Abstract: An apparatus and method for fixedly positioning a rotationally symmetrical constructional part having an irregular longitudinal peripheral wall consisting of a plurality of spirally wound juxtaposed tubes. The apparatus comprises a rotatable core having a peripheral surface corresponding to the inner contour of the peripheral wall for supporting the tubes with means for rotating the core about the axis of symmetry. Clamping devices are included for fixedly positioning the ends of the tubes on the core. A wire wrapping device is positioned alongside the core for applying a removable temporary wire wrapping of non-circular wire cross-section under tensile stress to the surface of the tubes.

Abstract: The constructional parts have walls formed of elongated elements, such as res or tubes, wound spirally in juxtaposition about the axis of symmetry of the part and connected to each other. The elongated elements are bent to shape utilizing a bending device having at least one bending groove conformable to the predetermined three-dimensional geometry of the part to be manufactured. One end of each wire or tube is fixed to the bending device and the other end is engaged in a clamping and adjusting device designed as a combined Cardan swivel joint which, during the bending, it utilized to continuously control the adjustment parameters of the wire or tube, about three mutually intersecting axes, in conformity with such predetermined three-dimensional geometry of the part.