Research On Several Technologies Of Cooling And Shaping System

The plastic profile has developed for decades,and has been widely applied.At present, in China.The profile has formed a large-scale production capacity,simultaneously the domestic mold manufacturing technique also has been greatly enhanced.But comparing with the situation overseas,there is still a big gap that mainly manifests in the extrusion speed and the quality of the profile.The present situation in our country is that the design of the system of cooling and stereotype of the profile extrusion die almost completely depend on the designers' experience and the simple design theory.Then the adjustment is carried out through the to make up the shortage of design,which thus often affects the efficiency of the design and producing.So the design cycle of mold is prolonged,and the production volume and quality of the profile product can not be guaranteed.In view of the above problems,the numerical solution method is introduced into the system of cooling and stereotyping of the profile extrusion die in this thesis.The thesis also makes an analysis on the strain and cooling influence on the stereotype mold of plastic profile and a more rational method to decide the length of stereotype mold through synthetically consideration of temperature and strain is given.At first,through coupled field analysis and theoretical analysis of thermodynamic,it gets to know that the heat transfer process of profile in stereotype mold is instantaneous. Through establishing geometry and ANSYS mold to make thermal analysis of the profile mold.the thesis shows the initial temperature field of the stereotype mold.the temperature field that exists when the profile leaves stereotype mold and stress field generated by the displacement of the profile wall.On this basis,the thesis simulates the contingency situations of stereotype mold in profile,analyse various reasons and the influencing factors generated by the extrusion process of the profile.Among them,time(t),wall thickness(h). heat transfer coefficient(a),side(d) are the main factors that affect the warpage amount(δ).Then.it makes fluid analysis of s-shaped waterway and straight hole watercourse ANSY molds by using ANSYS.It gets water flow speed(v),reynolds number(Re).Prand(?) number(Pr) by the material parameters of fluid and boundary conditions.judges the movement state of the water flow and determines the convective heat transfer coefficient(a). At the same time.it makes thermal analysis of the two models of profile trench site--with small holes and without small holes.Comparing in the temperature field,the profile trench site with small holes will get smaller,thus the quality of the production can be improved.At last.applying ANSYS.the thesis makes an analysis that the strain,cooling influence on the stereotype mold of plastic profile and the determination of the length of the stereotype mold are related to the extrusion speed,profile dimensions,state of the cooling systems and other factors.It also analyzes and tests the strain law of the profile roughcast after continuous and different working of stereotype mold and water tanks.The basis for the rational design of the stereotype mold reveals the homogeneous cooling's important significance in the design of the cooling system of stereotype mold.This kind of method has theoretical and practical significance in shortening the design cycle of mold.guaranteeing the homogeneous cooling of the profile,increasing the quantity and production volume of the profile,and making profile further develop towards the trends high-performance. high-speed and precision.This thesis uses the ANSYS to make a thorough analysis of the cooling and strain of the stereotype mold in profile and give a rational way of determining the length of the stereotype mold.It can reduce the time of repairing the mold,shorten the design cycle,and save the design cost.So it has promotion value and practical significance.