Deformable pipe coupling having multiple radii of curvature

• US 20080048444A1
• Filed: 06/07/2006
• Published: 02/28/2008
• Est. Priority Date: 06/07/2006
• Status: Active Grant

• Current Assignee: Victaulic Company
• Original Assignee: Victaulic Company
• Inventors: Madara, Scott D., Porter, Michael V., Dole, Douglas R., Haney, Craig, Pierce, John W.
• Granted Patent: US 7,726,703 B2
• Time in Patent Office: Days
• US Class Current: 285/367
• CPC Class Codes: F16L 17/04 with longitudinally split or divided sleeve
• CPC Class Codes: F16L 21/065 tightened by tangentially-arranged threaded pins
• CPC Class Codes: F16L 23/08 connection by tangentially arranged pin and nut
• CPC Class Codes: Y10T 29/49936 Surface interlocking
• CPC Class Codes: Y10T 29/49954 Fastener deformed after application

Abstract

A pipe coupling for joining pipe elements end-to-end is disclosed. The pipe coupling is formed of segments attached to one another circumferentially straddling the pipe elements. The segments are formed from sub-sections connected to one another end-to-end. Each sub-section has a surface region disposed to engage the outer surfaces of the pipe elements. Each surface region has a different radius of curvature from a surface region on a neighboring sub-section. The radii are selected so that when the coupling segments are deformed around the pipe elements, portions of surface regions of selected sub-sections contact the pipe elements, while portions of surface regions of those sub-sections between the selected portions remain in spaced relation away from the pipe elements. A constant and minimal torque is required to bolt the segments together as a result.

Claims

1. A pipe coupling segment, positionable straddling facing ends of a pair of pipe elements for securing said pipe elements together in end-to-end relationship, wherein said ends of said pipe elements have an outer surface of substantially cylindrical profile, said coupling segment comprising:

a plurality of sub-sections attached to one another end-to-end, each said sub-section having a surface region of a different radius of curvature from an adjacent surface region on an adjacent sub-section, said surface regions being disposed to interface circumferentially with the outer surfaces of said pipe elements; and

connection members positioned at opposite ends of said coupling segment for adjustably connecting said coupling segment to a mating coupling segment, at least one of said connection members being adjustably tightenable for drawing said coupling segment and said mating coupling segment toward one another, said coupling segment being deformable upon adjustable tightening of said connection member so as to engage said surface regions with the outer surfaces of said pipe elements at a first contact point located about midway between said opposite ends of said coupling segment and at second and third contact points located at said opposite ends of said coupling segment.

2. A coupling segment according to claim 1, wherein said surface regions between said contact points are in spaced relation away from said outer surfaces of said pipe elements when said contact points engage said outer surfaces of said pipe elements.

3. A coupling segment according to claim 1, wherein said surface region on at least one of said sub-sections has an infinite radius of curvature.

4. A coupling segment according to claim 3, wherein said one sub-section is positioned at a midpoint between said opposite ends of said coupling segment.

5. A coupling segment according to claim 4, wherein said surface regions are symmetrically disposed about the midpoint of said coupling segment.

6. A coupling segment according to claim 1, wherein said connection members project outwardly from said opposite ends of said coupling segment, said connection members being adapted to receive fasteners adjustably joining said connection members to connection members on said mating coupling segment, said fasteners being adjustably tightenable for drawing said surface regions of said sub-sections into engagement with said outer surfaces of said pipe elements.

7. A coupling segment according to claim 1, wherein said surface region located midway between said opposite ends of said coupling segment projects radially inwardly.

8. A coupling segment according to claim 1, comprising a pair of said surface regions located on opposite sides of a midpoint between said opposite ends of said coupling segment, said pair of said surface regions projecting radially inwardly.

9. A coupling segment according to claim 1, wherein two of said surface regions intersect midway between said opposite ends of said coupling segment, said surface regions forming a cusp projecting radially inwardly.

