随着工业技术的高速发展,起重机械在工农业生产、交通运输以及国防施工中都占有很重要的地位。在起重作业中,由于违章作业或设备本身的缺陷,常发生一些事故。一旦发生事故,往往造成很大损失。从事故原因来看,有的是操作问题,有的同起重机的安全装置不齐全或不灵敏有关。如果有 With the rapid development of industrial technology, cranes occupy a very important position in industrial and agricultural production, transportation and national defense construction. In the lifting operations, due to illegal operations or equipment defects, often there are some accidents. In the event of an accident, it often costs a lot of money. From the point of view of the accident, some are operational problems, and some are not complete or insensitive to the safety devices of the crane. If there is