轮机英语三管轮试题 分油机

Lesson 17

1682. Emulsification of oil will occur when mixed with

A. air

B. black oil

C. water

D. ice cream

1683. A centrifuge arranged to separate two liquids is known as_____.

A. an oily water separator

B. a purifier

C. a centrifugal compressor

D. a clarifier

1684. A centrifuge arranged to separate impurities and small amounts of water from oil is known as_____.

A. an oily water separator

B. a purifier

C. a centrifugal compressor

D. a clarifier

1685. When a clarifier is running the impurities and water collect at the bowl_____.

A. center

B. periphery

C. inlet

D. upper parts

1686. For many years marine centrifuges were designed for_____ operation, that is the machines were run for a period during which solids accumulated in the bowl. The machine was stopped when the accumulated solids began to impair its performance.

A. purifying

B. batch

C. long period

D. temporary

1687. For a purifier, changing to a gravity disc with larger hole diameter will move the interface towards the_____.

A. bowl periphery

B. bowl center

C. upper surface

D. lower surface 1688. For a purifier changing to a gravity disc with smaller hole diameter will move the interface towards the_____.

A. bowl periphery

B. bowl center

C. upper surface

D. lower surface 1689. The_____ of the gravity disc is too big. It cause oil to flow through the water outlet. We changed the disc and no oil is found in the water outlet.

A. gravity

B. diameter

C. circumference

D. cylinder

1690. Dirty oil must be_____ before being used again .

A. mixed with clean oil

B. purified

C. heated

D. strained

1691. Which of the following influences the position of the interface between the liquid seal and the oil in a purifier?

A. Height of the machine

B. Temperature of the liquid seal

C. Gravity disc

D. Bowl diameter

1692. For a L.O. purifier, if the back pressure of the oil outlet is too high, the interface between oil and water in the bowl will_____.

A. be interrupted

B. move downwards

C. move outwards

D. retain original position

1693. When in operation, it is unavoidable that a small amount of oil_____ through

leakage, and in order to compensate for these leaks the system is connected to a feed pump.

A. escapes

B. overheats

C. expands

D. accelerates

1694. Coalescence is the breakdown of surface tension between oil droplets in an oil/water mixture, which causes them to join and_____ in size.

A. expand

B. extract

C. increase

D. decrease

1695. When a centrifuge is arranged to separate impurities and small amount of water from oil, it is known as a_____.

A. purifier

B. separator

C. filter

D. clarifier

1696. _____ is arranged for cleaning the lubricating oil in the system and clean oil can be provided from a storage tank.

A. A filter

B. A centrifuge

C. A distiller

D. A generator

1697. In a purifier, the interface between the liquid seal and the oil should be positioned as close as possible to_____.

A. the outlet of oil

B. the outlet of water

C. the bowl periphery

D. the center of bowl

1698. ____ is the breakdown of surface tension between oil droplets in an oil water mixture which causes them to join and increase in size.

A. Wear

B. Contaminating

C. Coalescence

D. Coarse separating

1699. The position of the interface between oil and water within the centrifuge is achieved by the use of_____.

A. gravity disc

B. centrifugal bowl

C. a stack of discs

D. main sealing ring 1700. To start the ejection process the oil feed to the centrifuge is first shut off and the oil remaining in the bowl removed by admitting_____.

A. flashing water

B. operating oil

C. flushing water

D. sealing water 1701. The interface between the liquid seal (water) and the oil should be positioned_____ possible to the bowl periphery.

A. as far as

B. as soon as

C. as close as

D. as closer as

1702. What is used to purify water and foreign matters from the fuel oil in the following?

A. Compressor

B. Separator

C. Evaporator

D. Fuel pump

1703. They understand the_____ of automatic sludge discharging of the purifier. But they are not good in practice.

A. principle

B. principal

C. theory

D. case

1704. The diameter of the gravity disc is too big. It causes oil to flow through the water outlet. We changed the disc and no_____ is found in the water outlet.

