Each cylinder liner on the marine medium speed engines _____.A.is usually cooled by sea waterB.can be replaced when worn outC.is in direct contact with the water in the bore of the cylinderD.can t expand when heated

题目

Each cylinder liner on the marine medium speed engines _____.

A.is usually cooled by sea water

B.can be replaced when worn out

C.is in direct contact with the water in the bore of the cylinder

D.can t expand when heated

相似考题

1.Metals ______ when they are heated.A.extendB.enlargeC.spreadD.expand

2.A crack in a cylinder liner can be caused byA.worn piston ringsB.installation of undersized sealing ringsC.operating the engine at low loadsD.restricted cooling water passages

3.Low compression in a diesel engine could be caused byA.worn or broken cylinder liner sealing ringsB.high cooling water temperatureC.worn or broken piston ringsD.low fuel oil pressure

4.When water( ), it will be changed into vapour.A. is heatedB. was heatedC. will be heatedD. would heated

更多“Each cylinder liner on the marine medium speed engines _____.A.is usually cooled by sea waterB.can be replaced when worn outC.is in direct contact with the water in the bore of the cylinderD.can t expand when heated”相关问题

  • 第1题：

    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&39; 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 head

    B.several injectors mounted around the external boundary of the cylinder head

    C.a single injector mounted at the external boundary of the cylinder head

    D.several injectors mounted in the center of the cylinder head


    正确答案：B

  • 第2题：

    单选题
    Insufficient end clearance on newly fitted piston rings in a diesel enginewill cause the rings to（）
    A

    jam in the most worn part of the cylinder when the rings expand

    B

    break in the most worn part of the cylinder when the rings expand

    C

    wear eccentrically on the side opposite the end gap

    D

    overheat and jam at the top center on the combustion stroke


    正确答案： C
    解析： 暂无解析

  • 第3题：

    单选题
    What is the operating principal of a flash type evaporator?（）
    A

    Sea water is heated to boiling temperature under a vacuum

    B

    Sea water is passed over heated plates in a thin film

    C

    Heated sea water is injected into a vacuum chamber

    D

    Sea water is forced through a heated eductor


    正确答案： A
    解析： 暂无解析

  • 第4题：

    单选题
    In a medium speed diesel engine, a trunk type piston may be cooled by（） Ⅰ.oil circulation though passages in the piston crown Ⅱ.heat transfer through piston rings and liner wall
    A

    Ⅰ only

    B

    Ⅱ only

    C

    either Ⅰ or Ⅱ

    D

    neither Ⅰ or Ⅱ


    正确答案： D
    解析： 暂无解析

  • 第5题：

    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.
    A

    slope

    B

    base

    C

    top

    D

    bottom


    正确答案： C
    解析： 暂无解析

  • 第6题：

    单选题
    Cylinders of marine diesel engines are normally cooled by （）.
    A

    sea water

    B

    fine mineral oil

    C

    sanitary water

    D

    fresh water


    正确答案： D
    解析： 暂无解析

  • 第7题：

    单选题
    When used with reversing reduction gears, medium-speed diesel engines should be bolted to their foundations with fitted bolts at the drive end and clearance(loosely fitted) bolts in other locations √This is done to （）
    A

    maintain alignment when the ship’s hull is working in heavy seas

    B

    ensure engine vibrations correspond to the natural frequency of the hull

    C

    permit the engine to expand away from the driven equipment as the engine heats up and expands

    D

    maintain engine thrust bearing clearances


    正确答案： A
    解析： 暂无解析

  • 第8题：

    单选题
    When good and steady service conditions have been achieved, the running surfaces of the piston rings and cylinder liner will be（）In addition, the rings will move freely in the grooves and also be well oiled intact, and not unduly worn.
    A

    hazy light

    B

    hazy light brown

    C

    hazy light blue

    D

    hazy light grey


    正确答案： C
    解析： 暂无解析

  • 第9题：

    单选题
    The bore of each cylinder is formed in a liner which can be （） when worn out.
    A

    welded

    B

    replaced

    C

    drilled again

    D

    bored


    正确答案： B
    解析： 暂无解析

  • 第10题：

    单选题
    Trunk type diesel engine pistons are effectively cooled when heat is（）
    A

