Research On Strength And Reliability Of Key Parts Of A Certain Type Of High Pressure Valve

In power station,oil transportation and industrial fluid production and transportation,high pressure valves are important fluid control components.Because of their long-term working conditions of high temperature and high pressure,their structural strength and reliability are very important for equipment safety and normal production.Safeguards.Once the valve fails,it will cause extremely serious economic losses and personal injury.However,in the analysis of high-pressure valves,the coupling of the two fields in the thermal field and the compressive stress field is often neglected,and the reliability analysis is relatively shallow.In this paper,a ultra-supercritical hard seal composite valve is taken as the research object,and the optimization design is based on the lack of reliability of the original hoist.In order to realize its reliability and the critical influence of its reliability,the numerical analysis of the two-field coupling strength under thermal stress and compressive stress is carried out and the structure is optimized.Then the reliability of the optimized structure is studied.Strength reliability analysis was performed on the collision of the key valve seat and the cone valve.The specific research contents are as follows:The reliability of the ultra-supercritical hard seal composite valve on the opening and closing device is insufficient.Based on the original structure,this paper optimizes the design of a valve mechanism combining the screw mechanism with the Maltese wheel mechanism.The original structure was compared and analyzed,and finally the valve mechanism combining the screw mechanism with the Maltese wheel mechanism was selected.The Solidworks software was used to build a 3D model of the high-pressure valve body,which was loaded into the ANSYS Workbench finite element analysis software for thermal coupling analysis.The distribution of the temperature field and the equivalent stress value under the thermal stress were obtained.The weak link of the maximum stress effect is optimized by the Design Explorer structural design module to make the overall stress more reasonable to improve the structural safety,reduce the manufacturing materials and reduce the cost.Based on the reliability calculation and analysis of the stress-strength model,the strength and reliability of the valve body are analyzed and calculated,which makes the reliability analysis result more accurate.According to the results obtained by the thermo-stress coupling analysis,based on the S-N curve of the material,based on the nominal stress method,the fatigue reliability analysis of the valve body of the optimized high temperature and high pressure valve is carried out,and the fatigue life and the valve body are predicted.The dangerous part of the fatigue damage is evaluated,and the safety of the valve body of the high temperature and high pressure valve is evaluated,and it is determined that the valve body is reliable under the working condition and meets the design requirements.In addition,the 3D modeling of the cone valve and the valve seat is carried out respectively,and the collision between the cone valve and the valve seat when the valve is closed is analyzed.In order to make the result more accurate,the elastic-rigid collision analysis and the elastic-elastic collision are introduced.Joint solution method for contact.The relationship between the maximum stress generated by the collision of the valve and the valve seat at different closing speeds is analyzed.Through the work done in this paper,not only some problems of high pressure valves are solved,but also the design and reliability research of high temperature and high pressure valves are provided.