轮机英语试题二十五

试题二十五

一、单项选择题：

1.In an ordinary diesel engine the fuel injection begins ______.

A. after TDC

B. before TDC

C. after BDC

D. before

BDC

2.The supercharger takes air out of the surrounding atmosphere and then feeds it to the

engine's___.

A. inlet valves

B. exhaust valves

C. emergency valves

D. non-return valves

3.With supercharging a larger mass of air is supplied to the cylinder by blowing it in under

pressure, which is the best means to ______of the engine.

A. increase the exhaust temperature

B. increase the power

C. reduce the speed

D. increase the fuel consumption

4.Additives ______protective layers on metal surfaces guarding them against corrosion.

A. damage

B. form

C. dissolve

D. contaminate

5.When fuel oil has seriously contaminated a diesel engine lubricating oil, you should ______.

A. filter to remove the fuel oil

B. use the settler to remove the fuel oil

C. remove the fuel oil by centrifuging

D. drain and then renew the lube oil supply

6.About half an hour before the engine is required, cooling water at ______must be circulated

in principle.

A. more than the working temperature

B. less than the working temperature

C. the working temperature

D. the same as the surrounding

temperature

7.The lubricating system for the cylinder walls is different from the bearings in that the oil for

former one is supplied in ______while that for latter one is ______.

A. sufficient quantity / measured

B. measured quantity/ sufficient

C. excessive quantity/ sufficient

D. the less quantity the better/the more the better

8.The tendency for lubricating oil to thin out at high temperatures and thicken at low

temperatures will be characterized by a ______.

A. low viscosity index

B. high viscosity index

C. high neutralization number

D. low demulsibility quality

9.Emulsion oils and sodium nitrite are both approved additives, but the latter cannot be used if

any pipes are ______or if any soldered joints exit.

A. chromed

B. welded

C. galvanized

D. bolted

10.In the event of the cylinder starting valve leakage ______would pass into the air pipes and

ignite the oil deposited.

A. cooling water

B. vapor from the boiler

C. starting air

D. hot gases

11.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

12.______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

13.The power output of a turbocharged diesel engine will drop if the cooling water flow through

the after-cooler is interrupted because the ______.

A. turbocharger stalls

B. exhaust pressure increases

C. air charge density decreases

D. scavenge effect increases

14.An electrically driven automatically operating auxiliary blower is provided for slow speed

and ______of a low speed diesel engine.

A. manoeuvring operations

B. bad combustion

C. cooling

D. mooring trial

15.The volute pump is one in which the impeller ______.

A. discharges into a gradually widening channel

B. has stationary diffuser vanes

C. produces no kinetic energy

D. All of the above

are true.

16.When operating with a negative suction head, which of the following types of pumps will

require priming?

A. Reciprocating

B. Centrifugal

C. Rotary

D. Gear

17.In reference to air conditioning, when air attains the maximum amount of moisture it can

hold at a specific temperature, that is said to be ______.

A. superheated

B. saturated

C. condensed

D. convected

18. A simple pumping system consists of a suction branch, a pump and______.

A. a priming device

B. a discharge branch

C. a filter

D. a suction valve

19.The fire pumps must be capable of delivering a total quantity of water at a defined head , no

less than ______of the total bilge pumping capacity.

A. one-third

B. two-thirds

C. one-fourth

D.

two-fourths

20.Most marine biological sewage treatment plants consist of all the following statements except

___.

A. aeration tanks

B. settling tanks

C. disinfection agent

D. anaerobic

bacteria

21. A donkey boiler is ______.

A. one to supply steam to the main propulsion turbine

B. an auxiliary boiler

C. A and B

D. neither A nor B

22.Excessive vibration of an automatically fired auxiliary boiler can be caused by ______.

A. air or water in the furnace

B. combustion pulses

C. fuel oil pump failure

D.

flame failure

23.The amount of moisture in a given sample of air, when compared with the amount of

moisture the air could hold if totally saturated at the existing temperature of the sample, is called ______.

A. absolute humidity

B. specific humidity

C. effective humidity

D. relative

humidity

24.High-speed rotation in a centrifugal purifier can produce a force ______the force of gravity.

A. many thousand times larger than

B. the same as

C. many thousand times smaller than

D. none of the above

25.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

26.If air at 95 ℃dry bulb temperature and 50% relative humidity is conditioned to 75 ℃dry

bulb temperature and 50% relative humidity, it is an example of ______.

A. cooling only

B. cooling and humidifying

C. cooling and dehumidifying

D. adiabatic

cooling

27. A class ‘C ’fire would occur in ______.

A. bedding

B. pipe insulation

C. paint

D. a

generator

28.In a hydraulic system, ______are used to protect the system from over pressure.

A. stop valves

B. check valves

C. safety valves

D. reducing valves

29.What color is used to indicate the last shot of anchor chain?

A. Red

B. White

C. Blue

D.

Yellow

30.An axial piston pump differs from a radial piston pump as the pistons of an axial piston pump

are positioned______.

