GB1602429A

GB1602429A - Apparatus and method for connecting pipes by welding

Info

Publication number: GB1602429A
Application number: GB1779178A
Authority: GB
Original assignee: Hydrotech International Inc
Current assignee: Hydrotech International Inc
Priority date: 1978-05-04
Filing date: 1978-05-04
Publication date: 1981-11-11

Description

(54) APPARATUS AND METHOD FOR CONNECTING PIPES BY WELDING (71) We, HYDROTECH INTERNATIONAL INC., a corporation organized and existing under the laws of the State of Delaware, United States of America, of P.O. Box 40901, Houston, Texas 77040, United States of America, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to an apparatus and method for connecting pipes. More particularly, this invention relates to apparatus and methods for connecting two spaced pipe ends, the axes of which pass through a common point.

Known methods of connecting pipes usually involve using either mechanical pipe coupling tools or welding. The connections are accomplished either by butt welding the pipe ends directly to each other or by sliding mateable coupling members over the pipes and welding the members together.

Neither method of connecting pipes by welding is entirely satisfactory in all situations. In order to butt weld the pipes directly to each other, the ends thereof must be brought into abuttment in substantially perfect axial alignment. This requires the use of massive alignment equipment. With coupling members, some misalignment is tolera ble. therefore eliminating the need for massive alignment equipment, however, these sapling members are joined to the pipes and to each other by fillet welds, which are inherently inferior to butt welds.

It is an aim of the present invention to provide apparatus and methods by which relatively misaligned pipes may be butt welded together in a relatively simple but reliable manner. To this end, the invention provides apparatus for connecting two spaced pipe ends, the axes of which pass through a common point, comprising a pair of substantially tubular coupling members, each having a first end and a second end or securing to the second end of the other coupling member, the second ends having matching circular faces each of which lies in a plane inclined to the axis of the respective coupling member at a non-perpendicular angle whereby the matching faces can be abutted with the axes of the tubular members at any chosen angle within a range determined by the inclination of the planes containing the matching circular faces to the respective coupling members, and a pair of tubes for respective securement to the pipe ends, upon each of which is formed a radially enlarged anchor ring, the tubes being telescopically engageable with the first ends of the coupling members to a limit determined by the anchor rings for securement thereto after alignment of the matching faces.

In preferred embodiments of the invention the second end of each coupling member comprises an enlarged spherically shaped portion, the plane containing the respective circular face also containing the centre of such portion. However, the end portion does ndt need in all cases to be of spherical crosssection: other cross-sections will suffice, so long as the matching faces are circular. By having such circular faced end portion, a pair of such couplings may be abutted and rotated relative to each other, and be butt welded together. By having the face lie on the plane not perpendicular to the axis of the tubular portion and the inclination of the plane containing the matching circular face on one coupling member the same as that on the other, the coupling members may be joined together at an angle of up to twice the angle by which the plane on which the face lies varies from the perpendicular.

The invention also provides a method of connecting two spaced pipe ends, using apparatus as defined above wherein the coupling members are telescopically mounted on the respective tubes; wherein the tubes are welded to the respective pipe ends; wherein the coupling members are rotated about their axes until the matching faces engage with the member axes inclined at the same angle as the axes of the pipe ends, the matching faces welded together; and wherein each coupling members is secured to the tube upon which it is mounted.

In the method of the invention, the coupling members are preferably secured to the tubes by interposing a split sleeve between the first end of each coupling member and the anchor ring on the respective tube; and welding each split sleeve to the respective coupling member first end and anchor ring.

The invention enables butt welds to be used throughout with their inherent advantages.

The invention will now be described by way of example with reference to the accompanying drawings wherein: Figure 1 is a longitudinal central sectional view of one embodiment of the invention showing both tubular members welded in place, with one coupling mounted and the other coupling in position to be mounted, and Figure 2 is a veiw similar to Figure 1 but showing both coupling members mounted and welded in place.

The apparatus illustrated in the drawings comprises a pair of coupling members, designated generally by the numerals 13 and 14, adapted to be slidingly mounted in telescopic fashion over a pair of tubes 15 and 16, each of which is adapted to be butt welded to one of a pair of pipe ends 11 and 12 as by weldments 30 and 31. Coupling member 13 is substantially identical to coupling member 14. Similarly tube 15 is substantially identical to tube 16. Accordingly, descriptions of one of either pair will apply to the other of the pair.

Coupling member 13 is comprised of tubular portion 18 which flares into a hemispherical end portion 19. End portion 19 terminates at a face 20, which lies on a plane intersecting the axis of tubular portion 18 at an angle not equal to 90 . Since end portion 19 is of spherical cross-section, the intersection thereof with any plane passing therethrough defines a circle. Accordingly, face 20 is circular. The circularity achieved by the use of spherical end portion 19 makes it possible for face 20 of coupling member 13 and face 21 of coupling member 14 to be perfectly abutted, and therefor capable of being butt welded together, no matter how coupling members 13 and 14 are rotated in this respect to each other. As the inclination of each face 20, 21 to the axis of its respective coupling member is the same, the members 13 and 14 may be welded together such that the axes thereof intersect each other throughout a range of angles varying from 0. as shown to an angle equal to twice the angle by which the plane upon which each face 20, 21 lies is inclined to its respective coupling member axis. It is contemplated that the angle by which the plane upon which face 20 lies would differ from the perpendicular would be on the order of 10 to 15o.

