Analytical models for the inflation of a polymeric tube

In the blow moulding processes, a tube-shaped parison (also called preform) made of polymer is inflated inside a mould in order to obtain the desired bottle shape. The free inflation of a cylindrical tube (a simplified kinema tic of inflation for the preform before contacting the mould) has been inve stigated in order to develop analytical models and then provide reliable va lidation material for finite element software. The solutions calculated for a tube made of a Newtonian fluid and a Lodge's rubberlike liquid material using both exact volumic approach and thin shell approximation have been an alysed and compared. (C) 2000 Editions scientifiques et medicales Elsevier SAS.