A. radially from the shaft

B. parallel to each other and to the shaft

C. parallel to each other but at a right angle to the shaft

D. at an angle to each other and to the shaft

31.Which is the pollution prevention equipment?

A. booster pump

B. evaporator

C. incinerator

D. cooler

32.In a vacuum boiling evaporator, the fresh water generated is pumped out by ______.

A. a brine pump

B. an air ejector

C. a feed water pump

D. a condensate

pump

33.The cooler as the liquid becomes, ______.

A. the faster it will evaporate

B. the slower it will condense

C. the slower it will evaporate

D. the faster it will flow

34.Sludge may form in the crankcase of an air conditioning compressor as a result of ______.

A. bubbling refrigerant

B. overheating and oxidation

C. lowered operating temperatures

D. reducing the cloud or flash point

35.Differential pressures can be measured with the use of a ______.

A. diaphragm type gage

B. pressure transducer

C. manometer

D. all of the

above

36.If the suction pressure at the refrigeration compressor is below normal, the cause can be

______.

A. refrigerant overcharge

B. overfeeding by the expansion valve

C. a restricted suction strainer

D. due to short cycling of the compressor

37.The staring current of an a.c. motor is ______the rated current.

A. the same as

B. much larger than

C. less than

D. equals

38.You are attempting to parallel two AC generators and the synchroscope pointer is revolving

in the slow direction. This indicates that the frequency of the incoming machine is ______.

A. higher than the bus frequency

B. lower than the bus frequency

C. the same as the bus frequency but out of phase with it

D. the same as the bus frequency, and the circuit breaker may be closed at any pointer

position

39.The main generators are connected to ______.

A. distribution boards

B. section boards

C. emergency switch boards

D. main

switch boards

40.The switchboards for A .C. systems differ from the D.C. switch gear in that the open type

panels are generally ______and the dead-front switch gear is the common rule.

A. permissibly

B. permissible

C. no permissible

D. not

permissible

41.Temperature measurement by instruments will give a value in degree Celcius. This scale of

measurement is normally used for all readings and temperature values ______dealing with theoretical calculations involving the gas laws.

A. in addition to

B. in addition that

C. except that

D. except when

42.This arrangement is ______if the elements are directly connected to one another and the

control action takes place without human involvement.

A. a manual closed loop

B. a manual opened loop

C. an automatic closed loop

D. an automatic opened loop

43.The viscosity regulator controls the fuel oil temperature ______provide oil at the correct

viscosity for combustion.

A. in order that

B. because of

C. in order to

D. owing to

44.The resistance of electric wire will decrease as its ______.

A. length increases

B. cross-sectional area increases

C. temperature increases

D. percent of metallic purities increases

45.An accidental path of low resistance, allowing passage of abnormal amount of current is

known as a/an ______.

A. open circuit

B. short circuit

C. polarized ground

D. ground reference

point

46.Main diesel engine control can be obtained by the bridge ______.

A. at any time

B. only after the engine room control station is switched to ‘bridge control ’

C. whenever the secondary station is switched to ‘bridge control ’

D. whenever the engine side control station is switched to ‘bridge control ’

47.Which of the following statements represents the main difference between a relay and a

contactor?

A. Contactors control current and relays control voltage.

B. A relay is series connected and a contactor is parallel connected.

C. Contactors can handle heavier loads than relays.

D. Contactors are made from silver and relays are made from copper.

48.Piston No. 2 of main engine has been removed, and it will be ______by noon tomorrow.

A. lifted

B. reassembled

C. dismounted

D.

disassembled

49.Defective air cooler in a diesel engine will lead to:

A. smoky exhaust

B. starting failure

C. overload

D. over speed

50.If the jacket water temperature of an operating diesel engine suddenly rises above normal, the

cause can be attributed to _____________.

A. an overfilled expansion tank

B. excess chromate(铬酸盐) treatment of the jacket water

C. a clogged raw water sea suction

D. cavitation erosion of the heat exchanger tubes

51.The bearing cap and shell are replaced and tightened up until ______.

A. the “nip ”is zero

B. the “nap ”is zero

C. the “gap ”is correct

D. the “clearance ”is correct

52. A diesel engine is operating with excessively high exhaust temperatures at all cylinders. To

correct this condition, you should first______.

A. reduce the engine load

B. increase the cooling water flow

C. increase the lube oil pressure

D. adjust the fuel rack

53.If exhaust temperatures are too high, you should check ______.

A. air cooler

B. turbocharger

C. charge air

D. A+B+C

54.______, the engine must be stopped immediately.

A. Should knocking occur

B. If knocking occur

C. Should if knocking occurs

D. If occur knocking

55.Lower suction pressure of a pump may be caused by ______.

A. too much air in the pipe line

B. clogged strainer

C. empty tank

D. leaky

pipe

56.Each journal and pin should be examined for ______and grooving.

A. bridges

B. recesses

C. rears

D. ridging

57. A water pump can not supply water after starting. It may be caused by ______.

A. closed discharge valve

B. broken pipe line

C. worn shaft

D. both A and

B

58. A centrifugal pump can’t supply water after starting. You should check ______.

A. inlet valve

B. power supply

C. packing gland

D. bearing lubrication

59.When starting a centrifugal pump, the discharge valve should be ______.

