Взаимодействие элементов телескопической стрелы в результате внезапного снятия нагрузки

Abstract

Nowadays, self-propelled jib cranes equipped with telescopic jib equipment are widely used in construction, loading, unloading and installation works. Accidents of self-propelled jib cranes caused by a sudden break of a cargo rope, as well as spontaneous unloading of cargo, can be attributed to the main causes of accidents of hoisting cranes. This reason can be considered as one of the most dangerous, since sudden release of the load is characterized by unpredictability, independence from the skill of the operator and the transience of the impact. The aim of the work is to study the loading of telescopic boom equipment during sudden load removal and to propose measures to prevent or reduce the consequences of accidents caused by this type of loading. The railway crane “Sokol 80.01M” was selected as the object of study. The method of numerical experiment, carried out in the module of complex dynamic and kinematic analysis of SolidWorks Motion mechanisms was used as a research method. As a result of numerical simulation of instantaneous load removal, balancing of the telescopic boom on the sliding plates and shock interactions of the boom sections were established. The following parameters were determined: the time dependence of the sliding support reactions, the magnitude of shock interactions, and the time dependence of the boom head vibrations. It is proposed to use on a self-propelled jib cranes the “Method to increase the safety and security system of a jib crane”, which, in addition to protecting the crane from overload and from collisions of its boom or load-lifting body with various obstacles (coordinate protection), due to the presence of pyro-cartridges and their control subsystem, ensure the prevention of accidents in the event of a sudden removal of the load from the boom, as well as the protection of the hoisting machine when exposed to random external factors, damage reduction with irreversible loss of stability of the crane. The most rational parameters of the emergency power device for boom equipment were established: the time of action of the squib; the action coefficient of the squibs, the initial force of the squibs, the charge force of the emergency power device on the boom equipment.