Experimental and Numerical Investigation of Rubber Extrusion Forming for Multi Material Automobile Weather Strip
Rubber extrusion process is the most complex and important problem in the production of automobile weather strips. To achieve a specified geometry for an extrudate profile, together with a minimum degree of pressure loss, flow balancing of die is required. To attain this objective, the flow characteristics in die channel must be accurately described, and this demands a computational code able to predict complex 3D flow patterns. In this paper, experimental data and tree-dimensional finite volume simulations of the melted rubber flow in die region, during extrusion forming process are presented. For melted rubber flow modeling, the conservation equations of mass, momentum, and energy are solved using a 3D computational code based on the finite volume method. The shear viscosity of the melted rubber flow is described by the power-law and Arrhenius-law models, and the governing equations parameters are interpolated by the least-square fitting of experimental values that gained by Rubber Process Analyzer (RPA). The flow in one of two dies, called plate die, is found to be highly unbalanced. In the second die, by using a feeder plate, the flow at the exit of the die was properly balanced. Experimental results show that for a die with balanced flow rate, extruded profile closely matches the designed profile. Also, reveal that in low-velocity regions of die exit, the profile section tend to contraction.
Ahmad Kamal Ariffin, Shahrum Abdullah, Aidy Ali, Andanastuti Muchtar, Mariyam Jameelah Ghazali and Zainuddin Sajuri
S. M. Javadi et al., "Experimental and Numerical Investigation of Rubber Extrusion Forming for Multi Material Automobile Weather Strip", Key Engineering Materials, Vols. 462-463, pp. 831-836, 2011