracket.The tappet assembly receives lubricating oil via channels in the engine block from the main supply manifold. For the roller and shaft, the

4、 oil is supplied through the guiding plunger. To compensate for heat expansion a clearance must exist between the rocker arm and yoke. All adjustments have to be done on a cold engine only.Fig-4-1 Valve drive mechanism1. According to the passage, the best time to adjust the valve clearance is _.A. b

5、efore the engine is started B. when the engine is runningC. after the engine has just been stopped D. when something has gone wrong with the engine2. The roller and the tappet assembly are lubricated by means of _. A. the main lube system B. the secondary oil system C. the special pumping system D.

6、the turbine oil system3. According to the passage, the valve drive mechanism does not include _. A. tappet rollers B. push rods C. nodular cast iron D. yokes and guide pins4. To close valves tightly, which clearance should be inspected according to the maintenance schedule? A. The one between the ca

7、m and the tappet roller. B. The one between the push rods and the ball joints. C. The one between the rocker aims and the yoke D. The one between two tubular push rods.AACCPassage 2Compressor cleaning during engine operation The compressor may be cleaned by water injection during the engine operatio

8、n. The cleaning process will have good results as long as the deposit formation has not gone too far. In ease a very thick hardened crest of dirt the compressor has to be dismantled for cleaning. In this method of cleaning the water is not acting as a solvent but instead removes the deposits mechani

9、cally by the impact of the water droplets. It is therefore recommended to use clean water without additives. The water should not contain any additives which might remain on the compressor blades. Periodically cleaning of the compressor (Fig. 4-2) prevents or delays excessive build-up of dirt but in

10、 no way replaces the usual overhauls where the turbocharger is completely dismantled. The turbocharger is provided with a water container (1). During the cleaning procedure the container is pressurized with the charge air (2) and from where the water is forced to the compressor inlet (3).1. Which of

11、 the following statements can be used to clean the compressor with the engine running? A. Water droplets Water with additives C. Charge air D. Hard crust2. What principal is used in this method of cleaning? A. The cleanser solves the deposits. B. The cleanser melts the deposits. C. The cleanser beat

12、s the deposits mechanically. D. The high pressure of the cleanser removes the deposits.3. Which of the following statements is not correct? A. The compressor needs regular cleaning. B. Periodical cleaning of the compressor contributes to reducing build-up of dirt. C. Its not necessary to dismantle t

13、he turbocharger if periodical cleaning of the compressor is performed. D. Additives should better be avoided during the cleaning process.4. The cleaning water should not contain any additives, because_. A. they may delay build-up of dirt B. they might remain on the blades of the compressor C. they m

14、ay be forced to the compressor inlet D. they are not good solventsACCBPassage 3Charge air cooler The engine is equipped with a charge air cooler. The insert type charge air cooler is mounted in a welded casing (air trunk) . The trunk is bolted to the engine block. Standard is a two-stage cooler moun

15、ted. The first stage, through which the charge air flows, is cooled with water from the HT cooling system and cools the charge air till approx. 90 -100. The second stage is supplied with water coming from the LT water system and cools the charge air further till the required temperature of approx. 5

16、0. By controlling the water flow through the LT cooler the charge air temperature can be kept constant at the required temperature. The circulating coolant water should always be under positive pressure and should be as clean as possible. The operating air temperature should be maintained by control

17、ling the coolant inlet temperature. Whilst the engine is running the air and coolant temperatures and pressures at inlet and outlet should be checked and logged periodically. Variations from normal indicate faults developing such as fouling of the film plates or obstruction of the water tubes. Check

18、 daily, during operation of the engine, the working of the telltale hole at the free end of the charge air receiver. The function of this hole is to inform the operator the presence of water in the charge air receiver. Under normal condition only compressed air should escape from this hole.1. Accord

19、ing to the passage, the expression “HT” probably means _. A. HIGH TANK B. HIGH TEMPERATURE C. HEAT TRANSMISSION D. HEAT TRANSFER2. In order to maintain the charge air temperature we should control _. A. the coolant inlet temperature coming from the first stage cooler B. the coolant flow coming from

20、the second stage cooler C. the coolant outlet temperature coming from the second stage cooler D. the coolant flow coming from the first stage cooler3. The charge air temperature departing from normal may indicate that _. A. condensate can be formed B. only compressed air should escape from the tellt

21、ale C. the film plates are becoming dirty or the water tubes are blocked by scale D. cooling water may have been carried into the cylinders4. The function of the telltale hole is to _. A. detect whether compressed air has escaped from the hole B. control the coolant inlet temperature C. determine wh

