Cabling system corrugated centertube umbilical

Patent metadata

Field	Value
Publication number	US-9920598-B2
Application number	US-201113233067-A
Country	US
Kind code	B2
Filing date	Sep 15, 2011
Priority date	Sep 30, 2010
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

An umbilical ( 2 ) has a center tube ( 4 ) that is a steel tube, and that the cross section of the center tube ( 4 ) at the extremity of the umbilical ( 2 ) is made corrugated on a length that extends substantially from the extremity to a distance from the extremity so that fatigue strain on non corrugated parts of the steel tube is avoided when the extremity of the umbilical ( 2 ) is inserted into a bend stiffener ( 1 ).

First claim

The invention claimed is:

1. A platform comprising:
a topside hang-off;
a bend stiffener is fixed to the topside hang-off and extends vertically below said topside hang-off, said bend stiffener is conically tapered with a wide end on the upside near the topside hang-off and a thin end on the other side; and
an umbilical having a center steel tube the upper end of which is also fixed to the topside hang-off, said umbilical extending downward through said bend stiffener,
wherein the cross section of the center steel tube of said umbilical is corrugated in an upper part beginning at the upper end where said umbilical is fixed to the topside hang-off, and where said umbilical extends through said bend stiffener, and remaining corrugated for a length which is less than a total length of said bend stiffener at which point said cross section of the center steel tube is no longer corrugated, so that said center tube gets less stiff inside the bend stiffener.

2. The platform as in claim 1 , wherein said center tube is made of Super Duplex steel.

3. The platform as in claim 1 , wherein said center tube is sheathed with a polyethylene sheath.

4. The platform as in claim 3 , wherein a volume between the corrugated part of the center tube and the polyethylene sheath is filled with elastomer or soft polymer.

5. The platform according to claim 1 , wherein the cross section of the umbilical center steel tube is corrugated for a length that is 70% of the total length of said bend stiffener.

6. The platform as claimed in claim 1 , wherein the center tube is produced by welding together tube parts of 20 to 30 meters.

Assignees

• Lund Sjur Kristian
• Nexans

Inventors

• Lund Sjur Kristian

Classifications

• E21B17/017

  Bend restrictors for limiting stress on risers · CPC title

• E21B17/01

  Risers · CPC title

• F16L9/147

  comprising only layers of metal and plastics with or without reinforcement · CPC title

• F16L11/22

  Multi-channel hoses · CPC title

• F16L11/15

  corrugated (F16L11/16 takes precedence) · CPC title