Patent attributes
Method of a spin forming conical fittings for HVAC systems from 10 to 26-gauge steel material. A flat pattern is cut, stamped or otherwise formed from flat sheet stock or roll stock. The pattern is rolled or otherwise formed into a frustoconical shape. The workpiece is engaged with a die, and the end portions of the workpiece are formed as the workpiece is spun to press the workpiece against the die. In this manner, a small diameter collar portion is formed at the smaller end of the conical connector and/or a larger diameter collar portion is formed at the larger diameter end of the conical connector. Also, a flange connector can be formed at the larger and/or smaller end portions of the conical connector using spin forming or a combination of spin forming and roll forming techniques.
