本文总结了起重机大、小车行程限位撞尺设置存在的一些常见问题,分析了因撞尺设置错误而引起的行程开关过早动作、过迟动作或不动作等异常情况可能产生的危害性,阐述了撞尺合理设置需要考虑的三个方面的因素,并从选材、制作、安装等方面,提出了撞尺合理设置的若干要点。 This paper summarizes some common problems existing in the setting of the impact bar of the big and small car travel limit and analyzes the possible harm caused by the abnormal movement of the travel switch such as premature action, late action or no action caused by the wrong setting of the impact bar, The three factors that need to be taken into consideration for the reasonable setting of the impact ruler are expounded. Some points about the reasonable setting of the impact ruler are put forward from the aspects of material selection, manufacture and installation.