Design Research For Huge Lift Height Hoisting Mechanism

With the pace of the development of the national economy,demands for large engineering and special equipment have been increased.It requires cranes of particular purpose for lifting and handling the special equipment.In recent years,Gas-Insulated Metal-enclosed transmission Line(GIL)busbar featured of big capacity and small energy consumption has been widely used and applied to the most large-size hydropower stations in China.Generally,GIL busbar is installed inside the silo located between the underground powerhouse and substation on top of mountain.Cranes with super huge lift to complete the installation of GIL are needed.Technical requirements are strict for the lifting height of those cranes in some national hydropower stations.In order to meet precision of installation of GIL,there also are strict requirements on lift & handling tracking of lift device.Most of similar equipment has to be imported from abroad,expensive,long delivery period.Besides,technical blockades have been carried out by overseas enterprises,which urges imminently the national corporations and universities to research on lifting mechanism of these cranes.Through research on key elements of lifting mechanism which affect lifting height and comparison of structure type of lifting mechanism,it has been analyzed and summarized the effects of each element to the components and whole set of cranes for purpose of increasing lifting height.The demand on lifting height of cranes has become larger and larger,for enlargement trend of modern industrial equipment.Increasing the lifting height by simply changing each element can't fulfill the requirements of huge lifting height for modern industrial equipment.To meet the demand of super lifting height,it analyzes and figures out that multilayer winding system should be applied.By comparison of advantages and disadvantages of each type of multilayer winding,it has been concluded that the method of Lebus drum is the one has the advantages of the most.Technology of Lebus drum has become advanced for it has been more and more widely applied into industrial application.However,phenomenon of rope disorder on the drum still exists in operation and application.As insufficient study on wire rope's winding and climbing on Lebus drum,it illustrates ideal winding trajectory when the wire rope climbs and reverses on Lebus drum by mathematical model,and builds model of blocking rings of climbing and rotating on Lebus drum.Subjected to the above study results,the paper introduces lifting mechanism with lifting height up to 280 m and completes detailed designing of Lebus drum.Multilayer winding on Bi-Lebus drum has been adopted to the lifting mechanism.This kind of lifting mechanism has been applied on EOT Cranes Project of Xiluodu Hydropower Station,supplied by Taiyuan Heavy Industry Co.,Ltd.,(mentioned as “Xiluodu project”)which can effectively meet the installation requirements of GIL for domestic hydropower stations and realize huge lifting height and precision location.With utility of this kind lifting mechanism on lifting GIL,it not only can improve installation accuracy,but also greatly shorten installation cycle.The lifting mechanism has been successfully operated on the cranes of Xiluodu project and feasibility of designing has been tested and verified by engineering practice.The success to study on this kind lifting mechanism makes similar equipment can be manufactured on China's own.