Patent ID: 7341686
Filing Date: 2008-03-11
Classification: F16L,Y10T

Abstract:
1. A method of manufacturing a reelable double-walled rigid pipe for underwater transportation of fluids, wherein the pipe comprises an inner flow pipe, the interior of which defines a passage for transporting the fluid, an outer carrier pipe which surrounds the flow pipe, and a plurality of longitudinally spaced separating elements between the inner and outer pipes which define an annular space therebetween, the method comprising: selecting dimensions and properties of the inner pipe and the carrier pipe according to an intended fluid transportation application, and an intended pipeline location, and to have suitable mechanical properties which permit the double walled pipe to be plastically deformed for reeling on a vessel reel and then straightened while being laid offshore; assembling a double walled pipe using the selected carrier and flow pipes, and the separating elements; and forming a device within the double-walled pipe for arresting longitudinal propagation of buckling of the outer carrier pipe, by: