Research On Full-process Machining Methods Of Slender Hole Parts With Interference State

Slender hole processing has always been one of the most difficult problems in the production of manufacturing enterprises,and also one of the most unstable processing procedures.In production: cutting tools,blank batches,equipment status,process operators,process methods will affect its processing quality.For a long time,technicians are constantly looking for process schemes that can ensure the stability of the processing of slender holes and minimize the influence of the above factors as far as possible.In the production and processing of a slender hole part derived from a multi-way valve,an automatic machine tool is required to stably cut the part and realize full-order processing.However,because the part not only has an elongated hole structure,but also because the elongated hole is an eccentric hole structure,the stepped rod at the axial position of the part interferes with the tool during drilling,which increases the difficulty of processing this part.After reviewing the development of deep hole machining tools and theory,and expounding the examples and methods of deep hole machining for different materials,working conditions,and tools at home and abroad,it is necessa ry to formulate a process plan consistent with its own.By comparing the existing deep-hole machining tools,a tool suitable for the working conditions of this part-gun drill was selected,and the design method and processing parameters of gun drill were discussed and calculated.The tool modeling was completed by these parameters And non-standard paper designs.In the finite element analysis of deep hole machining,the non-linear simulation method of thermal-mechanical coupling analysis by the finite element method is discussed,and the constitutive relationship,cutting separation criteria and other factors that affect the accuracy of cutting simulation are described.The literature search defines the constitutive parameters of the Y40 Mn material.The ABAQ US finite element software is used to simulate the cutting simulation of the gun drill for the Y40 Mn material.The reasonable processing parameters are analyzed and compared,and the cutting state of the gun drill bit is simulated.The cutting force is simulated after the cutting tool is used as a variable body,and the stress and strain diagrams of the tool deformation are generated.By defining the simulation and adding the prefabricated hole or the drill sleeve,the maximum deformation occurring in the middle of the tool is simulated and analyzed.The amount of displacement was found to directly affect the life of a gun drill by using a gun drill to process the deformation of the drill pipe.In the practical optimization scheme,by selecting reasonable pr ocessing equipment and allocating reasonable process allocation scheme of tool-tooling-assistant-parts relative to machine tool,this paper proposes for the first time a processing scheme of linkage cutting by using multi-turret machine tool with assistant supporting tool of tool.By utilizing the characteristics of multi-turret machine tool,tool and assistant are installed on the turret respectively.Tools,through the different control channels of the turret,compiled the program of gun drill deep hole processing with tool and auxiliary tooling linkage.The optimized scheme solved the following problems: Gun drills need to be guided and centered before drilling parts,the impact of cutting tools on machining caused by cutting force deformation,and the problem of automatic sequential processing of machine tools.Through actual installation and debugging and small batch trial production and processing verification,it is proved that the above optimization scheme has the conditions of batch production.The design of corresponding checking fixtures,the processing aperture size and positioning degree of the parts discussed are measured in batches.The measurement results of approximate positioning degree was analyzed by the process capability index(CPK)of the quality tool,and the small batch processing quality of the parts is measured.The results show that the quality is good.Furthermore,the quality stability of the proposed scheme for the optimization of the machining of slender holes with interference st ructure is verified.