Study On Friction And Wear Mechanism And End Face Performance Of Dry Friction Mechanical Seals

Because of its special working conditions,dry friction mechanical seals often face unstable performance and seal failure in practical work.Improving the performance of dry friction mechanical seals has always been the most important part of dry friction mechanical seals research.The purpose of this paper is to establish a numerical analysis model for dry friction mechanical seals and to explore the friction and wear mechanism of dry friction mechanical seals with different material pairs.According to the actual working state of the seal,the thermal-structural numerical simulation model of dry friction mechanical seal is established,the boundary conditions of the thermal-structural numerical simulation model are determined,and the numerical simulation results under different working conditions are analyzed and compared.The analysis results show that the peak temperature between the end faces is higher and the deformation of the end faces is larger under high parameters.Based on the fractal theory,the fractal parameters of the seal face are determined,the actual micro-morphology and contact characteristics of the seal face are explored,and the numerical calculation model for the performance of the dry friction mechanical seal face is established.Comparing the numerical results under different fractal parameters,the range of fractal parameters of actual seal face is determined,which provides theoretical guidance for the processing of seal face in practical work.Based on the end-face model of dry friction mechanical seals,four performance parameters,peak temperature,friction power consumption,wear rate and leakage rate,are comprehensively analyzed in this paper.According to the analysis results,it is defined as the comprehensive performance of the end-face.The influence of different parameters on the comprehensive performance of dry friction mechanical seals was analyzed,and the optimum structural parameters for dry friction mechanical seals were determined:the width of end face was 2.3-2.7 mm,and the load coefficient was 0.6-0.7.The physical parameters suitable for dry friction mechanical seals are determined,which provides theoretical support for material selection of dry friction mechanical seals.By using the method of orthogonal analysis,the specific parameters suitable for the design conditions in this paper are obtained.According to the optimum parameter range,several typical sealing materials were selected for matching.The friction coefficient in the friction process and the morphology of the end face before and after the test were measured by the test method.The friction and wear mechanism of different material pairing under different working conditions was explored according to the measurement results.It is concluded that the friction and wear mechanism of different material pairing is different.By analyzing the friction and wear mechanism of different material pairing,the change of seal face morphology and steady state morphology can be predicted to a certain extent,and the accuracy of numerical calculation results can be improved.A dry friction mechanical seal test device was designed and installed.The comprehensive performance of the seal face under different working conditions was analyzed.The experimental results and numerical results were compared to verify the reliability of the numerical results.In this paper,the end face model of dry friction mechanical seal is established to provide theoretical support for the design of dry friction mechanical seal.By analyzing the end performance and friction and wear mechanism of different material pairing,a new idea is provided for the study of sealing end performance,which can guide the selection of dry friction mechanical seal material under different working conditions.