| 摘要 |
<p>A resin-lined steel pipe, characterized in that it has an adhesive layer on the inner surface of the steel pipe and, provided on the inside the adhesive layer, a plastic layer, it exhibits an initial shear adhesion of 2.0 MPa or more between the steel pipe and the plastic layer, and the inner surface of the steel pipe is in advance subjected to an undercoat treatment wherein a chemical treatment film formed by using a phosphate is subjected to a grain fining treatment, and preferably an epoxy primer layer is provided between the steel pipe and the adhesive layer. A method for producing the resin-lined steel pipe which comprises inserting a plastic pipe having an adhesive layer on the outer surface thereof into a steel pipe having been subjected to the above undercoat treatment, the plastic pipe having an outer diameter less than the inner diameter of the steel pipe, narrowing the outer diameter of the steel pipe, to bring the plastic pipe to intimate contact with the steel pipe, and then heating them at a temperature of the temperature for completion of the melting of the adhesive layer or higher and lower than the temperature for the beginning of melting of the plastic pipe.</p> |
