Method for pressing hollow structures through internal pressure has equal thickness walls each side of the corners to prevent rolling of the corners

摘要

A method for shaping hollow profile structures, eg. light alloy tubular sections, has hydraulic pressure applied from inside the structure. the sides of the structure can have different wall thickness and to ensure that the pressure does not cause the edges to roll ie. the thinner wall to rupture, the thinner wall is joined to the corner by a thicker section, equal in thickness to the adjoining thick wall. This ensures an even forming of the structure. The thickened edge section of the thinner wall is about 12 to 20 mm and is linked to the thinner wall by a sloping step profile.