Abstract: Methods and apparatus for the processing of a continuous blown film undergoing collapsing in which a plurality of differential elements of the film follow respective streamline paths which are approximately equal in length to the path of the longest streamline thereby substantially equalizing circumferentially varying shape change induced machine direction stresses and reducing the residence time variations within higher thermal energy regions so as to significantly minimize the commonly rather large magnitudes of variations of gauge, energy to break and machine direction lengths of the solidified material. The method and apparatus provide the potential to structure more uniformly the macromolecular arrangements existing within the material and allow the blown film extrusion of higher modulus materials than have heretofore been possible.