Inventors:
Blair T. Allison - Cheswick PA
Thomas J. VanSumeren - Waterford MI
Robert P. Evert - Allison Park PA
John S. Schultz - McKeesport PA
Assignee:
Aluminum Company of America - Pittsburgh PA
International Classification:
B21D 1102
Abstract:
A process for stretch forming hollow metal bodies, such as aluminum alloy extrusions. The extrusions are stretched longitudinally, bent transversely of the pulling direction, and then subjected to pressure from an incompressible fluid in a hollow interior. In a preferred embodiment, the incompressible fluid is water at a pressure sufficient to deform at least part of the extrusion outwardly of its hollow interior. The incompressible fluid reduces dimensional distortions in the shaped product.