Patent ID: 6455118
Filing Date: 2002-09-24
Classification: F16L,Y10T

Abstract:
A reinforced flexible pipeline for conveying a petroleum effluent at pressure greater than 300 bar, the pipeline comprising a polymer sheath, and an unbonded layer of metallic reinforcing wires wound around the polymer sheath, wherein, in the layer of metallic reinforcing wires, there are jointing spaces between the metallic reinforcing wires, and wherein the polymer sheath has an internal surface which is in contact with an effluent and an external surface which is in contact with the metallic reinforcing wires when under pressure, wherein said sheath includes(1) an internal layer of a non-externally-plasticized thermoplastic polymer or copolymer selected from the group consisting of (a) a homopolymer of an alpha olefin or a copolymer of alpha olefins, (b) a polymer of vinylidene fluoride or a copolymer of vinylidene fluoride (CF2&boxH;CH2) and at least one monomer of the formula CF2&boxH;CFX, wherein X is F, Cl, Br, CF3, C2F5, C3F7, C4F9 or C5F1, (c) a copolymer of tetrafluoroethylene with monomers of the formula CF2&boxH;CFâ€”Oâ€”R, wherein R is CF3, C2F5, C3F7, C4F9 or C5F11, (d) a copolymer of ethylene with tetrafluoroethylene(TFE) and chlorotrifluoroethylene (CTFE), and (e) a polyketone, and (2) an external layer of a thermoplastic polymer or copolymer having mechanical characteristics such that the external layer is able to withstand creep in the jointing spaces between the metallic reinforcing wires, the mechanical characteristics being defined as a shear modulus in excess of 30 MPa at temperatures of less than about 140Â° C. and a shear modulus of less than 1000 at temperatures greater than âˆ’20Â° C.