    radiated through the engine block

    B

    transferred to water cooled cylinder walls

    C

    conducted through the piston crown

    D

    transferred to escaping exhaust gases


    正确答案： D
    解析： 暂无解析

  • 第11题：

    单选题
    The cooling water is in direct contact with the outer surface of the liner as a result of which it is termed a （）.
    A

    water liner

    B

    wet liner

    C

    dry liner

    D

    drown liner


    正确答案： B
    解析： 暂无解析

  • 第12题：

    单选题
    The rate of cylinder lubricating oil metered to each cylinder of a large low-speed main propulsion diesel engine is （）
    A

    the same, whether at sea, or during maneuvering

    B

    adjusted during each hour of operation while at constant RPM

    C

    higher at sea than while maneuvering

    D

    lower at sea than while maneuvering


    正确答案： C
    解析： 暂无解析

  • 第13题：

    Cylinders of marine diesel engines are normally cooled by ___ .

    A.sea water

    B.fine mineral oil

    C.sanitary water

    D.fresh water


    正确答案：D

  • 第14题：

    单选题
    In large marine diesel engines cylinder oils usually contain additives formulated to impart the （） to clean the rings and grooves.
    A

    inefficiency

    B

    oiliness

    C

    detergency

    D

    purity


    正确答案： A
    解析： 暂无解析

  • 第15题：

    单选题
    Each cylinder liner on the marine medium speed engines （）.
    A

    is usually cooled by sea water

    B

    can be replaced when worn out

    C

    is in direct contact with the water in the bore of the cylinder

    D

    can t expand when heated


    正确答案： A
    解析： 暂无解析

  • 第16题：

    单选题
    The majority of medium speed and high speed marine diesel engines for main or auxiliary drive operate on the （） cycle.
    A

    two-stroke

    B

    four-stoke

    C

    long-stroke

    D

    short-stroke


    正确答案： B
    解析： 暂无解析

  • 第17题：

    单选题
    The cylinder liner forming the cylinder wall and the inside of the water jacket is called a（）
    A

    dry liner

    B

    wet liner

    C

    jacket liner

    D

    corrugated liner


    正确答案： A
    解析： 暂无解析

  • 第18题：

    单选题
    Which of the following statements is correct concerning diesel engine cooling water systems?（）
    A

    Each engine must have its own engine driven cooling water pump capable of providing cooling for all ranges of operation

    B

    propulsion engines with bores exceeding 200 mm are to be fitted with a means to display the cooling water temperature of each cylinder

    C

    At least two independent sea suctions are to be provided for supplying water to the engine jackets or to the heat exchangers

    D

    Suitable strain are to be fitted between the circulating pumps and heat exchangers when sea water is used for direct cooling


    正确答案： B
    解析： 暂无解析

  • 第19题：

    单选题
    Allowance for fresh water refers to（）.
    A

    the provision to be provided when the vessel sails in fresh water area

    B

    the fresh water to be carried by a vessel

    C

    the allowance of fresh water for each crew member when in distress at sea

    D

    the amount of free board decreased when sailing in fresh water area


    正确答案： D
    解析： 暂无解析

  • 第20题：

    单选题
    Which of the following procedures should be carried out when a large, low-speed, diesel engine is operated with one cylinder secured?（）
    A

    Lubrication to the defective cylinder should be increased

    B

    Cooling water temperature to the engine should be increased

    C

    Only the turbocharger speed should be reduced

    D

    Engine speed should be reduced


    正确答案： B
    解析： 暂无解析

  • 第21题：

    单选题
    Cooling water pumps driven by direct reversing diesel engines are usually of the straight impeller vane type pump with a concentric housing to（）
    A

    facilitate bi-directional operation

    B

    provide the greatest pump efficiency

    C

    prevent pump clogging from marine growth

    D

    prevent cavitation at the pump outlet


    正确答案： B
    解析： 暂无解析

  • 第22题：

    单选题
    Pistons of marine medium speed diesel engines may be made of （） in order to keep the weight down for balancing purpose at high speed.
    A

    lead

    B

    forged steel

    C

    alloy steel

    D

    aluminum alloy


    正确答案： B
    解析： 暂无解析

  • 第23题：

    单选题
    Cylinder lubrication oil for low speed main propulsion diesel engines is admitted to each cylinder during （）.
    A

    the power stroke

    B

    the compression stroke

    C

    low load operation only

    D

    periods of standby


    正确答案： D
    解析： 暂无解析

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