A. closed

B. opened fully

C. cracked open

D. partly open

60.It is well known that the whole power distribution of the ship’s electrical services mainly

depend on the ______.

A. sub-boards

B. main switchboards

C. emergency switchboards

D. distribution

boards

61.The order“Bow thrust stop.”means“______”.

A. Bow thrust full to port

B. Bow thrust full to starboard

C. No bow thrust revolutions

D. No stern thrust revolutions

62.When start a screw pump, the by pass valve should be ______.

A. closed

B. opened fully

C. cracked open

D. partly open

63.All engineer officers and engine room ratings shall be aware of the serious effects of

operational or accidental pollution of the marine environment and shall take all possible

______to prevent such pollution, particularly within the framework of relevant international and port regulations.

A. steps

B. procedures

C. precautions

D. programs

64.The fire of electrical equipment is classified as ______fire.

A. Class A

B. Class B

C. Class C

D. Class D

65.If you must enter a room or compartment to combat the fire , keep an escape path ______.

A. open

B. close

C. opens

D.

closes

66.The stability of a vessel is normally the greatest when all fuel and water tanks are full

because the ______.

A. center of gravity is lowered

B. center of buoyancy is lowered

C. reserve buoyancy is unchanged

D. hull freeboard is increased

67.After fuel tanks have been topped off, which of the listed procedures should be followed next?

A. The pressure-vacuum relief valve should be reset.

B. The tanks should be made seaworthy to prevent contamination.

C. The tanks should be sounded to make sure the levels are not rising.

D. The tanks should be marked with a bull stamp on the manifold filling valve

68.______may have two emergency source of power, thus requiring two emergency

switchboards.

A. Large passenger vessels

B. General cargo ships

C. Container ships

D. Oil

tankers

69.________may have two emergency source of power, thus requiring two emergency

switchboards.

A. Large passenger vessels

B. General cargo ships

C. Container ships

D. Oil

tankers

70. A ______sometimes called filters, is a device designed to prevent the passage of unwanted

solids into the system.

A. Steam trap

B. Check valve

C. Separator

D. Strainer

71.In cleaning up an oil spill, the use of chemical agents would ______.

A. absorb the oil for easy removal

B. remove the oil from the water

C. disperse or dissolve the oil in the water

D. not affect the oil

72.Which fire fighting agent has the greatest capacity for absorbing heat?

A. water

B. dry chemical

C. foam

D. CO 2

73.Why is it important for fuel oil tanks not to be topped off at the inner bottom level when

loading on a cold day?

A. Increased viscosity of the product needs higher loading pressure, which increases the

chances

of a spill.

B. Air pockets may cause the fuel to bubble out of the ullage hole.

C. The temperature rise of the fuel will cause an overflow.

D. Fueling valve may become stuck closed and cause the fuel oil to spill before the valve can

be

opened.

74.The possibility of damage from operating a diesel engine at critical speeds is reduced by the

use of ______.

A. an isochronous(同步的) governor

B. elastic(弹性的) engine mounts

C. a vibration damper

D. a cast iron bed plate with good

flexible qualities

二、关联题（每组关联题题干下有4个小题，每小题4个选项）

Severe damage has been caused by “water hammer”when steam has been admitted to pipes containing water, especially when the run of the pipe, e.g. ,being inclined only slightly from the horizontal , allowed the water to have a large free surface area; this is the important point.

On steam being admitted, condensation occurs on the cool water surface, a partial vacuum develops and the water moves along the pipe at great speed :if arrested by a bend or a closed valve, very large hydraulic forces are generated and fracture follows. It should be apparent that little or nothing is gained by opening a drain at the same time as or after admitting steam.

It is thus imperative that steam pipes be left draining when not in use and that master valves be first eased off their seats or “cracked “when a line is being brought into use until the pipe is thoroughly warmed. Only then should the valve be opened fully.

75.The phrase “water hammer” means ______.

A. the hammer is made of water

B. the drainage water

C. the steam condensed water in the pipes

D. the high speed in the pipe the steam condensate flows

76.The word “this” in line 3 of the first paragraph probably refers to______.

A. water hammer

B. steam

entering piping

C. the situation described in the first sentence

D. the water having a large free surface

area

77.According to this passage, we can not infer that______.

A. the water in the pipe has very high pressure

B. steam that meets the cool water surface will condense

C. the bend or a closed valve will prevent the water from moving

D. it is necessary to drain the water in the piping when admitting the steam

78.The word “cracked”in line 6 of the second paragraph probably means ______.

A. the master valves have been fractured

B. the seats of the valves have been broken down

C. the pipes and the valves have defects

D. the master valves should have a slight

opening

三、中译英（共2题，请将答案写在答题纸上）

79. 一个安全阀送车间解体、检查和研磨。

80. 根据轮机长指示，左舷二号舱燃油驳至右舷五号舱。