The Structure Analysis And Welding Process Research On Large Sliding Mill

Since 1893 ball mill has been widely used in mining, building materials, chemical, metallurgical, power and smashed the raw material industry. It has played a significant role in the flour mills system. Especially in the cement flour mills operating, there is no alternative other equipment. As a widespread and very important manufacturing machine, ball mill increasingly to automation, large-scale and complicated development direction. The mills which are developed and designed to increase production mainly are sliding mills. The production of sliding mill makes the structure of ball mill more reliable, simple and become large-scale mill in the best way.With the development of production technology and widely application of sliding mill, the study of sliding mill also appeared a lot of research directions and has made great progress in the research results. They were fully applied to production practices and have a significant economic and social benefit, greatly improving the mills large-scale and scientific process.The sliding mill's main work part is its body,the main working stress include the gravity of the sliding mill and grinding balls, the impact force from grinding balls and materials to the body.So, it's very necessary to anlysis the structure security.On the other hand, because the body is consists of several parts which connect each other by welding after being rolled,the sliding mill is a good-sized welded construction,the welding residual stress will influence the intensity.In order to ensure the mill's normal work, it can adjust welding procedure and parameters to master the welding quality by researching stress intensity and distribution rule.The force of sliding mill is very complex because of the working stress and welding residual stress,so it's very necessary to use more advanced research techniques to found a universal method to judge the sliding mill's security.On the base of the summarization of other people's work, this dissertation uses numerical analysis method to analyze the stress and distortion of the important places such as shell, sliping,bearing shoes and manholes to judge the sliding mill's safety of structure. This dissertation also analyze the temperature and stress field on butt joint experimental weldment. By comparing the analysis results with calculated value or spot test value, the analysis approaches from this dissertation is proved to be feasible.The main works are as follows:(1) Analyzing the force ofφ4.6×15.5m sliding mill,including stress distribution on the shell,contact stress between the sliping and bearing shoes,finding the biggest equivalent effective stress and happening part,it's proved to meet the strength requirement after safety check;(2) Analyzing the fatigue stress of three manholes in 12 hours manhole moments of position under different working conditions, finding their biggest stress amplitude, it's proved to meet the fatigue value requirement after safety check on AISC standard;(3)According thermoanalysis to simulate the temperature field of three-dimensional finite element numerical value of the experiment model,the analysis approaches is proved to be correct after comparing the analysis results with calculated value;(4)After obtaining transient state temperature field, then carry on the finite element analysis and research to the welding heat stress field. The distribution rule of the residual stress in the butt weld joint is obtained by such method;(5)Testing the residual stress in the experimental weldment,comparing with the finite element simulation value,then verify that the analysis method of this distribution is feasible.