THREE-COAT COATING SYSTEM FOR METAL PIPES AND METHOD OF COATING THE OUTSIDE OF A METAL PIPE WITH A THREE-COAT COATING OF THIS KIND

摘要

The invention relates to three-layer metal pipe coating compositions based on a powder primer, on a thermoplastic hard adhesive and on a polyolefin cladding. The powder primer contains epoxidized novolak resins, phenolic crosslinking agents and fillers based on crystalline silicic acid modifications. The invention likewise relates to a process for the exterior coating of metal pipes by a three-layer method, in which the powder primer described is applied to the metal pipe, a thermoplastic hard adhesive is applied to the powder primer, and subsequently a polyolefin cladding is applied.