Flexible pipe and process for production thereof

Patent metadata

Field	Value
Publication number	US-9309998-B2
Application number	US-201113640679-A
Country	US
Kind code	B2
Filing date	Apr 6, 2011
Priority date	Apr 13, 2010
Publication date	Apr 12, 2016
Grant date	Apr 12, 2016

Abstract

The invention relates to a flexible tube of multilayer construction having unbonded layers, wherein at least one layer is formed in that a tape made of a plastic molding compound is spirally wound about a further inner layer, wherein the upper and lower layers of the tape are simultaneously or subsequently welded to each other at overlapping regions. The tube is particularly suitable for offshore application in oil and gas extraction

First claim

The invention claimed is:

1. A process for producing a flexible pipe of multilayer structure with unbonded layers effective for conveying a liquid or gas selected from the group consisting of crude oil, natural gas, methanol, and CO 2 at a temperature of at least 130° C., the process comprising:
forming a layer by winding a tape helically onto a more internal layer, and
simultaneously or subsequently welding an upper sublayer of the tape and a lower sublayer of the tape to one another at an overlap region of no more than about 10% of the width of the tape via introduction of electromagnetic radiation,
wherein the tape comprises a plastics molding composition based on olefinic polymer, polyamide, fluoropolymer, polyphenyl sulphone, polyarylene ether ketone, polyphenylene sulphide, or a polyarylene ether ketone/polyphenylene sulphide blend, the portions of the upper sublayer of the tape and the lower sublayer of the tape not welded to one another at the overlap region being no more than frictionally bonded together,
wherein the electromagnetic radiation absorption properties of the tape differ across the width of the tape,
when helically winding the tape, a more electromagnetic radiation absorbent width of the tape is covered by a more electromagnetic radiation transparent width of the tape, and
at least two of the layers of the multilayer structure are not bonded directly or indirectly together.

2. The process of claim 1 ,
wherein the more internal layer comprises a carcass, a tubular interior lining, or a reinforcing layer.

3. The process of claim 1 ,
wherein the tape comprises a molding composition based on polyamide, fluoropolymer, polyphenyl sulphone, polyarylene ether ketone, polyphenylene sulphide, or a polyarylene ether ketone/polyphenylene sulphide blend.

4. The process of claim 1 , wherein the tape is a single-layer tape or a multilayer tape.

5. The process of claim 4 ,
wherein the tape is a multilayer tape comprising a barrier layer with respect to diffusion of H 2 S or CO 2 .

6. The process of claim 5 ,
wherein the barrier layer comprises an EVOH molding composition.

7. The process of claim 1 , wherein the tape comprises long-fiber reinforcement.

8. The process of claim 1 ,
wherein the welding comprises laser welding or infrared welding the upper sublayer of the tape and a lower sublayer of the tape to one another at the overlap region as radiation passes through the more transparent upper sublayer of the tape.

9. The process of claim 2 ,
wherein the more internal layer comprises a reinforcing layer, and
the reinforcing layer comprises a helically arranged steel wire, a steel profile, or a steel strip.

10. The process of claim 1 ,
wherein a first side of the tape comprises a first molding composition,
a second side of the tape comprises a second molding composition, and
the first and second molding compositions are of identical or similar composition.

11. The process of claim 3 ,
wherein the tape comprises a polyamide, and
monomer units of the polyamide comprise an average of at least 8 carbon atoms.

12. The process of claim 3 ,
wherein the tape comprises a polyarylene ether ketone,
the polyarylene ether ketone comprises units of formulae
(—Ar—X—)

and
(—Ar′—Y—),

each of Ar and Ar′ is a divalent aromatic moiety,
X is an electron-withdrawing group, and
Y is another group.

13. The process of claim 12 , wherein Ar, Ar′, or both, comprise 1,4-phenylene, 4,4′-biphenylene, 1,4-naphthylene, 1,5-naphthylene, 2,6-naphthylene, or any combination thereof.

14. The process of claim 12 , wherein X comprises carbonyl or sulphonyl.

15. The process of claim 12 , wherein Y comprises O, S, CH 2 , or isopropylidene.

16. The process of claim 1 ,
wherein the multilayer structure comprises a reinforcing layer and a plastics layer with no direct or indirect bonding between them.

17. A process for producing a flexible pipe of multilayer structure with unbonded layers effective for conveying a liquid or gas selected from the group consisting of crude oil, natural gas, methanol, and CO 2 at a temperature of at least 130° C., the process comprising:
simultaneously winding two layers of tape helically onto a more internal layer, the upper layer of tape being wound over the lower layer of tape, and
simultaneously or subsequently welding the upper layer of tape and the lower layer of the tape to one another at an overlap region of no more than about 10% of the width of each tape via introduction of electromagnetic radiation,
wherein each layer of tape comprises a plastics molding composition based on olefinic polymer, polyamide, fluoropolymer, polyphenyl sulphone, polyarylene ether ketone, polyphenylene sulphide, or a polyarylene ether ketone/polyphenylene sulphide blend, the portions of the upper layer of tape and the lower layer of tape not welded to one another at the overlap region being no more than frictionally bonded together,
wherein the electromagnetic radiation absorption properties of the lower layer of tape are greater than the electromagnetic radiation absorption properties of the upper layer of tape and the electromagnetic radiation transparent properties of the lower layer of tape is less than the electromagnetic radiation transparent properties of the upper layer of tape, and
at least two of the layers of the multilayer structure are not bonded directly or indirectly together.

18. The process of claim 17 ,
wherein each layer of tape comprises a molding composition based on polyamide, fluoropolymer, polyphenyl sulphone, polyarylene ether ketone, polyphenylene sulphide, or a polyarylene ether ketone/polyphenylene sulphide blend.

19. The process of claim 17 ,
wherein the welding comprises laser welding or infrared welding the upper layer of tape and the lower layer of tape to one another at the overlap region as radiation passes through the more transparent upper layer of tape.

20. The process of claim 17 ,
wherein each layer of tape comprises a polyamide, and
monomer units of the polyamide comprise an average of at least 8 carbon atoms.

Assignees

• Kuhmann Karl
• Dowe Andreas
• Goering Rainer
• Evonik Degussa Gmbh

Inventors

• Kuhmann Karl
• Dowe Andreas
• Goering Rainer

Classifications

• B29K2081/00

  Use of polymers having sulfur, with or without nitrogen, oxygen or carbon only, in the main chain, as moulding material · CPC title

• F16L11/088 Primary

  comprising a combination of one or more layers of a helically wound cord or wire with one or more braided layers · CPC title

• B29K2071/00

  Use of polyethers {, e.g. PEEK, i.e. polyether-etherketone or PEK, i.e. polyetherketone or derivatives thereof}, as moulding material · CPC title

• B29K2027/12

  containing fluorine · CPC title

• B29K2023/00

  Use of polyalkenes {or derivatives thereof} as moulding material · CPC title