Patent ID: 6922882
Filing Date: 2005-08-02
Classification: B21D,Y10T

Abstract:
1. A method of joining tubular members to form a lap joint therebetween, said method comprising the steps of: providing an internal tubular member having a first end; providing an external tubular member having an expanded region at one end thereof; forming an annular and discontinuous groove in the first end of the internal tubular member and in the expanded region of the external tubular member; heating or cooling either one of die internal tubular member and the external tubular member; joining the internal tubular member and external tubular member together by positioning the first end of the internal tubular member inside the expanded region end of the external tubular member to form an overlap region of a joined tubular member; rotationally aligning the tubular members by meshing the discontinuous grooves in the ends of the tubular members; positioning the joined tubular member between open die halves mating with one another to define a tubular cavity portion; progressively closing the die halves to progressively deform the joined tabular member within the tubular cavity portion; applying hydraulic pressure to expend and conform the joined tubular member to the tubular cavity portion; separating the die halves; and removing the expanded joined tubular member from the die halves.