97免费在线观看视频,亚洲综合自拍网,黄色毛片免费观看,热久久综合网,免费看日产一区二区三区 狠狠操av,久久久涩涩涩,在线精品免费视频,人人插天天干,久久91精品国产91久久

單項(xiàng)選擇題

In an engine with a pot-shaped piston, some lubricating oil from the main bearing will pass along a drilled passage in the crankshaft to the bottom end bearing and then up a connection rod to the ().

A.crosshead
B.crankpin
C.crank journal
D.gudgeon pin

微信掃碼免費(fèi)搜題