Telescopic pipes to the piston of a large slow-speed main propulsion diesel engine are designed to prevent （）.

[单选题]People with disabilities comprise a large part of the population. It is(C1)______ that over 35 million Americans have physical,(C2)______ , or other disabilities. About half of these disabilities are "developmental", i.e., they(C3)______ prior to t

[单选题]The reason why more and more of the large merchant vessels are being powered by medium-speed diesel engines is .A．they operate between 150 and 450 rpmB．they are connected to the propeller by gearingC．their smaller size and weightD．they can be connect

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

[单选题]F．or what purpose are the diving pipes used?A． To absorb heat from the sun.B． To store heat for future use.C． To turn solar energy into heat energy.D． To carry heat down below the surface.

[单选题]The lubricating pipes and dusts should be blown out with （）.A . atmosphereB . the fresh waterC . compressed airD . chemical compound

[单选题]The fuel pipes and ducts should be blown with （）.A . atmosphereB . the fresh waterC . compressed airD . chemical compound

[名词解释] 管道防腐（corrosion preventive of pipes）

[单选题]As to the piston cooling, of the following, which statement is not true?（）A . Because the piston is exposed to very high temperature, it must be cooledB . The lower the piston cooling temperature is, the better it isC . Both water and lube oil can be

[单选题]The piston rings are manufactured with a diameter （） the bore of the cylinder.A . larger thanB . smaller thanC . equal toD . none of the above

[单选题]The lowest ring of a piston is （）.A . a coil springB . a sealing ringC . an oil distributor ringD . main seal ring