The piston rings are manufactured with a diameter （） the bore of the cylinder.

[单选题]The piston rings if found worn out （） and supplied by shipchandler.A . must replaceB . must to be equippedC . has to be repairedD . have to be renewed

[单选题]Among the rings of a piston the （） one is subjected to the greatest load and temperature.A . bottomB . middleC . topD . none of the above

[单选题]These piston rings are so badly worn that they must be （）.A . renewedB . weldedC . machinedD . chromium-plated

[单选题]The upper piston rings m large, slow-speed, two-stroke/cycle diesel engines are most effectively lubricated by oil ____.A．fed from mechanical lubricatorsB．thrown off from the main bearingsC．supplied from wick fed drip lubricatorsD．flow from a centrif

[单选题](piston area)×(piston stroke)×(numbers of the cylinders)=engine( ).A．brake horsepowerB．displacementC．cylinder volumeD．cylinder clearance

[单选题]Thiskindofglassesmanufacturedbyexperiencedcraftsmen______comfortably.A)iswornB)wearsC)wearingD)areworn

[单选题]The sealing rings are in four parts and pressed together around the piston rods by means of _____A．nutsB．boltsC．coil springsD．stuffing boxes

[单选题]The sealing rings are in four parts and pressed together around the piston rods by means of （）.A . nutsB . boltsC . coil springsD . stuffing boxe

[单选题]The film of oil between the rings and the liner is not only essential for the lubrication but also plays an important part in achieving （）.A . an oil sealB . removing heatC . a gas sealD . cooling the pisto

[单选题]All the rings are slightly rounded on their external top and bottom edges to keep the oil film on the cylinder liner during （） for new piston rings.A . the running-in periodB . the running processC . gas exchange processD . the boiler firing