Experimental and Numerical Study of Axial-Feed Hot Gas Tube Forming of Polypropylene

Abstract

Polymeric materials have attracted a lot of attention for the past several decades. Different sectors of manufacturing industry, such as packaging, building and automotive industry have introduced polymeric materials in their applications. Common polymer manufacturing processes include thermoforming and blow molding. In this research, characteristics of a new polymer manufacturing process, referred to as axial-feed hot gas tube forming (HGTF) are studied. Experimental studies were conducted to form a simple axisymmetric component from extruded polypropylene (PP) tube by varying several key process parameters such as internal pressure, temperature and axial feed. Tube shape and deformation characteristics were studied as a function of the above process parameters. In addition, two consecutive material models have been utilized for finite element simulation of axial-feed HGTF of PP tube using a commercial FE code. One of them is conventional hyperelastic Ogden material model and another is more advanced viscoelastic-viscoplastic Augmented Hybrid material model (AHM), that has been recently developed. Simulation results from two models were analyzed and compared with the experimental results and good general agreement has been obtained. Results showed that application of more advanced AHM material model led to improved prediction of part shape and strain distribution over the part profile.