Cracks in cylinder and cylinder covers may （） from unequal heating.

[单选题]The cylinder covers and the liners are bolted together by means of （）.A . bolts welded into the cylinder headB . bolts welded into the cylinder framesC . studs screwed into the cylinder headD . studs screwed into the cylinder frame

[单选题]The cylinder head, cylinder liner and （） form the combustion chamber.A . frameB . pistonC . crankcaseD . explosion plate

[单选题]（） is used for cylinder and cylinder head, the salt water is used for cooling the lubricating oil, the fresh water in the coolers and the charging air in the air cooler.A . The fuel oilB . The lube oilC . The sea waterD . The fresh water

[单选题]Cylinder lubrication oil for low speed main propulsion diesel engines is admitted to each cylinder during （）.A . the power strokeB . the compression strokeC . low load operation onlyD . periods of standby

[单选题]The cylinder cover is not provided with ( )A．fuel valveB．the starting valveC．lubricator

[单选题]The cylinder liners are made of _____ and the cylinder surfaces are sometimes chromium-plated.A．steelB．copperC．cast ironD．stainless steel

[单选题]The withdrawing of the cylinder liners, in general, depends on their （）.This may amount to approximately 1/120 of the diameter in some engines.A . correct maneuveringB . wearC . working efficiencyD . maintenance

[单选题]The cylinder cover is not provided with （）.A . fuel valveB . lubricatorC . indicator valveD . the starting valve

[单选题]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； measuredB . measured quantity；sufficientC . excessive quantity；suff

[单选题]E．ach cylinder is closed at the top by a _____, made of a special heat-resistant steel.A．cylinder linerB．coupling flangeC．cylinder coverD．piston crown