On top of scavenging air box is mounted a strong cast iron frame for each cylinder known as（）

[单选题]On the top of the cylinder is mounted the cylinder cover which is pressed onto （） of the cylinder liner by means of nuts and studs.A . the camshaftB . the flangeC . the ridgeD . the bulge

[单选题]The scavenging air ports are located at （） that they are just exposed by the upper edge of the piston when the piston is in the bottom dead center position.A . so a heightB . such a heightC . so highD . such high

[单选题]If over a period of weeks the air-box pressure of a turbo-charged, diesel engine, operating at full load, appears to be dropping off, the cause can be （）.A . open air-box drainsB . loss of cooling water to the diffuserC . gradual fouling of the air f

[单选题]（） are mounted on and bolted to the bed-plate cross girders.A . The crankshaftB . The crankcaseC . The guide-waysD . The frame

[单选题]Scavenging is （） of exhaust gases by blowing in fresh air.A . the suctionB . the compressionC . the removalD . the deliver

[单选题]Cross scavenging requires the fitting of （） to prevent air or exhaust gas escape when the piston is at the top of the stroke.A . a exhaust valveB . a piston skirtC . a piston crownD . an air suction valve

[单选题]Clearance volume scavenging in a turbocharged, four-stroke/cycle diesel engine is accomplished （）.A . during the valve overlap periodB . with only the exhaust valve openC . at a pressure below atmosphericD . without cooling the cylinders or pisto

[单选题]Some cranes are mounted in pairs on a common platform. which can be rotated through_____.A．360oB．270oC．180oD．90o

[单选题]A-frames are mounted on the bed plate and support （） and cylinder block.A . the main bearingB . the cylinder coverC . the entablatureD . the sum

[单选题]Scavenging in a four-stroke/cycle diesel engine occurs during the （）.A . last part of the exhaust stroke, and the first part of the intake strokeB . last part of the intake stroke onlyC . early part of the injection stroke onlyD . early part of the p