Accordingly, the axes of coupling members 13 and 14 may be made to intersect at angles up to 20 to 30 . It should be noted that end portion 19 may be of cross-sections other than spherical, so long as face 20 thereof is circular.

Coupling members 13 and 14 are mounted between pipe ends 11 and 12 by means of tubes 15 and 16. Tube 15 is a section of pipe having inside and outside diameters substantially equal to those of pipe 11 and therefore is adapted for butt welding thereto. The outside diameter of tube 15 is such that tubular portion 18 may be slid thereover and rotated thereabout in telescopic fashion.

Coupling member 13 is fixed upon tube 15 by means of anchor ring 17 and an axially split sleeve 22. Anchor ring 17 is a radially enlarged portion of tube 15 located near a junction of tube 15 and pipe 11 and having an outside diameter substantially equal to that of tubular portion 18. Sleeve 22 is a section of pipe axially split into two halves, each of which is adapted to be fitted over tube 15 between anchor ring 17 and an end 23 of tubular portion 18. Sleeve 22 has an inside and an outside diameter substantially equal to those of tubular portion 18 and is therefore capable of being butt welded between anchor ring 17 and end 23.

In order to carry out the method of the invention, pipe ends 11 and 12 are aligned with respect to each other such that the axes thereof generally intersect at a point approximately half way between pipe ends 11 and 12. With pipe ends 11 and 12 so positioned, the end of tube 15 which anchor ring 17 is located is butt welded generally coaxially to pipe end 11. Tube 16 is similarly butt welded to pipe end 12. With tubes 15 and 16 in place, tubular portion I8 is slidingly mounted over tube 15 and moved into general abuttment with anchor ring 17. Coupling member 14 is then similarly mounted over tube 16 in telescopic manner. Coupling members 13 and 14 are then rotated relative to each other until the planes in which faces 20 and 21 lie are parallel to each other. When the planes are parallel, coupling members 13 and 14 are slid toward each other until faces 20 and 21 are in abutting relationship. Faces 20 and 21 are then butt welded together. The connection is completed by placing split sleeves 22 and 24 over tubes 15 and 16 respectively and making annular butt welds 25 and 26, and longitudinal butt welds 27.

The method and apparatus of this invention may be employed either in the afmosphere or under water. The required welds may be made by using any of a number of techniques known to those skilled in the art.

WHAT WE CLAIM IS 1. Apparatus for connecting two spaced pipe ends, the axes of which pass through a common point, comprising a pair of substantially tubular coupling members, each having a first end, and a second end for securing to the second end of the other coupling

