An unbonded flexible pipe

Patent metadata

Field	Value
Publication number	US-2016003382-A1
Application number	US-201314412506-A
Country	US
Kind code	A1
Filing date	Jun 13, 2013
Priority date	Jul 6, 2012
Publication date	Jan 7, 2016
Grant date	—

Abstract

The invention relates to an unbonded flexible pipe with a length and a longitudinal axis. The pipe comprises an inner sealing sheath defining a bore, a pressure armor layer, an intermediate sealing sheath and a tensile armor. The pressure armor layer comprises at least one elongate metal element arranged with pressure armor gaps and is arranged in an annulus provided between the inner sealing sheath and the intermediate sealing sheath. The tensile armor is arranged on the outer side of the intermediate sealing sheath. Either the intermediate sealing sheath forms a drainage layer or the unbonded flexible pipe further comprises a drainage layer arranged in the annulus. The drainage layer comprises at least one drainage path arranged along the length of the pipe, wherein the drainage path is in fluid communication with the pressure armor gaps. The drainage layer optionally comprises a perforated tube.

First claim

What is claimed is:

1 - 37 . (canceled)

38 . A unbonded flexible pipe having a length and a longitudinal axis and comprising an inner sealing sheath defining a bore, a pressure armor layer, an intermediate sealing sheath and a tensile armor, wherein the pressure armor layer comprises at least one elongate metal element arranged with pressure armor gaps and is arranged in an annulus provided between said inner sealing sheath and said intermediate sealing sheath, said tensile armor being arranged on the outer side of said intermediate sealing sheath, wherein said intermediate sealing sheath forms a drainage layer or said unbonded flexible pipe further comprises a drainage layer arranged in said annulus, said drainage layer comprises at least one drainage path arranged along the length of the pipe, wherein the drainage path is in fluid communication with said pressure armor gaps and wherein said drainage path is in the form of a perforated tube comprising a plurality of perforations.

39 . The unbonded flexible pipe of claim 38 , wherein said intermediate sealing sheath forms the drainage layer, the intermediate sheath comprises at least one groove shaped channel on the inner side thereof facing the pressure armor layer, and the perforated tube arranged in the groove shaped channel forms the drainage path.

40 . The unbonded flexible pipe of claim 38 , wherein said drainage layer is arranged in said annulus and comprises said at least one drainage path and a polymer panel structure framing said at least one drainage path.

41 . The unbonded flexible pipe of claim 38 , wherein said perforated tube comprises a plurality of perforations facing towards the pressure armor layer.

42 . The unbonded flexible pipe of claim 40 , wherein said polymer panel structure and said perforated tube are not bonded to each other.

43 . The unbonded flexible pipe of claim 40 , wherein said polymer panel structure provides a grove shaped crib for said perforated tube, preferably such that the tube is facing towards the pressure armor layer.

44 . The unbonded flexible pipe of claim 40 , wherein said perforated tube has an outer radial diameter determined in radial direction and said drainage layer has a thickness determined in radial direction, wherein said thickness of said drainage layer is up to about 5 times the outer radial diameter of said perforated tube.

45 . The unbonded flexible pipe of claim 40 , wherein said perforated tube has an outer radial diameter determined in radial direction and said drainage layer has a thickness determined in radial direction, wherein said thickness of said drainage layer is at least about 1.1 times the outer radial diameter of said perforated tube, wherein said panel structure provides a grove shaped crib for said perforated tube, such that the tube is facing towards the pressure armor layer.

46 . The unbonded flexible pipe of claim 45 , wherein said panel structure provides a thermal insulation, the panel structure exhibits a thermal conductivity of about 0.3 W/m·K or less.

47 . The unbonded flexible pipe of claim 38 , wherein said perforated tube has an outer radial diameter determined in radial direction and said drainage layer has a thickness determined in radial direction, wherein said thickness of said drainage layer is at least about 75% the outer radial diameter of said perforated tube.

48 . The unbonded flexible pipe of claim 38 , wherein said drainage layer comprises a plurality of perforated tubes.

49 . The unbonded flexible pipe of claim 38 , wherein said drainage path is arranged to be substantially parallel with the longitudinal axis of the pipe.

50 . The unbonded flexible pipe of claim 38 , wherein said drainage path is arranged to extend helically along the length of the pipe.

51 . The unbonded flexible pipe of claim 38 , wherein said drainage layer comprises a signal transmitting element.

52 . The unbonded flexible pipe of claim 40 , wherein said polymer panel structure is of a material having an elastic modulus E≧1.5 GPa.

53 . The unbonded flexible pipe of claim 40 , wherein said polymer panel structure has a compression stiffness in axial direction of the pipe of at least about 1 GPa/m.

54 . The unbonded flexible pipe of claim 40 , wherein said polymer panel structure comprises reinforcement element(s) such as fibers, solid and/or hollow microspheres, e.g. made from glass, polymer or silica, preferably the polymer panel structure comprises fibres, such as glass fibres, carbon fibres, aramide fibres, silica fibres such as basalt fibres, steel fibres, polyethylene fibres, polypropylene fibres, mineral fibres, and/or any combination thereof.

55 . The unbonded flexible pipe of claim 40 , wherein said polymer panel structure comprises syntactic foam.

56 . The unbonded flexible pipe of claim 38 , wherein said drainage layer is arranged above the pressure armor layer.

57 . The unbonded flexible pipe of any one of claim 38 , wherein said drainage layer is arranged below the pressure armor layer.

58 . The unbonded flexible pipe of claim 38 , wherein said pressure armor layer comprises at least one elongate metal wire which is helically wound and optionally interlocked in adjacent windings, preferably the at least one elongate metal wire is wound with a winding angle to the longitudinal axis of the core part of the pipe which is at least about 55 degrees, preferably at least about 70 degrees, such as at least about 80 degrees.

59 . The unbonded flexible pipe of claim 38 , wherein said unbonded flexible pipe comprises a carcass arranged inside said inner sealing sheath.

60 . The unbonded flexible pipe of claim 38 , wherein said tensile armor comprises at least two cross-wound tensile armor layers, each tensile armor layer comprises a plurality of helically wound elongate armor elements and said tensile armor comprises or consists essentially of composite material and said unbonded flexible pipe comprises an outer protection layer, said outer protection layer is liquid permeable.

Assignees

• Nat Oilwell Varco Denmark Is

Inventors

• Glejbol Kristian

Classifications

• F16L11/082 Primary

  two layers · CPC title

• F16L11/02

  made of fibres or threads, e.g. of textile · CPC title

• F16L11/20 Primary

  Double-walled hoses · CPC title

• F16L11/14

  made of rigid material, e.g. metal or hard plastics · CPC title