造船龙门起重机是一种水平桥架设置在刚、柔两条支腿上构成的门架形状的起重设备，主要用于船坞拼装船体。
The gantry crane that works in the shipyard is a horizontal-bridge lifting equipment , which is made up of a stiff leg and a flexible leg . It is mainly used for assembling hulls in the dock .
柔条