Study On Simulation Technology Of Hot Forging Plumbing Valve Body Based On CAE

Valves play an important role in the fields of economy industry and military industry.The hot forging process of brass alloy valve body has been widely used in China for less than 15 years.Many process designs were based on the application of production and the accumulation of experience.The research on hot forging technology of plumbing valve body in our country is still relatively weak,which makes most of the production enterprises cannot find a solution in time when the product is defective,and consumes a lot of manpower and material resources.The quality of the hot forging process is one of the decisive factors for the quality and efficiency of the valve body blank.Therefore,the research on critical technology of valve body hot forging is of great significance for improving valve body quality and rational design of die system.Based on the knowledge of elastic-plastic finite element theory,and aiming at the cracking failure of a ball valve body,the following research works are carried out:(1)This paper aiming at the problem of establishing friction model under brass hot forging condition summarized the application and research of friction in hot forging process and its simulation.By designing and implementing the ring upsetting experiments at different temperatures,the functional relationship between friction coefficient and temperature are obtained based on data fitting.And the corresponding friction model are established.(2)Aiming at the defect of traditional mechanical hammer forging process under actual working conditions,the numerical simulation model are established by abstracting the process parameters.This paper analyzed the design defects which cause the valve body cracking.By comparing the actual crack location with the simulation results of hot forging,the judging criteria for predicting the valve body cracking failure are concluded.(3)Aiming at the design defects of the traditional mechanical hammer forging process for the valve body,this paper proposes two sets of production process schemes,and the process parameters are abstracted,and the process characteristics are analyzed,and a numerical simulation model is established.The advantages and disadvantages of the valve bodies produced by the two schemes have been preliminarily evaluated by the application of forging process analysis and the judgment criteria.(4)In this paper,ammonia fumigation and crack development experiments of valve body are designed and implemented.Through the comparison and analysis of experimental data and simulation results,the correctness of the numerical simulation model is verified,the quality of valve body produced by hydraulic multi-directional die forging process is verified,and the rationality and practicality of the proposed criteria for judging valve body quality is further illustrated.