55312 ⎘
Mechanical deformation without removing material, e.g. in combination with laminating; Shaping by bending, folding, twisting, straightening, flattening or rim-rolling; Shaping by bending, folding or rim-rolling combined with joining; Apparatus therefor; Bending or folding combined with joining; Bending plates, sheets or webs at right angles to the axis of the article being formed and joining the edges for making articles of definite lentgh using internal forming surfaces, e.g. mandrels Machines therefor having additional mandrels, e.g. mounted on a turntable, or on chains