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 kinematic of inflation for the preform before contacting the mould) has been investigated in order to develop analytical models and then provide reliable validation material for finite element software. The solutions calculated for a tube made of a Newtonian fluid and a Lodgeʹs rubberlike liquid material using both exact volumic approach and thin shell approximation have been analysed and compared.