A. water

B. oil

C. scale

D. ridge

1705. If oil density were greater than water' s, the oil separator_____.

A. did work

B. would work well

C. didn't work

D. wouldn't work

1706. Sediment collects in a tubular purifier_____.

A. on top cover

B. on sides of bowl

C. in drain line on the discs

D. on the discs

1707.. Both fuel oils and lubricating oils require _____________before passing to the engine.

A. treatment

B. heating

C. cooling

D. boiling 1708. The treatment of the fuel oils involves storage, heating, filtering and ____________.

A. centrifuging

B. pressurizing

C. atomization

D. igniting 1709. ____________is used to separate two liquids or a liquid and solids as in contaminated oil.

A. Oily-water separator

B. Purifier

C. Clarifier

D. Centrifuge

1710. Where a centrifuge is arranged to separate two liquids, it is known as a ___________.

A. purifier

B. clarifier

C. liquid-separator

D. oily-water separator

1711. Where a centrifuge is arranged to separate impurities and small amounts of water from oil it is known as a ____________.

A. A. Oily-water separator

B. Purifier

C. Clarifier

D. Centrifuge

1712. “A centrifuge consists of an electric motor driving a vertical shaft on the top of which is mounted the bowl assembly.”According to this sentence, we can know that ____________is mounted on the top of the vertical shaft.

A. a centrifuge

B. an electric motor

C. a bowl assembly

D. a driving motor

1713. A centrifuge of which the bowl is arranged as the upper and lower parts separate discharges the sludge ____________.

A. by opening the separator manually

B. by separating the lower part from the upper part automatically

C. by separating the upper part from the lower part automatically

D. continuously

1714. Before the in a purifier is ejected, ______________.

A. the oil feeding is stopped and replaced by admitting flushing water.

B. the flushing water feeding is stopped and replaced by admitting oil.

C. the feeding of dirty oil and flushing water is stopped.

D. the feeding of dirty oil and flushing water is admitted.

1715. Main engines as well as auxiliary engines operating on heave fuel should have continuous ______ on the lubricating oil, either according to the bypass or batch principles.

A. filtering

B. centrifuging

C. depositing

D. operating

1716. Modern centrifuge designs enable continuous over a considerable period of time. This is achieved by _____ which is timed to discharge the sludge at regular intervals.

A. an injection process

B. an ejection process

C. a separation process

D. a heating process

1717. When two oil separators are working in series, they should work with ___ A. both as clarifiers B. first one as clarifier, second one as purifier

C. both as purifiers

D. first one as purifier, second one as clarifier

1718. One of the reasons that cause oil flowed from sludge outlet of a self –cleaning separator is ___.

A. seal water supply be cut off

B. make up water supply be cut off

C. oil outlet valve closed or not open sufficiently

D. the flow rate of oily water is too much

1719. When separating lube oil in oil separator, the optimal separating quantity is

__of the rated quantity on name plate

A. 100%

B. 1/2

C. 1/5

D. 1/3

1720. When separating fuel oil in oil separator, the separating quantity is ___of the rated quantity

A. 100%

B. 80%

C. 1/2

D. 1/3

1721. The separating effect of oil separator is not good, the reason may be __

A. too little seal water

B. improper gravity disc

C. oil discharging pump not working very well

D. low water level of the working water

1722. When separating the lube oil without additive, it is usually cleaned with hot water .the aim is to remove __from it

A. acid

B. sludge

C. mechanical impurity

D. salinity

1723. When finish working on the oil separator, you should ___firstly

A. cut off the power

B. cut off the oil inlet

C. open guide water valve

D. close oil outlet valve

1724. To ensure oil separator working in normal condition, the interval between two sludge dischargings should not exceed ____

A. 2h

B. 4h

C. 5h

D. 6h

1725. _______can cause oil flow from water outlet of a separator

A. oil inlet valve opening too quickly

B. oil temperature too high

C. diameter of gravity disc too small

D. viscosity of oil too low

1726. ____ can not cause oil flow from water outlet of self cleaning separator

A. oil temperature too high

B. diameter of gravity disc too large

C. oil temperature too low

D. high level tank out of water

1727. ____can cause oil flow from sludge outlet of self cleaning separator

A. too much sludge accumulated in separator bowl

B. diameter of gravity disc too large

C. high level tank lack of water

D. oil input too rapidly 1728. ________ are required to remove small quantities of water from a much larger amount of oil. Additionally it must separate solids.

