Explosively formed automobile wheel rim - uses die formed by inner and outer rings with annular explosion chamber

摘要

The rims of automobile wheels are mfd. by explosive forming. A steel strip is bent to a cylinder and the ends welded together. The cylinder is then placed in a die consisting of an inner pair of rings and an outer pair. The cross-section of the inner pair has the form of the required cross-section of the wheel rim. The outer pair are profiled to form an annular chamber around the sheet metal cylinder. This chamber is filled with a suitable explosive or fuel which is ignited and the explosion forces the metal against the inner rings to achieve the required form.