Abstract: One embodiment of an invention providing am inprovement upon a U-bolt bender is disclosed. The bender has a clamp for clamping a workpiece thereto and a slide for advancing the workpiece along a path. The improvement comprises a die and rollers for urging an intermediate portion of the workpiece against a forward surface of the die and for urging end portion of the workpiece respectively against sides of the die adjacent to the forward surface. The bender carries the rollers and the slide carries the die and brings the workpiece into engagement with the rollers by advancing the workpiece along the path. The sides of the die converge together and extend away from the forward surface such that as the slide brings the workpiece into engagement with the roller, the rollers urge the intermediate portion of the workpiece against the forward surface and urge the end portions of the workpiece respectively against the sides of the die, the slide meanwhile causing the clamp to clamp the workpiece to the die.

Abstract: A tube shaping machine includes a plurality of dies each having a substantially continuous, unbroken working surface. These dies are mounted with the working surfaces positioned one adjacent to the next so as to form a tube-receiving aperture therethrough, which aperture defines in cross-section regular polygon. The dies are substantially identical in configuration, this configuration being such that reciprocating each of the dies along a predetermined straight line throughout a range of positions between a fully open position and a fully closed position of the tube-receiving aperture maintains a similar regular polygonal cross-sectional shape of said tube-receiving through aperture throughout said range of positions.