METHOD AND EQUIPMENT TO MANUFACTURE MULTILAYERED TUBE THAT CONSISTS OF THERMOPLASTICS, ESPECIALLY POLYOLEFIN

摘要

PROBLEM TO BE SOLVED: To produce a multilayered pipe comprising a thermoplastic material, particularly polyolefin hard to receive influence with respect to the outer diameter tolerance of a pipe to be covered with a tube. SOLUTION: An extrusion molding apparatus for the extrusion molding of at least one tube in a producing direction 9 is provided. A sizing device for molding a pipe 8 with an outer contour is arranged in succession to the extrusion molding apparatus and a preheating device 19 for heating the outer surface of the outer contour to welding temp. is connected to the sizing device. Further, a co-extrusion molding head 7 equipped with an extrusion molding machine for forming a tube 46 to the periphery of the pipe 8 by co-extrusion molding is provided. The head 7 has a partial vacuum connector for welding the tube 46 to the outer surface 45 under difference pressure between circumferential pressure and a partial vacuum.