METHOD AND PLANT FOR MANUFACTURING LENGTHS OF PRE-INSULATED PIPES

摘要

Method and plant for manufacturing a length of pre-insulated pipe according to the mix-pull technique (MZT) and comprising at least one service pipe (2) with a surrounding protective casing (5) and an intermediary layer of insulating foam material wherein foaming of the insulating foam material (17) is carried out in the space (10) between the at least one pipe (2) and the surrounding casing (5) concurrently with the mixer head (3) being moved in axial direction relative to the pipe (2) away from the closure member (6) with such a speed during the foaming process that the foam (17) will cure continuously, thereby providing a second support (B) for the pipe (2) in essentially a constant distance (C) from the mixer head and preventing the preinsulated pipe from bending.