winch ratchet wheel

The damage of the derrick was due to the careless handling of the ship's crew in lowering the derrick, causing the topper to override the ratchet wheel and foul onto the topping winch drum shaft.

该吊杆的损坏是由于该轮船员在将吊杆放低时因操作不慎而造成千斤索越过棘轮，缠绕在千斤索绞车卷筒轴上。

互联网摘选