Effects Of Temperature On Parts' Wall Thickness Homogeneity In Extrusion Blow Molding

Extrusion blow molding are widely used in the molding of various hollow containers and many complex parts, because of its characteristics such as lower production cost , more superior in forming performance, stronger in adaptability and higher integrity in formed parts. However, with the Structure of industry parts becoming more and more complicated, and blow ratio not uniform seriously, the problem of wall thickness not uniformity, has become the biggest bottleneck that restrict the development of extrusion blow molding.This paper took an oil tank company as the research object, analyzed the main technologcial conditions that affecting its wall thickness distribution, weight and the surface weight, and proposed an optimization scheme for partly enforced cooling of extruded parison and wall thickness distribution.Analyze the process of extrusion blow molding, and make sure that the main reason for lacking of wall thickness uniformity is different in blowing ratio of each section, according to tank's structure. Also, design, elaborate blow molding and carry out experiment research , and what's more, talk about the effects of some blow molding technologcial conditions, such as different temperature of handpiece, rotation speed of screw, temperature of mold blow stress, to wall thickness distribution, weight and surface weight of tank parts. Choose cooling waters or cold air to cool extruded parison of most part of the blow compulsively, and let the temperature decrease sharply. Then, before the mold closing, temperature gradient of extruded parison was formed. The result came out with improved wall thickness distribution of tank parts in extrusion blow molding, and it demonstrate that the method of partly enforced cooling of extruded parison to optimize wall thickness distribution was possible. Through orthogonal experimental,analyze the influence significance of each factor to wall thickness distribution of tank., and choose the best level of each factor, and then, decide the best blow molding technologcial conditions. Through the method of partly enforced cooling of extruded parison to optimize technologcial conditions of blow molding tank parts can improve its wall thickness distribution apparently. At the same time, raw materials can be saved, and the cost saved. Its application and generalization perspective shows extensive, and it is good for pushing the application of Extrusion blow molding in complicated industry parts. So, it possesses great economic importance.