使用二次限位断电装置防止炼钢天车吊具冲顶韶关钢铁集团公司蒙高光，许绍林，王权柱炼钢生产作业中天车使用频繁，加上高温环境，易使天车吊具在天车控制主回路发生故障时，失去控制，限位器无法实现限位作用。韶钢每年因过卷冲顶撞烂天车滑轮，断裂钢丝绳则不少，设备遭... Use the second limit power-off device to prevent steel cranes hoisting overhead Shaoguan Iron and Steel Group Menggao Guang, Xu Shaolin, Wang Quanzhu steel production operations in the frequent use of overhead traveling vehicles, coupled with high temperature environment, easy to make Crane spreader Car control main circuit failure, loss of control, limiter can not achieve the limit role. Shaogang every year due to roll over the top crash bad car pulley, broken rope is a lot of equipment is ...