| As aerospace,chemical industry,automobile and mould industry development,large-scale injection mold is widely used in various fields.Practical engineering applications,the injection molding process often exist on the surface of concave,shape deformation and defects such as weld mark,injection molded parts to ensure quality.Filling,pressure maintaining and cooling in injection molding process is in three stages: frequent problems in injection molding process,it is closely related to design,must consider the mold and injection molding process.As the prototype,this paper takes a vehicle front bumper ontology based on UG 3 d design software and Mold flow Mold flow analysis software,bumper mould for the design and testing of optimization.First,completed the bumper in the injection mold parting structure 3 d design.Bumper size is 1581 * 547 * 341 mm,black parts,using horizontal injection molding machine.To bumper injection molds,designed a car bumper injection mold structure,the main implementation of complex side parting and side core-pulling mechanism,gating system design,hot runner,overall structure,dynamic modulus and the clamping mechanism,and demoulding mechanism design and cooling system,the design of the mold parting surface and core,at the same time provide the bumper injection mold structure drawing and assembly drawing.Using UG software to complete the inner cavity parting parting surface design,core,pouring system,ejection system,side core-pulling system,cooling system,such as modeling,based on the core cavity model of 3 d data,can write the nc machining program,directly to nc machining.Second,the mold flow analysis was carried out on the bumper injection mold and injection molding process optimization.Based on Mold Flow software,using triangular mesh surface meshing,material selection and the actual use of modification of polypropylene approximate professional bumper CO 0849 PP material,complete Flow analysis,buckling analysis and the analysis of cooling.In view of the multipoint into water pouring system,contrast analyzed 8 PM and 10 needle valve type order into the plan,focus on analysis of pouring the pressure in the cavity,clamping force,etc.,the results show that the 10 points into the water when the pressure in the cavity is smaller,the maximum satisfy the requirement of the chosen injection molding machine clamping force,is more reasonable.5 journey injection molding process are discussed,and obtained the pressure curve.Third,based on the above mold structure design and mold flow analysis,work out bumper mould,and the injection molding machine process debugging and test verification.Test results show that the bumper within the product classification,injection has no obvious appearance shrink mark,weld mark,warping deformation,bubble,block printing,cold material,etc.,in line with the product performance specifications,product size to meet the fixture and loading requirements.For logo installation place slightly obviously three weld mark,put forward the improvement method of the choke is to open a arc wall on the back of the product,to produce weld line,in the arc wall and install logo will weld line keep out;In the middle of the front bumper buckling deformation phenomenon,by improving the bumper assembly card buckle to adjust,to compensate the warping deformation.The analysis of the auto front bumper design and test show that based on Mold Flow Mold Flow analysis technology,to optimize the mould structure and injection molding process,effectively solve the large stamping shape Mold production cycle is long,welding scar,mould more,air-pocket number and gate selection problems such as unreasonable. |
