The bridge across the track or on the shelf, the best frame is bearing surface of leg link on the standard level measured at both ends of the bearing surface on the trolley track.

将桥架横放在轨道上或架子上，最好架在于支腿链接用的支承面上，用水平仪测出两端支承面上边的小车轨道的水平标准。

youdao

When the door frame is seriously distorted, the main beam, the supporting legs, the lower beam, the trolley and the connecting piece of the frame can bear large distortion stress.

在门架严重扭曲时的主梁、支腿、下横梁、台车及他们之间的连接件均会承受很大的扭曲应力。

youdao

The four corners of the frame are provided with four pulleys. Wire ropes pass round the pulleys and are tightened on the reel drum of a crane trolley.

框架上面的四角装有四只滑轮，钢丝绳绕过滑轮向上系于起重行车的卷筒上。

youdao