The Application Design Of Ultra High Strength Alloy Steel Crane Truss With FZQ2000Z Type Tower Crane

With the continuous progress of science and technology,the structure of the boom tower is gradually developing to a large scale,and the weight and working speed are constantly improved.Cantilever crane as an important supporting structure of crane,its weight occupies a large proportion in the whole machine,and excessive self-weight will seriously affect the crane's lifting capacity.In recent years,in order to reduce the weight of crane boom and improve the performance of the whole machine,people have begun to use lightweight high strength alloy steel for the boom of crane boom.But in most cases,the structure of the truss does not make full use of the properties of the material.In view of the above problems,this paper has done the following research work:The structure and working principle of the truss type arm frame of the FZQ2000Z type boom tower crane are studied.The load distribution of the arm frame's amplitude plane and the rotary plane is discussed.The force characteristics of the arm frame are studied,and the length and the pitch of the arm frame when the stability of the crane arm is the worst is determined.With the ANSYS finite element software,the finite element analysis model of the arm frame structure under the condition of multi load combination is established,and the maximum bearing capacity and maximum failure lifting weight of the arm are analyzed when the worst stability is analyzed.By the improvement of the string structure,the lightweight high strength alloy steel D562 is replaced by the ordinary steel Q390,and the analysis is made.The elastoplastic mechanical properties of the time arm frame determine the maximum utilization of the strength of the arm and the abdominal rod.The results show that the replacement of the conventional Q390 steel with the 800MPa super strength alloy steel D562 can not only meet the actual needs but also reduce the weight of the arm frame by about 30%,and the axial compression deformation of the rear arm of high strength steel is increased.The maximum value of the horizontal displacement of the rated load condition is increased by 4.1%.Finally,the finite element modal analysis model of the crane arm is established by using the finite element modal theory analysis theory,and the vibration frequency of the arm frame system and the rigidity of the overall structure of the arm frame are analyzed.This study provides a theoretical basis for reasonable selection of steel and design truss structure,exploring the mechanical characteristics and related design rules of cantilever crane,improving bearing capacity and reducing weight of cantilever crane.