Pipe element having a composite pipe and a metal connector

Patent metadata

Field	Value
Publication number	US-10612709-B2
Application number	US-201414786228-A
Country	US
Kind code	B2
Filing date	Apr 4, 2014
Priority date	Apr 22, 2013
Publication date	Apr 7, 2020
Grant date	Apr 7, 2020

Abstract

A pipe element includes a pipe made of fiber-reinforced plastic and at least one metal connector, which is connected to the pipe in such a way that the connection can transmit torques and axial forces. The metal connector has a thread, in particular a conical thread, or a flange, by way of which thread or flange the metal connector can be screwed to another metal connector of an additional pipe element in order to connect two pipe elements. The metal connector surrounds the pipe on the outside by way of a connection region. A counter sleeve is present, which has contact with the inside of the pipe by way of a connection region. The metal connector and the counter sleeve each have a cylindrical thread, by way of which the metal connector and the counter sleeve are screwed to each other.

First claim

The invention claimed is:

1. A pipe element, comprising:
a pipe of fiber-reinforced plastics material, said pipe having a radially outer side and a radially inner side;
a metal connector connected to said pipe to enable torques and axial forces to be transmitted between said pipe and said metal connector, said metal connector being formed with a thread or having a flange for screwing said metal connector to another metal connector of another pipe element in order to connect said metal connector to said another pipe element;
said metal connector surrounding said pipe at the outer side within an outer connection region;
a one-piece counter-sleeve disposed in contact with the radially inner side of said pipe within an inner connection region; and
each of said metal connector and said counter-sleeve being formed with a cylindrical thread by way of which said metal connector and said counter-sleeve are screwed to one another.

2. The pipe element according to claim 1 , wherein said metal connector is formed with a conical thread.

3. The pipe element according to claim 1 , wherein said metal connector is a first metal connector, and comprising a second metal connector disposed at an end of said pipe opposite said metal connector, said second metal connector being connected to said pipe in the same manner as the first metal connector.

4. The pipe element according to claim 1 , wherein said pipe is formed with a further connection region at the outer side which constitutes a face that tapers conically toward the pipe end and which is in contact with said outer connection region of said metal connector, and wherein said outer connection region is constructed as a correspondingly fitting conically shaped face.

5. The pipe element according to claim 4 , wherein an inclination angle of a cone formed at the outer side of the pipe in said further connection region with respect to the metal connector lies between 0.1° and 30° with respect to an axis of said pipe.

6. The pipe element according to claim 1 , wherein said pipe has a connection region at the radially inner side which constitutes a face that tapers conically toward a pipe end and which is in contact with said inner connection region of said counter-sleeve, wherein said region is constructed as a correspondingly fitting conically shaped face.

7. The pipe element according to claim 6 , wherein an inclination angle of a cone at the inner side of said pipe in the connection region with respect to the counter-sleeve lies between 0.1° and 30° with respect to an axis of said pipe.

8. The pipe element according to claim 7 , wherein the inclination angle of the cone at the radially inner side lies between 0.5° and 5° and wherein an inclination angle of a cone formed at the radially outer side of the pipe lies between 0.5° and 5° with respect to the axis of said pipe.

9. The pipe element according to claim 1 , which further comprises an inner pipe formed with a coating of a material which is more resistant than the inner pipe with respect to oil or other chemicals, wherein the pipe is wound on the inner pipe, and wherein the inner pipe has a smaller wall thickness than the pipe.

10. The pipe element according to claim 9 , wherein said inner pipe is formed of metal or fiber-reinforced plastics material and is provided with a coated radially inner side thereof.

11. The pipe element according to claim 1 , which comprises a cable in a wall of said pipe, or between an inner pipe and said pipe, said cable extending from one pipe end to an opposite pipe end and being connected to a connector located inside said metal connector and being configured for producing an electrical connection with respect to another connector or cable in another pipe element when the pipe element is screwed to the other pipe element via said conical thread or said flange.

12. The pipe element according to claim 11 , wherein said counter-sleeve has a protective shield disposed at an end of said counter-sleeve opposite said connection region and constructed so that said connector, when viewed in a radial direction, is located completely between said metal connector and said counter-sleeve.

13. The pipe element according to claim 11 , wherein said counter-sleeve is formed with an axial groove in said cylindrical thread or an axial longitudinal hole in a material below said cylindrical thread, for guiding a cable from said pipe to said connector.

14. The pipe element according to claim 1 , which comprises a torsion prevention device disposed between said counter-sleeve and said metal connector.

15. The pipe element according to claim 14 , wherein said torsion prevention device is a weld seam at an end face of said counter-sleeve or at least one pin inserted in an axial direction.

16. The pipe element according to claim 1 , wherein an inner face of said counter-sleeve has an inner profile extending in a completely smooth continuous manner in an axial direction without edges or steps.

17. A method of producing a pipe element in accordance with claim 1 , the method comprising:
providing a counter-sleeve with a cylindrical thread;
forming a pipe by winding fiber material around a core and thereby winding the fiber material over the counter-sleeve in a connection region with the pipe;
applying matrix material together with or after the fiber material;
thermally processing the pipe together with the counter-sleeve in a furnace, and thereby hardening or consolidating the matrix material; and
screwing a metal connector with a cylindrical thread thereof onto the cylindrical thread of the counter-sleeve;
to thereby produce a pipe element according to claim 1 .

18. The method according to claim 17 , wherein the core is an inner pipe.

19. The method according to claim 17 , which comprises placing a cable in an axial direction from one end to an opposite end of the inner pipe prior to winding the pipe, and fitting a connector onto the counter-sleeve and electrically connecting the connector to the cable before screwing on the metal connector.

20. The method according to claim 17 , which comprises applying a cable axially from one end to another end to layers of the pipe which have already been wound, prior to finishing the pipe by further winding, and fitting a connector on the counter-sleeve and electrically connecting the connector to the cable before screwing on the metal connector.

Assignees

• Voith Patent Gmbh

Inventors

• Bruehler Juergen
• Teichelmann Patrick
• Seip Benjamin

Classifications

• F16L9/128

  Reinforced pipes · CPC title

• E21B17/042

  Threaded · CPC title

• F16L19/06

  in which radial clamping is obtained by wedging action on non-deformed pipe ends · CPC title

• F16L47/14

  Flanged joints · CPC title

• F16L47/24 Primary

  for joints between metal and plastics pipes · CPC title