Enhanced arc control for magnetically impelled butt welding

Patent metadata

Field	Value
Publication number	US-9669483-B2
Application number	US-201414157275-A
Country	US
Kind code	B2
Filing date	Jan 16, 2014
Priority date	Jan 16, 2014
Publication date	Jun 6, 2017
Grant date	Jun 6, 2017

Abstract

Tubulars are joined for subterranean borehole use in the production of hydrocarbons by a technique of magnetically impelled arc butt (MIAB) welding. Large casing can be accommodated and the weld quality is maintained with control over the pattern of arc movement on the end walls by virtue of relative movements of the tubulars as the arc is generated and the magnetic field is applied. One or both tubulars can be manipulated relatively in a variety of direction to control the movements of the arc as the magnetic field induces circular arc movement along the end walls of the tubulars to heat up the ends to the temperature needed to effectively fuse the wall ends together. Movement can be rotational or axial about a fixed axis or lateral with respect to the axes both with and without skewing of the axes. The movements can be combined to obtain the desired track.

First claim

We claim:

1. An arc control method for magnetically impelled butt welding, comprising:
bringing ends of tubulars to be welded adjacent each other for an initial positioning of major longitudinal axes to create a gap therebetween;
producing a condition to create an arc that crosses said gap;
applying a magnetic field to said gap;
moving said arc around on said ends of said tubulars;
angularly skewing said major longitudinal axis of at least one of said tubulars from said initial positioning to obtain a different relative positioning between said tubulars to control the path of said arc on said ends of said tubulars; and
butt welding said tubulars.

2. The method of claim 1 , comprising:
moving both said tubulars at the same time.

3. The method of claim 1 , comprising:
controlling the arc path between an inside and outside wall of said ends of said tubulars.

4. The method of claim 1 , comprising:
guiding the arc path for evenly heating between an inside and outside wall of said ends of said tubulars.

5. The method of claim 1 , comprising:
guiding the arc path for maintaining said arc midway between an inside and outside wall of said ends.

6. The method of claim 1 , comprising:
moving at least one of said tubulars about a fixed axis.

7. The method of claim 1 , comprising:
moving at least one of said tubulars by moving an axis of at least one of said tubulars.

8. The method of claim 1 , comprising:
moving both said tubulars about fixed axes either at the same time or at different times.

9. The method of claim 1 , comprising:
moving both said tubulars by moving an axis of both of said tubulars at the same time or at different times.

10. The method of claim 1 , comprising:
rotating at least one tubular about a fixed axis thereof.

11. The method of claim 1 , comprising:
translating at least one tubular about a fixed axis thereof or by moving said axis from a first to a second position parallel to said first position.

12. The method of claim 7 , comprising:
moving said axis from a first to a second position that is parallel or skewed to said first position.

13. The method of claim 9 , comprising:
moving at least one of said axes from a first position to a second position where said second position is parallel or skewed with respect to said first position.

14. The method of claim 8 , comprising:
moving both tubulars in the same or opposite direction.

15. The method of claim 9 , comprising:
moving the axis of each tubular from a first to a second position where, in said second position, the axis of each tubular is parallel or skewed to the said first respective axis position.

16. The method of claim 1 , comprising:
performing at least two of rotating at least one tubular about a fixed axis thereof,
translating at least one tubular about a fixed axis thereof or by moving said axis from a first to a second position parallel to said first position and
skewing an axis of at least one of said tubulars with respect to the other of said tubulars, at the same time or at different times.

17. The method of claim 1 , comprising:
performing at least two of rotating both tubulars about a fixed axis thereof,
translating both tubulars about a fixed axis thereof or by moving said axis of said tubulars from a first to a second position parallel to said first position and
skewing an axis of both said tubulars with respect to an original position of said axis, at the same time or at different times.

18. The method of claim 16 , comprising:
moving at least one tubular opposite directions at different times.

19. The method of claim 17 , comprising:
moving both said tubulars in the same or different directions at the same or at different times.

20. The method of claim 19 , comprising:
rotating said tubulars in the same direction as each other and in an opposite direction from said movement of said arc.

21. The method of claim 1 , comprising:
modifying said magnetic field to alter the path of said arc to track different end shapes of said tubulars from round.

22. The method of claim 1 , comprising:
using different tubular turning directions or turning frequencies to heat up said ends of the tubulars differently or equally.

23. The method of claim 1 , comprising:
providing said tubulars of different materials.

Assignees

• Baker Hughes Inc

Inventors

• Lehr Joerg
• Brouwer Dominik

Classifications

• B23K9/0282

  for welding tube sections · CPC title

• B23K9/08 Primary

  Arrangements or circuits for magnetic control of the arc · CPC title