A. Incinerators

B. Centrifuges

C. Oily water separators

D. Incinerator

1729. On board supply vessels, a centrifuge is normally used to purify ___________.

A. cooling water

B. fuel oil

C. sea water

D. diesel intake air

1730. For optimum results, centrifugal purification of heavy fuel oil should be accomplished with the fuel at the lowest practicable _________.

A. throughput

B. additive percent

C. cetane number

D. TBN number 1731. Heavy residual fuel oils are heated prior to centrifuging to __________.

A. reduce fuel weight

B.increase specific gravity

C.separate fuel from lube oil

D.reduce fuel viscosity

1732. In a disk-type lubricating oil purifier, ___________________.

A. the purifier driving gears are lubricated by the reclaimed.

B. oil as it leaves the bowl all dirt and sludge are automatically discharged with the cooling water.

C. sealing water must never be supplied until after oil is fed to the unit.

D. deterioration of the bowl ring gasket will cause the purifier to lose its water seal. 1733. The size of the discharge ring used for the efficient operation of a disk type purifier is dependent upon the ______.

A. rated capacity of that purifier

B. viscosity of the oil being purified

C. maximum design speed of that purifier

D. specific gravity of the oil being purified

1734. One engine manufacturer recommends heavy fuel oil should not be heated above 80o C to 95o C (176o F to 203o F) before purification. This upper limit should be

observed to ensure against _______________.

A. flattening of the bowl neoprene O-rings

B. operation within the explosive range of the fuel

C. excessive purifier operating pressures

D. excessive oil viscosity

第47期轮机英语

47期轮机英语考试题目 一单项选择题 A1.The___ engine is used for alternators and some times for main propulsion provide a propeller of between 90 to 120 rpm. A.four-stroke B.two-stroke. C.slow speed D.reversible B2.The abbreviation”MIP”stands for____, A.middle indicating pressure B.mean indicated pressure C.mean pitch D.middle indicated power D3.The cetane number of a diesel fuel oil indicates its____. A.viscosity B.acid content C.heating value D.ignition quality C4.In a two-stroke engine the camshaft rotates at___the enging rotational speed. A.half B.twice C.the same speed as D.four times D5.A diesel enging is similar to a gasoline engine except that the former has no ____. A.cross-head B.cylinder C.connecting rod D.spark plug C6.It is easier to replace a dry cylinder liner than a wet one because____. A.of the thin wall thickedss B.honing makes it easier to maintain the desired oil film C.water seals are not required D.it fits more loosely due to a decrease in heat transfer through the composite wall D7.A main bearing consists of two shells which are secured by means of studs and____. A.tie rods B.though bolts C.lead wires D.bearing caps C8.However fast or slow the combustion rate,it is still a____between carbon,hydrogen,sulph and oxygen that releases heat. A.physical deformation B.state exchange C.chemical reaction D.coalescence A9.During the fuel injection period,fuel pressure must exceed cylinder gas pressure to____. A.ensure penetration and distribution of the fuel in the combustion chamber B.ensure the needle valves is flushed clean duringeach injection C.prevent combustion gas blowback into the open needle valve Dprevent reflected pressure waves when the neddle valve close. B10.In a diesel engine lube oil system ,which of the following parts should be lubricated first? A.Camshaft bearings B.Main bearings C.Piston crowns D.Cylinder walls B11.In a diesel engine closed freshwater cooling system,the amount of coolant flowing through the heat exchanger is controlled by the _____, A.suction pressure regulator B.thermostatic bypass valve C.sea water temperature D.water level in the expansion tank

