Finite Element Analysis Of Surfacing Welding For High Pressure Roller Mill

As a new kind of grinding equipment, High pressure roller mill has higher efficient,moreenergy-saving and lower noise compared to conventional grinding equipment. However, theextremely poor working conditions of the high-pressure roller mill cause the roll surface badly worn.The most effective protective measures of the roll surface is grinding roller surfacing wear layer atpresent. In order to select and design better welding materials, understand the grinding roller in workstress distribution, the paper studys the work stress, welding process and the coupled force of workstress and surfacing stress of the high pressure roller mill by finite element simulation analysis.Based on the compression of materials-the rebound characteristics as well as the mechanism ofhigh pressure roller mill work, the material conditions and movement regularity are analyzed and thework stress model of high pressure roller mill grinding rollers is figured out. Aiming at the rollgrinding working characteristics,the paper has established finite element model for working stressanalysis and achieved the loading of the service load with force subroutine. The simulation resultsshow that, the maximum radial stress in the process of high pressure roller mill grinding is199.3MPa,which locates at15mm below the surface of the grinding rollers. Axial stress is maximumin the central part of roll grinding, and gradually reduced to the both sides.In the middle of thegrinding rollers, with central angle α=0, maximum, to137.8MPa.According to the grinding roller surfacing the actual situation, the paper has established1/4ofthe grinding rollers as finite element model, and has studied the temperature fields and stress fields offinite element simulation analysis. By selecting appropriate heat source model, the materialparameters, the model parameters, more accurate results of the temperature field are obtained. Basedon the temperature field, the distribution of the stress field in the welding process is studied. Theresults show that in the radial direction, the surface weld zone showed compressive stress, heataffected zone showed tensile stress, radial stress reaches a maximum at20mm below the surface ofthe grinding rollers. A comprehensive analysis of the stress distribution in the roll grinding work,work stress and surfacing stress coupled analysis results show that the coupled stress in the radialdirection in less than18mm at the surface of the grinding reachs a maximum value of536MPa stress,surface stress reachs130MPa. Through the stress analysis, good ductility and toughness surfacingmaterial with more than536MPa yield strength greater should be chosen.To carry out the simulation of the multi-layer multi-pass welding of the roller, the paper has optimized the welding sequence, the head to head (H-H) and the head-to-end (H-E) welding processwere analyzed and compared. The results show that thehead-to-end (H-E) welding sequence reduceswelding residual stress, but coupling stress distribution was little affected.In this paper, the work stress of high-pressure roller mill, surfacing process and coupling stressare analyed by finite element simulation, the various stress distribution of the roll grinding are studied.The results will guide the surfacing process of formulation and the choice of welding consumablesand set a theoretical foundation for the surfacing process of finite element analysis.