IMPROVEMENTS IN OR RELATING TO BI-METAL LINED PIPE

摘要

A bi-metal lined pipe and methods of forming such a pipe suitable for spooling onto a reel for marine pipelaying applications, the pipe comprising a carbon steel outer pipe and a liner of corrosion resistant metal, in which the liner is secured along its length to the inner surface of the outer pipe by circumferential fixing means having a circumferential shear strength greater than the circumferential shear stress which would be induced by bending the pipe to a predetermined minimum radius of curvature. The circumferential fixing means securing the liner to the outer pipe includes at least one of the following: adhesive agents selected to provide a circumferential shear strength greater than the circumferential shear stress which will be induced by bending a given combination of outer pipe and liner to a predetermined minimum radius; soldering, brazing or other similar technique to produce a mechanically acceptable bond between the liner and the outer pipe without fusing the bulk material; mechanical interlocking of the liner and outer pipe; solid-phase welding, such as electrical resistance spot welding from the interior of the liner. The circumferential fixing means may be used in combination with known friction-bonding techniques.