轮机大管轮英语真题48期

中华人民共和国海事局 2009年第5期海船船员适任证书全国统考试题(总第48期) 科目：轮机英语试卷代号：803 适用对象：无限、近洋航区3000KW及以上船舶大管轮 （本试卷卷面总分100分，及格分为70分，考试时间为100分钟） 答题说明：请选择一个最合适的答案，并将该答案按答题卡要求，在其相应位置上用2B铅笔涂黑。第1题至82题，每题1分，第83题至94题，每题1.5分。 一、单项选择题： 1. The reason why more and more of the large merchant vessels are being powered by medium-speed diesel engines is . A. they operate between 150 and 450 rpm B. they are connected to the propeller by gearing C. their smaller size and weight D. they can be connected directly to the propeller without gearing 2. The closing of the exhaust valves used on a modern, large, low-speed, main propulsion diesel engine may be directly provided by . A. large conical springs B. compressed air pressure C. hydraulic pressure D. exhaust gas pressure 3. One of the factors limiting the amount of toad which can be put on a modem marine diesel engine is the . A. governor sensitivity B. exhaust temperature C. fuel injection pressure D. speed of the cam shaft 4. The desirable properties or a marine fuel oil should inc lude . A. high flash point and high viscosity B. low flash point and high viscosity C. low heating value and high sulphur content D. high heating value and low sulphur content 5. As the plunger moves upwards in the barrel, injection will commence once the plunger bas the spill ports and the pressure builds up. A. opened up B. closed off C. lined up D. taken off 6. In an auxiliary diesel engine bypass type lubricating oil system, the main lube oil pump forces . A. all of the oil used by the engine through a filter B. some of the oil used by the engine through a filter C. some of the oil used by the engine through a centrifuge D. all of the oil used by the engine through a centrifuge 7. Because the circulating water is in a closed loop, is installed to cater for expansion and contraction of the water at different conditions of operation. A. an expansion joint B. a drain tank C. a head tank D. a contraction tank 8. The high air velocity leaving the compressor of an exhaust gas turbocharger is converted to pressure in the . A. inlet nozzle ring B. turbine wheel blade C. diffuser passages D. inlet volute 9. is usually driven by the engine camshaft and supplies pilot air to the cylinder air start valve. A. An air receiver B. An operating valve C. An automatic valve D. An air distributor 10. Diesel engines driving alternators operating in parallel must maintain a set frequency regardless of load changes. The governor characteristic used to accomplish this is known as . A. actuation B. sensitivity C. compensation D. promptness 11. By comparing the exhaust gas temperature of each cylinder, the operator can determine if the load is balanced throughout the engine. The device most commonly used is a . A. tachometer B. pyrometer C. dynamometer D. calorimeter 12. When the ship is going to enter into the harbor, ____. A. change from heavy fuel oil to diesel oil for main engine B. pumping out bilge water C. change sea chest from high level one to lower level one D. test emergency generator 13. If the jacket water temperature rises rapidly above normal in a diesel engine, you should first . A. place standby cooler in operation B. reduce engine toad C. check thermostatic valve D. clean sea water strainer 14. Air cocks, usually positioned at the in a circulating system, is used to get rid of the air in the system. A. bending joint B. expansion tank C. weld D. the highest point 15. Which of the following conditions could contribute to the cracking of a diesel engine cylinder head? A. Leaking seal ring B. Insufficient heat transfer from the exhaust valves C. Blocked cooling water passages to the head D. Excessive scavenging air provided to the engine 16. of an engine crankshaft can be detected by measuring deflections of' crank webs for each unit of the engine. A. Misalignment B. Length C. Strength D. Stresses 17. can be a direct cause of faulty operation of diesel engine fuel injection nozzles. A. Excessive fuel nozzle holder cooling B. Sediment in the fuel supply C. Distortion of the fuel spray pattern D. Improper atomization of the fuel 18. When fuel is injected late into a diesel engine cylinder . A. the exhaust will be clear B. fuel consumption will be low C. all the fuel will be burned at top dead center D. fuel consumption will be high 19. A large change in ambient temperature, or using an oil of a viscosity different than the one recommended by the manufacturer in a mechanical hydraulic governor, will result m the need to adjust the . A. pilot valve opening B. compensating needle valve C. compensating spring tension D. accumulator spring tension 20. Which of the following factors tends to increase scale formation on the saltwater side of a heat exchanger used in a diesel engine cooling water system? A. Baffle plates that have been bent during prior removal. B. Leaks m the cooler tube nest. C. Operating the engine while maintaining a high sea water outlet temperature. D. A punctured sea water strainer supplying cooling water to the heat exchanger. 21. If the scavenge fire is of a more major nature, if there is a risk of the fire extending or if the scavenge trunk is adjacent to the crankcase with risk of a hot spot developing it sometimes becomes necessary to the engine. A. stop B. start C. speed up D. slow down 22. In an operating diesel engine, which of the following conditions is an indication of a leaking air starting valve?

