单项选择题
A.the crank-web B.the connecting rod C.the main bearing D.the cross-head
The lower end of each piston rod is reduced in diameter...
单项选择题The lower end of each piston rod is reduced in diameter to fit a bore in the cross-head, this being secured to the piston rod by （）.
A.a bolt B.a cap C.a disc D.a nut
单项选择题The lower end of each piston rod is reduced in diameter to fit a bore in the （）, this being secured to the piston rod by a nut.
A.piston gudgeon pin B.piston skirt C.cross-head D.cross-head pin
The loss of （） from an air compressor could lead to an ...
单项选择题The loss of （） from an air compressor could lead to an overheated air discharge and possibly an explosion in the pipelines leading to the air reservoir.
A.lubricating oil B.compressed air C.cooling water D.sealing ring
