Patent ID: 7069957

Claim:
Heat insulation device for at least one sub-marine pipe comprising: a heat insulation covering surrounding said pipe(s), said covering being covered with a sealed protective envelope, and said envelope having a tubular shape and a longitudinal axis of symmetry, said insulation covering including a material subject to migration and said envelope being constituted by a flexible or semi-rigid material able to remain in contact with the external surface of said insulation covering when the latter warps, said device having: at least two sealed transversal partitions, each of said partitions being constituted by a closed rigid structure traversed by said pipe(s) and integral with the latter and integral at its periphery with said envelope, and at least one centralizing jig placed between said two successive sealed partitions along said longitudinal axis, said centralizing jig being constituted by a rigid piece integral with said pipe(s) and having a shape permitting a limited radial movement of said envelope on contraction and on expansion with regard to said centralizing jig, said rigid piece of said centralizing jig having an external cylindrical surface in which the perimeter of the cross section stands back with respect to that of said sealed partition and limits the warpings of said envelope by a direct mechanical stop on at least two opposing points of the perimeter of the cross section of said envelope.