三管轮轮机英语大证考试真题41期

中华人民共和国海事局 2006年第3期海船船员适任证书全国统考试题(总第41期) 科目：轮机英语试卷代号：805 适用对象：无限、近洋航区3000KW及以上船舶二/三管轮 （本试卷卷面总分100分，及格分为70分，考试时间为100分钟） 答题说明：请选择一个最合适的答案，并将该答案按答题卡要求，在其相应位置上用2B铅笔涂黑。第1题至74题，每题1分，第75题至78题，每题1.5分,第79题至80题, 每题10分。 一、单项选择题 1. A diesel engine is similar to a gasoline engine except that the former has no ______. A. cross-head B. spark plug C. connecting rod D. cylinder 2. A diesel engine which is rated for normal operation at a crankshaft speed of 800 RPM, is commonly classed as a ______. A. slow-speed diesel B. medium-speed diesel C. high-speed diesel D. constant-speed diesel 3.Which of the diesel engine components listed increases air density and helps to improve engine operating efficiency? A. Impeller B. Compressor C. After-cooler D. Exhaust diffuser 4.For a given size engine, the two-stroke/cycle diesel engine will deliver more power than a four- stroke/cycle diesel engine because ______. A. it has a longer power stroke B. more air gets into the cylinder each stroke C. it develops twice as many power strokes at the same speed D. higher combustion pressure is developed 5.The intake valves in a diesel engine are reseated by ______. A. cam followers B. push rods C. combustion gases D. valve springs 6.According to the way the energy of the exhaust gases is utilized, pressure-charging can be divided into two main systems, namely, the constant-pressure system and ______. A. the pulse-phase system B. the pulse Doppler system C. the pulse system D. the pulse interval system 7.An over-speed safety device is usually fitted to a generator engine for______in the event of over- speed. A. cutting power off the engine B. increasing the fuel pump setting C. braking the crankshaft D. stabilizing the ship speed 8.What preventative maintenance should be done frequently to diesel engine starting air receivers? A. Drain the accumulated moisture. B. Test the relief valves. C. Watch the temperature to prevent fluctuations in pressure. D. Clean the interior to remove oil and foreign matter. 9.Immediately after any diesel engine is started, the engineer should check the ______. A. crankcase pressure B. lube oil pressure C. seawater pressure D. exhaust temperature 10. A controllable pitch propeller on a diesel driven vessel eliminates the need for ______. A. friction clutches B. disconnect clutches C. reversing gears D. reduction gears 11.In motor ship, ______is often used to recover some of the heat carried in the exhaust gases from the main engine. A. an diesel oil heater B. a waste heat boiler C. a fresh water generator D. a donkey boiler 12.An exhaust gas bypass is installed on a waste heat boiler in order to ______. A. bypass exhaust gas at high loads to prevent excessive back pressure B. bypass a portion of the exhaust gas at peak loads for better efficiency C. recycle exhaust gas to the turbocharger D. minimize moisture condensation in the boiler gas passages at low loads 13.Prior to lighting off a cold automatically fired auxiliary boiler, you should ______. A. check and regulate the water level B. close the air cock once fires are lit C. blow down the gage glass D. assure protective steam flow 14.Flame failure in an automatically fired auxiliary boiler can mostly result from a/an ______. A. incorrect electrode setting B. incorrect nozzle position C. clogged fuel nozzle D. broken high tension lead 15.Waterside scale in a fire-tube boiler may cause ______. A. increased heat transfer B. fireside erosion C. high steam demand D. overheated tubes 16.Which of the following will be the advantage of a centrifugal pump as compared with a reciprocating pump? I. Its discharge is continuous; II. It has no internal valves; III. Upon accidental closing of discharge valve, excessive pressure will not build up A. I, II B. II, III C. I, II, III D. II only 17.Why are removable sleeves installed on centrifugal pump shafts? A. They make it easier to replace the pump shaft packing. B. They can be economically replaced as they wear out. C. They can be removed when it is necessary to lighten the weight of the pump. D. They increase the strength of the shaft. 18.If one of the bilge system manifold valves does not properly seat, the ______. A. bilge well connected to that valve, plus the second bilge well being pumped will be completely emptied B. bilge system will lose vacuum and prevent the other bilges from being pumped out C. bilge well aft connected to that valve will siphon(虹吸) its contents to the forward bilge wells D. discharge pressure will be too high. 19.Which of the listed statements is correct concerning the starting of centrifugal pumps? A. They should always be started with the discharge valve closed. B. They should always be started with the discharge valve opened. C. A priming pump is always required to flood the impeller suction. D. They should always be started with the sealing line valves closed. 20.The simplest method to use for determining if a centrifugal pump is operating as designed, is to ______. A. closely observe the pump discharge temperature B. close off the discharge valve, and watch for a rise in pressure C. momentarily close off the suction valve, and watch for a rise in pressure D. use a clamp on ammeter and compare the readings to past records

