单项选择题
A.shim B.gasket C.washer D.packing
Pistons of marine medium speed diesel engines may be ma...
单项选择题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
Pistons may be made in （） in order to keep the weight d...
单项选择题Pistons may be made in （） in order to keep the weight down for balancing purposes at high speed.
A.cast iron B.forged steel C.stainless steel D.aluminum alloy
Piston No2 of main engine has been removed, and it will...
单项选择题Piston No2 of main engine has been removed, and it will be （） by noon tomorrow.
A.lifted B.reassembled C.dismounted D.disassembled
