INRICHTING VOOR HET AANBRENGEN VAN EEN LANGSLASNAAD IN EEN TOT BUIS GEBOGEN BAANVORMIG KUNSTSTOFMATERIAAL.

摘要

Forming a lateral longitudinal joint on a tubular body formed from a strip of laminated material having a layer capable of being attached near an interior layer of thermoplastic material, the lateral edges of the strip overlapping longitudinally, by heating the overlapping edges to soften the layer of thermoplastic material and bringing into a flowable condition, applying a non-uniform transverse pressure reduced in the neighbourhood of the overlapping edge, causing the thermoplastic material to flow towards the overlapping edge and covering the layer susceptible to attack. The invention includes apparatus for carrying out the process. The process enables the continuous production of internally resistant smooth laminated tubes.