轮机英语历年真题43期

中华人民共和国海事局 2007年第2期海船船员适任证书全国统考试题(总第43期) 科目：轮机英语试卷代号：805 适用对象：无限、近洋航区3000KW及以上船舶二/三管轮 （本试卷卷面总分100分，及格分为70分，考试时间为100分钟） 答题说明：请选择一个最合适的答案，并将该答案按答题卡要求，在其相应位置上用2B铅笔涂黑。第1题至74题，每题1分，第75题至78题，每题1.5分,第79题至80题, 每题10分。 一、单项选择题 1.______ the engines, the diesel engine is ______ used engine on board. A. Between/more commonly B. Among/the most commonly C. Between/not more commonly D. Among/ not the most commonly 2.The average pressure exerted on a piston during each power stroke is termed ______. A. indicated horsepower B. mean effective pressure C. exhaust back pressure D. compression pressure 3.The cetane number rates fuels for diesel engines according to its ______. A. antiknock characteristics B. ignition qualities C. rates of vaporization D. viscosity 4.The time between injection and ignition of the fuel is known as ______. A. turbulence lag B. after burning ratio C. pre-ignition lag D. ignition delay 5.______ controls the fuel oil temperature in order to provide oil at the correct viscosity for combustion. A. The viscosity regulator B. The temperature controller C. The flow meter D. The pressure switch 6.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 7. A device which functions to bring a diesel engine to a full stop to protect it from damage is known as a/an ______. A. torque limiter B. over-speed trip C. over-speed governor D. load limit governor 8.Engine speeds at which resonance can occur are termed ______. A. maximum speeds B. full speeds C. sea speeds D. critical speeds 9.Prolonged operation of a diesel engine with a closed cooling water system at lower than normal designed operating temperatures can ______. A. increase power output B. decrease lube oil viscosity C. eliminate fuel knock D. cause sulfuric acid formation 10.______ on a ship transmits power from the engine to the propeller. A. The automatic control system B. The speed regularly system C. The transmission system D. The compression air system 11.In a _____ boiler the hot gases from the furnace pass through the tubes while the water is on the outside. A. water-tube B. fire-tube C. exhaust gas D. composite 12.The fuel supply system to an automatic auxiliary boiler, will be automatically shutdown if the boiler ______. A.salinity is abnormally B.high steam demand is too high C.feed-water flow is low D.water level is abnormally low 13.The water in a steaming auxiliary boiler should be tested daily for ______. A. dissolved oxygen B. chlorides C. sludge D. dissolved nitrogen 14.Ignition failure in an automatically controlled auxiliary boiler could be caused by ______. A. carbon deposits on the flame scanner B. high fuel oil temperature C. low fuel oil viscosity D. high steam pressure 15.The concentration of total dissolved solids in the water of an auxiliary boiler can increase as a result of ______. A. seawater contamination B. frequent surface blows C. dissolved oxygen de-aeration D. frequent bottom blows

