Warpage Analysis And Optimization Research On Plastic Parts Of Upper And Lower Handle Plastic Parts Of Meat Clipper

In injection moulding,warpage is one of the common defects of thin shell injection moulding parts.When the warping deformation exceeds the allowable error,it will affect the appearance and assembly of plastic parts,and large warping deformation should be avoided as far as possible.In the actual production process of injection moulding,due to the influence of various complex factors,it is often difficult for die designers to predict the possible defects of injection moulding parts.It is necessary to repair and test several times before qualified injection moulds can be obtained,which obviously can not meet the requirements of agile manufacturing.Computer aided engineering(CAE)technology can simulate the injection molding process of injection parts and predict the defects of injection parts in advance.It has far-reaching engineering significance for reducing the number of mould repair,improving the quality of mould,shortening the development cycle and saving production costs.This paper takes the upper and lower handle plastic parts of a meat gripper developed by an electrical appliance company as the research object,aiming at the defects of warping deformation of the upper and lower handle plastic parts of the meat gripper,according to the relevant technical requirements,under the principle of economic reasonableness and technical feasibility,using CAE technology to analyze the causes of warping deformation of the plastic parts and its main influencing factors,in order to find out how to reduce or eliminate the warping deformation of the plastic parts.Optimize the scheme to solve the appearance and assembly of the upper and lower handle plastic parts of the meat gripper.Aiming at this goal,the main research contents and results of this subject are as follows:1.This paper summarizes the previous studies on warpage deformation in injection moulding,the existing methods for optimizing warpage deformation and the latest research progress in this field,studies the formation mechanism and main influencing factors of warpage deformation,analyses and derives the mathematical model of warpage and its relationship with residual stress,and puts forward some suggestions for reducing or eliminating it from the aspects of moulding technology,moulding materials and die design.Method of warping deformation.2.The plastic part model was pre-processed by UG software and imported into Moldflow Insight software.The filling,holding,cooling and warping of the pouring system and cooling system were analyzed according to the original die structure scheme of the upper and lower handle of the meat gripper.The warping deformation of the original die structure scheme was found.The numerical simulation results were consistent with the actual test results.Then according to the simulation results of CAE,the causes and main influencing factors of warping deformation of the upper and lower handle plastic parts of meat gripper are analyzed,which provides the basis for the analysis of the next optimization scheme.3.According to the results of die flow analysis,the warping deformation of the upper and lower handles of meat gripper was optimized from two aspects: optimizing process parameters and using low warping materials without changing the die structure.From the analysis results,these optimization schemes improved the warpage deformation of plastic parts to a certain extent,but the optimization results failed to meet the target value of warpage control within 2mm.4.Secondly,the die structure is optimized from the gating system and cooling system respectively without changing the optimization scheme of the die structure to achieve the target value.There are two schemes to optimize the gating system: one is the sector gate for the left and right cavity of the scheme I,the other is the different gate for the left and right cavity of the scheme II.From the analysis results,the maximum warpage of scheme I is 2.952 mm,and scheme I can not meet the target value;the maximum warpage of scheme II is 1.394 mm,which can control the target value of warpage within 2 mm.The optimization of cooling system adopts conformal cooling water channel based on 3D printing technology.The analysis results show that the maximum warpage of plastic parts is 1.136 mm,and the optimal cooling water channel is the optimum scheme with the minimum warpage in the above scheme.5.Considering the production situation and manufacturing cost of the enterprise,the optimization scheme which is economical and can meet the assembly requirements is selected.The structure of the die is modified by different gate forms in the left and right cavity,and the die is tested and verified.After testing,the maximum warpage of plastic parts is 1.2 mm,which meets the tolerance requirement of warpage control within 2 mm,and finally achieves the research purpose of this topic.The research results in this paper can provide reference for the optimization of injection mold and the control of warpage defects of injection parts.