摘要 |
<p>A pipe detail intended for assembly into an underwater oil or gas transport line, has a metal inner tube, with around its outer surface and over almost the whole of its length a concrete mantle. this is formed from one or more good quality hollow cylindrical lengths and a hardened filling is introduced between the mantle and the pipe, which is of ample size to permit the flow. The pipe has a dia. of 0.5-1.5 m and is given a protective coating of polyvinylbutyral. Between the neighbouring segments of the mantle sealing rings of rubber or a synthetic material are fitted. The pipe sections can be produced under the very cold conditions prevailing at sea. Cylindrical metal pipe setions can be used which are fully protected against corrosion in a manner which does not pollute he environment and is safe for the personnel. The pipe sections can be conveniently manufactured immediately before loading on to the ship and are subjected to the min. loading tending to tear off the concrete mantle in places whilst they are being laid.</p> |