轮机英语试题二十三

试题二十三 一、单项选择题： 1.Because the castings of smaller engines are not so big and heavy, ______ and cylinder block may be made in one piece. A. the column B. the jacket C. cylinder cover D. cylinder liner 2.______ of an engine crankshaft can be detected by measuring deflections of crank webs for each unit of the engine. A. Misalignment B. Length C. Strength D. Stresses 3. A common trouble with the fuel pump plungers or fuel valve spindle is______. A. broken down B. stuck C. oil leakage D. carbonized 4.Diesel fuel oil having a low cetane rating can result in ______. A. improved cold weather starting B. smoother engine operation C. combustion knock D. reduce ignition lag 5.______ is arranged for cleaning the lubricating oil in the system and clean oil can be provided from a storage tank. A. A filter B. A centrifuge C. A distiller D. A generator 6.The emulsion of the oil is mainly caused by ______. A. the solid impurities of large particle B. the solid impurities of fine particle C. the water content D. both water and solid impurities 7.Cylinders of marine diesel engines are normally cooled by ______. A. sea water B. fine mineral oil C. sanitary water D. fresh water 8.______ are fitted in the exhaust system and facilitate charge removal and scavenging in each cylinder. A. Diffusers B. Compressors C. Steam boilers D. Soot blowers 9.______ device is provided to prevent starting air from being admitted to the cylinder before the reversing is completed. A. An automatic B. A transmission C. A self-regulating D. An interlocking 10.The difference between a supercharged engine and an un-supercharged engine is that ______ operates at an increased pressure. A. the later B. the latter C. the former D. the farmer 11.______ for attachment to the propeller shaft also accommodates the turning gear and is integrally forged with the crankshaft. A. The coupling flange B. The camshaft C. The cross-head pin D. The cylinder jackets 12.A(n) ______is a chemical or electro-chemical attack on the metal surface which may be further increased if the sea-water is polluted. A. errosion B. corrosion C. cavity D. scouring 13.The two-stroke cycle begins with the piston coming up from the bottom of its stroke, with scavenge ports in the sides of the cylinder being ______. A. shut B. closing C. opened D. closed 14.The governor of a generator engine is to ______. A. make the engine stop

第46期轮机英语试题

第46期轮机英语试题 一单项选择题 D1. In order to concrol thermal stresses ,some types of modern engines use pistons with __ A heavy wall and intensive cooling B heavy wall and no cooling Cthin wall and no cooling D thin wall and intensive cooling B2. The average pressure exerted on a piston during each power stroke is termed A indicated B ean effective pressure C exhaust back pessure D compression pressure A3. The ignition quality of a diesel fuel is indicated by the___ A cetane number B volatility point C viscosity index Doctane number B4. A piston in a four stroke cycle disesel engine makes four stroke during each __ A crankshaft revolution B mechanical cycle of operation C period of two cobustion cycles D cycle of two events C5. Crankshafts of medium speed engines are _____from a single piece of steel A unusually solid welded B never be solid forged C almost invariably D almost invariably be welded B6 .The starting air entering the cylinder begins when the piston ______ A has nearly come to the TDC B has just past the TDC C has nearly come to the BDC D has just past the BDC D7 .A main bearing consists of two shells which are secured by means of studs and _________ A tie rods B through bolts C lead wires D bearing caps B8 .Compared to four stroke cycle engines ,two ~stroke /cye diesel engines have the disadvantage of ________ A less even torque B higher cylinder head temperatures C fewer power strokes per revolution D greater weight /size requirements A9. _____controls the fuel oil temperature in order to provide oil at the correct viscosity for combustion A The viscosity regulator B The temperature controller C The flow metet DThe pressure switch B10. In a diesel engine lube oil system ,which of the following parts should be lubricated first ? A camshaft bearings B Main bearings C Piston crowns D Cylinder walls C11 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 injectors D12. In a rubocharger ,inlet air velocity is increased in the __________ A inlet nozzle ring B stationary diffuser passages C compressor outlet volute D rotating impeller vanes C13 .Each cylinder has one starting valve which is usually opened by air pressure and closed by _________ A nuts and bolts B new joints C spring force D sealing rings B14. In a simple mechanical governor ,the _________ A centrifugal force rotates the ball-head