Epoxy powder plus cementatious membrane for North Sea pipeline coating

Ten years ago the most favoured pipeline coating system was one based on hot tar enamels and bitumens, then more latterly a dual‐component system such as a thermosetting polyurethane tar, which retained the good adhesion of the straight tar enamels but with improved abrasion resistance and a tough and smooth finish. Polyethylenes were tried in a number of cases and although they gave greater mechanical resistance properties than coal tars and bitumens, which in turn meant that a coating of around 2mm, as opposed to 4 and 6mm, could be used, these polyethylenes lacked adhesion. So much so that an adhesive primer had to be used.