三管轮考证轮机英语4148期试题整理.docx

1、三管轮考证轮机英语4148期试题整理41期一、 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. cylinder2. A diesel engine which is rated for normal operation at a crankshaft speed of 800 RPM, is commonly classed as a _. A. slow-speed

2、 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-strok

3、e/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

4、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

5、B. the pulse Doppler system C. the pulse system D. the pulse interval system7. 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 spe

6、ed 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 af

7、ter 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 g

8、ears 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

9、 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 col

10、d 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 el

11、ectrode 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 centrif

12、ugal 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 pu

13、mp 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 no

14、t 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

15、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 alwa

16、ys 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,

17、 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 21. Which of the following modes of heat transfer does NOT require any physical contact between a warmer and a cooler subs

18、tance? A. Radiation B. Conduction C. Natural convection D. Contact directly 22. A re-heater in an air conditioning system functions to _. A. control inlet air temperature B. control inlet air volume C. maintain relative humidity at 15% D. restore conditioned air temperature to a comfortable level 23

19、. In a chilled water air conditioning unit using a reciprocating compressor, the refrigerating effect of the primary refrigerant can be increased by _. A. increasing refrigerant pressure in the coil B. increasing chilled water flow through the cooler C. sub-cooling the refrigerant in the condenser D

20、. superheating the refrigerant in the compressor 24. Sludge may form in the lubricating oil crankcase of a reciprocating air conditioning compressor as a result of _. A. wax precipitation in the lube oil B. contamination by dust, scale, or moisture C. refrigerant bubbles in the lube oil D. refrigera

21、nt reducing the lube oil viscosity 25. Placing a filter on the _of an oily water separator will “polish” the discharge but overloading must be avoided. A. suction side B. discharge side C. by-pass pipe D. sampling pipe 26. When started, a complete oily water separating unit is first filled _.The oil

22、y water mixture is then pumped through the inlet pipe into the coarse separating compartment. A. with dirty water B. with clean water C. by oily water D. by mixed water 27. Which is the pollution prevention equipment? A. booster pump B. evaporator C. incinerator D. cooler 28. The _is used to burn oi

23、l sludge. A. clarifier B. oil/water separator C. incinerator D. distiller 29. Most marine biological sewage treatment plants consist of all the following statements except _.A. aeration tanks B. settling tanks C. disinfection agent （消毒剂） D. anaerobic bacteria (厌氧菌)30. For a purifier changing to a gr

24、avity disc with smaller hole diameter will move the interface towards the _.A. bowl periphery B. bowl center C. upper surface D. lower surface 31. 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. gravi

25、ty B. diameter C. circumference D. cylinder 32. The advantages of flash type evaporators, as compared to submerged tube type evaporators, include _. A. less internal corrosion because of lower brine density B. higher temperature evaporation for lower salinity of the distillate produced C. less scale

26、 formation in a flash evaporator D. less feed-water required for a flash evaporator 33. Distilled water from an evaporator may be discharged into a drinking water tank _. A. through a detachable hose connection B. after passing through an activated charcoal filter C. after chemical analysis shows it

27、 is fit for consumption D. through a solenoid operated three-way valve 34. What type of valve is used to direct the flow of hydraulic fluid? A. relief valve B. direction control valve C. stop valve D. pressure control valve 35. In a radial piston pump, reversal and control of fluid flow are accompli

28、shed by moving the _. A. central valve B. radial plunger C. floating ring D. cylinder body 36. In a general cargo crane, _is fitted to lift the cargo load. A. the slewing motor B. the luffing motor C. the hoisting motor D. the fan moter 37. _are used to handle anchors and chains. A. Cargo winches B.

29、 Mooring winches C. Windlasses D. Cargo hatches 38. The clutch band of a constant tensioning mooring winch must be set up tight enough to drive the winch drum and should slip only when _. A. excessive loads are placed on the winch B. minimum pull is being exerted by the winch C. automatic operation

30、of the winch is desired D. wire is being retrieved at the maximum rate 39. Dual (双的)electro-hydraulic steering units usually operate _. A. with both pumps on line at the same time Bwith one pump on standby Cwith the follow-up gear disconnected Donly when the rudder is moved amidships40. One factor t

31、hat determines the frequency of an alternator is the _.A. number of turns of wire in the armature coil B. number of magnetic poles C. strength of the magnets used D. output voltage 41. An electrical device which employs a stationary armature and a rotating electromagnetic field is used aboard ship as a _.A. magnetic amplifier B. ships service alternator C. three-wire DC generator D. saturable core reactor 42. Current changing in direction and rising and falling in value is _ . A. D.C. B. A.C. C. generator D. fresh water generator 43