Patent ID: 10183320

Abstract:
A method for producing a multilayer large pipe having an outer support layer and at least one inner liner layer. Advantages with regard to productivity and the properties of the multilayer large pipe are achieved by the sequence of method steps wherein production of a support sheet is pre-bent to a predetermined initial bending radius for the support layer and at least one liner sheet is pre-bent to a predetermined initial bending radius for the liner layer, placement of the at least one pre-bent liner sheet against the inside of the pre-bent support sheet, with a positioning and parallel alignment of its longitudinal edges extending in the direction of the bending axis in order to form the support layer and the at least one liner layer, there is integral joining of at least one of two longitudinal edges of the at least one liner sheet to the support sheet, shaping of the composite of the integrally joined support layer and at least one liner layer to form a slit multilayer large pipe by a bending machine, with nonpositive, frictional engagement in liner regions that are not integrally joined, and there is closing of the remaining gap of the slit multilayer large pipe with a longitudinal seam by welding.