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. tubes by interposing a split sleeve between the first end of each coupling member and the anchor ring on the respective tube; and welding each split sleeve to the respective coupling member first end and anchor ring. The invention enables butt welds to be used throughout with their inherent advantages. The invention will now be described by way of example with reference to the accompanying drawings wherein: Figure 1 is a longitudinal central sectional view of one embodiment of the invention showing both tubular members welded in place, with one coupling mounted and the other coupling in position to be mounted, and Figure 2 is a veiw similar to Figure 1 but showing both coupling members mounted and welded in place. The apparatus illustrated in the drawings comprises a pair of coupling members, designated generally by the numerals 13 and 14, adapted to be slidingly mounted in telescopic fashion over a pair of tubes 15 and 16, each of which is adapted to be butt welded to one of a pair of pipe ends 11 and 12 as by weldments 30 and 31. Coupling member 13 is substantially identical to coupling member 14. Similarly tube 15 is substantially identical to tube 16. Accordingly, descriptions of one of either pair will apply to the other of the pair. Coupling member 13 is comprised of tubular portion 18 which flares into a hemispherical end portion 19. End portion 19 terminates at a face 20, which lies on a plane intersecting the axis of tubular portion 18 at an angle not equal to 90 . Since end portion 19 is of spherical cross-section, the intersection thereof with any plane passing therethrough defines a circle. Accordingly, face 20 is circular. The circularity achieved by the use of spherical end portion 19 makes it possible for face 20 of coupling member 13 and face 21 of coupling member 14 to be perfectly abutted, and therefor capable of being butt welded together, no matter how coupling members 13 and 14 are rotated in this respect to each other. As the inclination of each face 20, 21 to the axis of its respective coupling member is the same, the members 13 and 14 may be welded together such that the axes thereof intersect each other throughout a range of angles varying from 0. as shown to an angle equal to twice the angle by which the plane upon which each face 20, 21 lies is inclined to its respective coupling member axis. It is contemplated that the angle by which the plane upon which face 20 lies would differ from the perpendicular would be on the order of 10 to 15o. Accordingly, the axes of coupling members 13 and 14 may be made to intersect at angles up to 20 to 30 . It should be noted that end portion 19 may be of cross-sections other than spherical, so long as face 20 thereof is circular. Coupling members 13 and 14 are mounted between pipe ends 11 and 12 by means of tubes 15 and 16. Tube 15 is a section of pipe having inside and outside diameters substantially equal to those of pipe 11 and therefore is adapted for butt welding thereto. The outside diameter of tube 15 is such that tubular portion 18 may be slid thereover and rotated thereabout in telescopic fashion. Coupling member 13 is fixed upon tube 15 by means of anchor ring 17 and an axially split sleeve 22. Anchor ring 17 is a radially enlarged portion of tube 15 located near a junction of tube 15 and pipe 11 and having an outside diameter substantially equal to that of tubular portion 18. Sleeve 22 is a section of pipe axially split into two halves, each of which is adapted to be fitted over tube 15 between anchor ring 17 and an end 23 of tubular portion 18. Sleeve 22 has an inside and an outside diameter substantially equal to those of tubular portion 18 and is therefore capable of being butt welded between anchor ring 17 and end 23. In order to carry out the method of the invention, pipe ends 11 and 12 are aligned with respect to each other such that the axes thereof generally intersect at a point approximately half way between pipe ends 11 and 12. With pipe ends 11 and 12 so positioned, the end of tube 15 which anchor ring 17 is located is butt welded generally coaxially to pipe end 11. Tube 16 is similarly butt welded to pipe end 12. With tubes 15 and 16 in place, tubular portion I8 is slidingly mounted over tube 15 and moved into general abuttment with anchor ring 17. Coupling member 14 is then similarly mounted over tube 16 in telescopic manner. Coupling members 13 and 14 are then rotated relative to each other until the planes in which faces 20 and 21 lie are parallel to each other. When the planes are parallel, coupling members 13 and 14 are slid toward each other until faces 20 and 21 are in abutting relationship. Faces 20 and 21 are then butt welded together. The connection is completed by placing split sleeves 22 and 24 over tubes 15 and 16 respectively and making annular butt welds 25 and 26, and longitudinal butt welds 27. The method and apparatus of this invention may be employed either in the afmosphere or under water. The required welds may be made by using any of a number of techniques known to those skilled in the art. WHAT WE CLAIM IS

1. Apparatus for connecting two spaced pipe ends, the axes of which pass through a common point, comprising a pair of substantially tubular coupling members, each having a first end, and a second end for securing to the second end of the other coupling

member, the second ends having matching circular faces each of which lies in a plane inclined to the axis of the respective coupling member at a non-perpendicular angle whereby the matching faces can be abutted with the axes of the tubular members at any chosen angle within a range determined by the inclination of the planes containing the matching circular faces to the respective coupling members, and a pair of tubes for respective securement to the pipe ends, upon each of which is formed a radially enlarged anchor ring, the tubes being telescopically engageable with the first ends of the coupling members to a limit determined by the anchor rings for securement thereto after alignment of the matching faces.

2. Apparatus according to Claim 1 wherein the inclination of the plane containing the matching circular face on one coupling member is the same as that on the other, said range being between zero and twice said inclination.

3. Apparatus according to Claim 1 or Claim 2 wherein the second end of each coupling member comprises an enlarged spherically shaped portion, the plane containing the respective circular face also containing the centre of such portion.

4. Apparatus according to any preceding claim including a pair of axially split sleeves for interposing between each anchor ring and the respective coupling member.

5. Apparatus according to any preceding claim wherein the anchor ring and coupling member are of substantially equal thickness.

6. Apparatus for joining together two spaced pipe ends substantially as described herein with reference to the accompanying drawing.

7. A pipe connection made using apparatus according to any preceding claim.

8. A method of connecting two spaced pipe ends, the axes of which pass through a common point, using apparatus according to any preceding claim wherein the coupling members are telescopically mounted on the respective tubes; wherein the tubes are welded to the respective pipe ends; wherein the coupling members are rotated about their axes until the matching faces engage with the member axes inclined at the same angle as the axes of the pine ends, the matching faces welded together; and wherein each coupling members is secured to the tube upon which it is mounted.

9. A method according to claim 8 wherein the coupling members are secured to the tubes by interposing a split sleeve between the first end of each coupling member and the anchor ring on the respective tube; and welding each split sleeve to the respective coupling member first end and anchor ring.

10. A method according to Claim 9 including the step of welding the sleeves across the splits therein.

11. A method according to any of Claims 8 to 10 wherein each weld is a butt weld.

12. A method of connecting two spaced pipe ends substantailly as described herein with reference to the accompanying draw ings.