Method for producing a branch pipe

The invention relates to a method for producing a branch pipe. In order for the dependable production of a branch pipe with virtually any desired design of the branch to be made possible in a simple way it is proposed that an elongate, straight main curvature and at least two lateral curvatures, respectively branching off from a longitudinal side of the main curvature, lying opposite each other with respect to the central longitudinal axis of the main curvature extending in the material of the blank and having a mirror-symmetrically arranged base line are formed from a blank by deep-drawing. After the forming operations, the blank is trimmed in such a way that a vessel-like shell part, which is open in the longitudinal direction, is formed from the main curvature, and half-sleeves, which adjoin the shell part, lie in the same plane as the shell part and are open in the direction of their extent, are formed from the lateral curvatures, and that sheet metal strips serving as joining flanges extend along the outside of the lateral edges of the shell part and the half-sleeves. Subsequently, the shell part is bent about a spatial axis parallel to the central longitudinal axis until the joining flanges corresponding to one another on both sides of the shell part lie against one another, and, after that, the joining flanges are connected to one another.