22、ether the coolant water is under positive pressure D. inform the operator the presence of water in the charge air receiverBBCDPassage 4 The vibration damper serves to reduce the torsional vibration generated by the crankshaft. The damper consists of a housing and a free rotating inertia ring support

23、ed by an axial bearing. It forms a totally enclosed unit. The free space between inertia ring and damper housing is filled with a high viscous fluid. When the crankshaft rotates at constant speed, the inertia ring will follow this movement. The combustion pressure exerted on each piston generates vi

24、bration in the crankshaft, and each variation generated by such a vibration will affect the movement of the inertia ring. The resulting shift of the ring to the damper housing is opposed by the viscous fluid and the vibration will be reduced. The energy, absorbed during the process, is converted int

25、o heat and then radiated to the surrounding air. Hence, proper ventilation of the damper is essential. The viscous damper fluid is during engine operation subjected to ageing and the fluid becomes more viscous. In sending fluid samples on a regular base to the damper manufacturer the rate in reducti

26、on of the viscosity can be determined. As sampling interval time is 6000 hours advised. Dampers with a too high fluid viscosity may cause crankshaft breakdown. The damper cover has two filling holes located 180o opposite each other and closed by screw-in filler plugs. If one of these plugs is access

27、ible, a fluid sample container can be screwed in and a sample taken with the damper in place. On a spare damper, sampling must be effected with the damper in the vertical position. For liquid sampling, a special kit can be ordered from Stork-Wartsila Diesel.1. The general description of the vibratio

28、n damper tells us that_. A. the free space between inertia ring and damper housing is filled with a low viscous fluid B. when the inertia ring moves at constant speed , the crankshaft follows this movement C. the damper is made up of a housing and a free rotating inertia ring D. no ventilation of th

29、e damper is necessary as the vibration reduction process absorbs little energy2. Which of the following statements is not true about maintenance of the viscous damper? A. Sampling interval time for determining the quality of the fluid is 6000 hours. B. For liquid sampling, a special kit can be used.

30、 C. On a spare damper, sampling must be effected with the damper in place. D. The viscous fluid in a damper becomes more viscous as time goes by.3. During the engine operation, the vibration damper can_. A. transfer the energy of the engine B. absorb the combustion heat C. oppose the crankshaft rota

31、ting D. reduce the vibration of the crankshaft4. According to the passage, we learn that two filling holes in the damper cover are used _. A. to recharge the fluid B. to ventilate the damper C. to fit the container D. to take the sampleCCDDPassage 5 The vibration damper employs a high viscous fluid

32、to oppose the shift of the inertia ring to thedamper housing. It is necessary to get samples to determine the rate in reduction of the viscosity. The steps to draw off the sample are as follows(Refer to the Fig. 4-3):1. Turn the engine until the drain plugs are easy accessible. Do not unscrew the dr

33、ain plug until the damper is luke warm (approx. 40oC ).2. Carefully tap the locking of the upper drain plug backwards, using a punch, and unscrew the threaded plug. Do not yet remove the plug!3. Unscrew one cap nut from the (plastic) liquid container.4. Remove the drain plug and screw the liquid con

34、tainer instead.5. Remove the outer cap nut from the liquid container. Make sure that no machine oil or dirt can enter the liquid container!6. Screw the outer cap nut again, once the liquid has reached the open end of the liquid container. The filling-up period of the liquid container may take from a

35、 few seconds up to more than an hour, depending on the liquid condition.7. Unscrew the liquid container from the damper and fit the drain plug using a new joint ring (supplied with the mounting kit).8. Fit the second cap on the liquid container. If no sample can be taken in this way, you can proceed

36、 as follows: - If still no liquid appears after a while, remove the second drain plug, too. - Supply nitrogen of 3.5 bar maximum pressure through the open filling hole. If no nitrogen is available, air may be used, provided this air is properly filtered and dry. - Once the liquid has reached the ope

37、n end of the liquid container, cut off the supply of nitrogen and screw the cap on the liquid container. - After the nitrogen supply has cut off, unscrew the liquid container, screw the second cap and fit both drain plugs. If a liquid sample cannot be obtained this way either, it can be assumed that

38、 the damper liquid has thickened to an inadmissible value, necessitating the replacement of the damper.1. According to the passage, we can learn that_. A. before using the container to draw off the sample, both ends of it are closed B. the liquid container must be washed with machine oil before samp

39、ling C. liquid sampling must take more than one hour D. two liquid samples should be taken every time2. If the liquid sample cannot be taken any way, it means_. A. nitrogen pressure is too low B. the quantity of the damper fluid is insufficient C. the viscous fluid in damper becomes too thick D. the

