Research On Several Key Technologies Of Jib Crane

          Jib crane is a kind of jib luffing, can rotate up and down crane, by adjusting the angle of the arm frame to change the amplitude. Jib cranes can be wheeled up and down slewing cranes. The boom design of large jib crane adopts "pole" structure, which is better than that of horizontal arm tower "beam" structure, the proportion of boom structure is smaller, and the maximum weight is larger.

          The movable-arm luffing method is widely used in various types of revolving cranes, such as ocean engineering cranes, marine cranes, jib towers, etc. There are some key problems in the design of jib cranes, such as the determination of pitch spacing of truss-type jib, the determination of hinge-point coordinates of luffing mechanism, and the calculation method of lifting performance. Although there are some specific problems in the previous periodicals, but the research method is cumbersome, the aim is not to design the whole crane, and the conclusion is not well applied to the actual design, there are some limitations. In view of the above problems, this paper, from the point of view of mechanics, makes a systematic study on several key technologies existing in the design process of jib cranes, and provides reference for the design of the crane. The main research work and research results are as follows:

         (1) Sum up several realization forms of mobile counterweight, this paper finds out the changing regularity of gravity center position with the elevation of the arm frame, and takes the steel wire rope counterweight movement as an example, expounds the factors that need to be considered in the design of moving counterweight position, and provides reference for the design of mobile counterweight of the movable arm tower crane.Jib Crane

         (2) from the ideal pressure bar, the actual pressure bar, based on the strength and stability of two-way bending rod, the method of determining the spacing of single limb joints of truss-type members is deduced scientifically, and the maximum axial pressure of a given member is deduced, which provides reference for the design of truss-type jib system.

         (3) Starting from the actual force of the component, in this paper, the relation between the hinge point and the force of the variable amplitude system is deduced by the mechanical method, and a simple mathematical relation can be used to determine whether the hinge point is suitable, to avoid the programming debugging process in the usual optimization design, and to provide reference for the design of the system hinge point.Jib Crane

         (4) developed the auxiliary design system of jib crane. Its main task is the structure check and crane performance calculation of various movable jib cranes. The system is suitable for the structure design of the crane with any wire rope luffing mode, and carries on the complete analysis process according to many different design specifications. At the same time, taking the Dalian Engineering Machinery Research Institute and Changsha Zhong Lian Heavy Industry Science and Technology Development Co., Ltd. As an example, the paper verifies the correctness and feasibility of the research results and the practicability of the special software system through the finite element analysis.Jib Crane