Machining Deformation Of Marine Diesel Engine Piston Skirt Research And Process Optimization

The piston is the "heart" of the diesel engine.It is the key component of the diesel engine's transmission power and movement,and the piston skirt plays the direction of the piston movement and the lateral pressure in the working process of the piston.The machining accuracy of the piston skirt will directly affect the working efficiency of the diesel engine and the life of the piston.The existing piston processing technology is immature,the piston skirt deformation is serious,and the qualification rate is low.The quality of piston skirt seriously restricts the development of diesel engine.In this paper,the key working procedure of piston machining is studied through the theory of finite element analysis and experimental verification.The improvement of ?lamping fixture and the optimization of the cutting parameters are put forward,and the machining deformation of piston skirt is effectively reduced.The main research work of this paper is as follows:(1)according to the basic theory of piston processing technology,the basic theory of mechanical manufacturing technology and the experience of processing deformation,the key process of piston skirt processing deformation is established.(2)according to the clamping constraint theory,the finite element software is used to analyze the law of the clamping deformation of the piston skirt in the key processing procedure of the piston with the clamping force and the clamping mode,and the clamping experiment has been carried out to verify the scientificalness of the finite element model of the piston clamping.(3)based on the basic cutting principle,the finite element model of piston cutting is established by using Ansys software.The influence of the cutting parameters and the radius of the cutter tip on the machining deformation of the piston skirt is studied.At the same time,the coupling finite element model of the piston clamping cutting is set up,and the effect of the clamping and cutting on the piston's deformation is analyzed.The key process of piston is optimized.(4)based on the improvement of the original fixture of the piston fine line process,the special clamping fixture is designed to solve the problem of the clamping deformation caused by the uneven height of the piston skirt.(5)orthogonal experiment is designed based on the orthogonal experiment theory.Based on the orthogonal experimental results,the mean analysis of the piston skirt deformation is analyzed and the extreme difference evaluation of the piston skirt deformation is carried out.The optimum parameters of the piston milling R341 process are obtained.