The Research Of The Sliding Slewing Bearing Contact Force Balance Of The Super Large Lifting Equipment

Today, in order to meet the needs of the development of marine resources, large hoisting equipment demand surge. The lifting capacity is increasing higher:the hoisting tonnage and arm increase. Slewing bearing is one of the key parts of the rotary lifting equipment, and ensure the key of the heavy equipment hoisting work stability, security. Structure of slewing ring affect the lifting other parts of the device structure, and determines the lifting capacity. Based on the analysis of the trolley and the jacketed roller slewing bearing structure form, sliding type slewing bearing has been proposed. Sliding type slewing bearing has the advantages of more compact structure, lower center of gravity, more strong stability, larger bearing area, higher strength. The structure is divided into the support structure and the rotary body structure. Because the rotary body structure stiffness is weak, the significant defect in terms of the lower rotary structure is that the slewing bearing’s pressure of the sliding surface is non-uniform in the working state. With the situation of the non-uniform, the large bearing force area gets very heavy wear and tear, and affects the stability, the rotation of the security and slewing bearing service life.Taking the sliding slewing bearing of a super-size marine crane as the research object, basing on the finite element contact theory, applying the finite element analysis software ANSYS, a group of finite element models have been established. Through the comparative analysis of multiple sets of model results, distribution of bearing loads of the chute has been researched, to solve the problem of uneven distribution of bearing pressure of the sliding slewing bearing, and then guide the design of slewing bearing.The problem of contact between the chute and the fixed orbit of the sliding slewing bearing has been discussed, determined the method solving contact problem between the chute and the fixed orbit. Analyzing the slewing bearing structure, finite element model of slewing bearing has been constructed more reasonably by using the finite element analysis software ANSYS.The impact of the upper support structure and the lower rotary local structure of the slewing bearing on the evenness of bearing pressure is studied. By enumeration,3kinds of designs with the different arrangement of the support columns,2kinds of designs with different ribs arrangements and5kinds of designs different chute extended area are listed. By referencing the calculation results of4limit load conditions, the impact result of the support columns of the slewing bearing on the evenness of bearing pressure is got by comparative analysis. The research indicates that the most beneficial supporting position of the front outer support columns for even distribution of bearing pressure is to the front-end outer support columns as much as possible close to the front end, and the most beneficial rotary structure for balanced distribution of bearing pressure is that the intermediate rib below the inner support column has been arranged transversely, and the transverse rib has been increased between the ribs below the inner and outer lateral support column; the orbit beam has been extended to between15°to20°.The confirmatory test has been designed based on the above research. The design of the test model is that the support column position toward the front end, the orbit beam with transverse stiffening rib and the orbit beam with the20°end expansion. Do the loading test to verify the accuracy of the calculation of the finite element design model.