PIPE COATING

摘要

Steel pipe is provided with an external protective coating by first applying a corrosion protective coating of fused powdered epoxy resin adhered to the pipe, then applying (e.g. as by wrapping a sheet) an outer polyolefin layer directly onto the corrosion protective coating. The outer sheet of polyolefin is provided with a pressure-sensitive adhesive or a hot melt adhesive which adhesive may also be reactive with the epoxy coating (e.g. one having free carboxyl group such as ethylene acrylic acid copolymer). The polyolefin is preferably polyethylene or polypropylene and most preferably polyethylene. Either high or low density polyolefin may be used.