40、 method of liquid sampling is incorrect3. Which statement is tree about the sampling process? A. The drain plug can be unscrewed regardless of the damper temperature. B. The drain plug should not be removed until one cap nut from the liquid container is unscrewed. C. The outer cap nut must be screwe

41、d before the liquid reaches the open end of the liquid container. D. The drain plug can be fit by using the old joint ring.4. If no sample can be taken by removing the first drain plug, then which of the following is done? A. The second drain plug should be removed too. B. A pressure of 5.3 bar shou

42、ld be applied. C. Clean and damp air is used instead of nitrogen if the latter is not available. D. The nitrogen supply continues when the liquid has reached the outer end of the liquid container.ACBAPassage 6 At the first start, listen carefully for possible jarring sounds. If anything is suspected

43、, stop the engine immediately, otherwise stop the engine after 5 minutes idling. Check at least the temperatures of the main and big end bearings and of all other bearings which have been opened. Make visual inspection from below to the cylinder liners and piston skirts which have been opened. If ev

44、erything is in order, restart. Check that there is no leakage of gas, water, fuel or lubricating oil. Especially observe the fuellines, HP fuel pumps and injectors. Watch the quantities emerging from the leak oil pipes! Check that the starting air manifold is not hot at any cylinder (leaky starting

45、valve may cause explosion! After overhaul, the following instructions are important: - check pressure and temperature gauges. - check the automatic alarm and stop devices. - check the pressure drop over the fuel filter and lubricating oil filter. - check the oil level in the oil sump/oil tank. Estim

46、ate the condition of the oil. - check the de-aerating of the engine circulating water system. - check the quantity of fuel leak. - check the telltale holes for leaks. - check the circulating water quality - check the cylinder pressures. - listen for jarring sounds. - check the crankcase pressure. -

47、check the starting air manifold. Running-in is mainly intended to let piston tings wear to fit properly in the cylinder liner. Do not continuously run at constant load during the running -in process ( Fig. 4-4). It is important to vary the load several times. The ring grooves in the piston will have

48、 a different tilting angle at each load and consequently the piston ring has a different contact line to the cylinder liner wall.1. Paragraph 1 tells us that_. A. if we hear vibration sounds, we should stop the engine quickly, or allow it to operate at low speed for 5 minutes, then stop it and check

49、 everything B. if we hear vibration sounds, we should stop the engine quickly, otherwise the engine will be stopped automatically after 5 minutes C. if we hear explosion sounds we should stop the engine then check everything D. if we hear surging sounds, we should stop the engine immediately otherwi

50、se after 5 minutes the engine will be destroyed2. After overhaul, following instructions are important except_. A. release air from the engine circulating water system B. treat the circulating water if necessary C. make sure the pressure drop is enough besides the fuel filter D. make sure the quanti

51、ty of lube oil meets the requirement3. After piston overhaul, the running-in process should be carried out_. A. periodically at steady load B. occasionally at various load C. continually at constant load D. continually at various load4. When dealing with engine troubles, _. A. no leakage of lubricat

52、ing oil should be checked_. B. quantities of oil emerging from the leak oil pipes must be watched C. quality of the leak oil must be watched D. the number of the leaking fuel lines should be checkedACDBPassage 7 This sequence of events is made possible by substituting ports in the bottom of the cyli

53、nder wall for the inlet and exhaust valves. There are two groups of these ports, one for exhaust and the other for scavenging air, usually on the opposite sides of the cylinder, but in some designs both groups are arranged on the same side. The exhaust ports connect with the exhaust manifold, while

54、the scavenging ports communicate with the scavenging air receiver in which low-pressure air is stored. The exhaust ports are slightly higher than the scavenging ports, so that they are uncovered by the piston while the scavenging ports are still closed. (The following 2 questions are based on the pa

55、ssage above. )1. From the paragraph above, we know that_. A. In general, both exhaust ports and scavenging air ports are on the opposite sides of the cylinder B. The exhaust ports are on the opposite sides, but the scavenging air ports are on the same sides C. The scavenging air ports are on the opp

56、osite sides, but the exhaust ports are on the same sides D. Two groups of parts are never arranged on the same sides2. According to the above paragraph the exhaust ports link with_. A. the exhaust valves B. the scavenging air receivers C. the exhaust manifold D. the scavenging ports The engine is al

57、so provided with a governor which is designed to regulate the engine s speed by adjusting the quantity of oil injected. When the engine runs at a speed higher or lower than that is set, the governor will act automatically reduce or increase the fuel oil supply so that the engine can be adjusted. ( The following 2 questions are based on the pas