Method for the production of multi-channel tubes and a drawing die for carrying out the method

Method for the production of multi-channel tubes which consists in that a rod (2) with ribs (3) arranged radially over its entire length is introduced temporarily into a thin-walled cylindrical sleeve (1) and drawing is then carried out to fix the ends of the ribs (3) to the inner wall of the sleeve (1). Drawing is performed through a drawing die which has an angle ( alpha ) between the generator of the compression zone and the axis (b) of the drawing die of over 45 DEG . The stipulated length of the projection of the zone of the common shaping of the sleeve (1) and the ribs (3) onto the axis (b) of the drawing die is at most six times the thickness of the rib (3) of the rod (2). The drawing die comprises the following zones one behind the other: an inlet zone (20), a compression zone (21) for compressing the sleeve (1), in which the generator is at an angle (ss) of 2-20 DEG to the axis (b) of the drawing die, an additional compression zone (22) for the joint compression of the sleeve (1) and of the ribs (3) of the rod (2), in which the generator is at an angle ( alpha ) of 45-90 DEG to the axis (b) of the drawing die, a cylindrical calibrating zone (23) and an outlet zone (24).