10. A coupling segment according to claim 1, wherein said surface regions are interconnected on each said segment to form a continuous curve.

11. Interconnectable pipe coupling segments, each positionable for straddling facing ends of a pair of pipe elements for securing said pipe elements together in end-to-end relationship, said pipe elements having end surfaces of substantially cylindrical profile wherein each said coupling segment is subdivided into a plurality of sub-sections including a first sub-section disposed at about the midpoint of each said coupling segment and a plurality of second sub-sections on either side of said first subsection, said sub-sections having surface regions disposed to interface with said end surfaces of said pipe elements, said surface region of said first sub-section being planar, said surface regions of said second sub-sections being arcuate.

12. Coupling segments according to claim 11, wherein said surface region on each of said second sub-sections has a different radius of curvature from said surface region on an adjacent sub-section.

13. Coupling segments according to claim 11, wherein said surface region on said first sub-section projects radially inwardly.

14. Coupling segments according to claim 11, wherein said coupling segments are deformable so as to engage said surface regions with the outer surfaces of said pipe elements at a first contact point located about midway between opposite ends of said coupling segments and at second and third contact points located at said opposite ends of said coupling segments, said surface regions between said contact points being in spaced relation away from said outer surfaces of said pipe elements when said contact points engage said outer surfaces of said pipe elements.

15. Coupling segments according to claim 11, wherein said surface regions are interconnected on each said segment to form a continuous curve.

16. Interconnectable pipe coupling segments, each positionable for straddling facing ends of a pair of pipe elements for securing said pipe elements together in end-to-end relationship, wherein said ends of said pipe elements have an outer surface of substantially cylindrical profile and wherein each said coupling segment comprises:

first, second and third sub-sections, said second and said third sub-sections being attached to opposite ends of said first sub-section, said sub-sections each having a surface region disposed to interface circumferentially with the outer surfaces of said pipe elements, said surface region of said first sub-section having a radius of curvature greater than said surface regions on either of said second and third sub-sections; and

connection members positioned at opposite ends of said coupling segments for adjustably connecting said coupling segments to one another, said connection members being adjustably tightenable for drawing said coupling segments toward one another, said coupling segments being deformable upon adjustable tightening of said connection members so as to engage said surface regions with the outer surfaces of said pipe elements at a first contact point located about midway between said opposite ends and at second and third contact points located at said opposite ends of said coupling segments.

17. Coupling segments according to claim 16, wherein said surface regions between said contact points are in spaced relation away from said outer surfaces of said pipe elements when said contact points engage said outer surfaces of said pipe elements.

18. Coupling segments according to claim 16, wherein said surface region of said first sub-section has an infinite radius of curvature.

19. Coupling segments according to claim 16, further comprising additional sub-sections attached to said second and third sub-sections, each of said additional sub-sections having an additional surface region disposed to interface circumferentially with the outer surfaces of said pipe elements, each said additional surface region having a different radius of curvature from a surface region on an adjacent sub-section.

20. Coupling segments according to claim 19, wherein said surface regions are symmetrically disposed about the midpoint of said coupling segment.

21. Coupling segments according to claim 16, wherein said connection members project outwardly from opposite ends of each of said coupling segments, said projecting connection members being adapted to receive fasteners adjustably joining said connection members, said fasteners being adjustably tightenable for drawing said surface regions of said sub-sections together into engagement with said outer surfaces of said pipe elements.

22. Coupling segments according to claim 16, wherein said surface regions on at least one of said coupling segments, taken together, subtend a total angle of less than 180°

, each said surface region having a radius of curvature greater than the radius of curvature of said outer surfaces of said pipe elements.

23. Coupling segments according to claim 16, wherein said surface region on said first sub-section projects radially inwardly.

24. Coupling segments according to claim 16, wherein said surface regions are interconnected on each said segment to form a continuous curve.

25. A pipe coupling assembly for securing pipe elements together in end-to-end relationship, said ends of said pipe elements having an outer surface of substantially cylindrical profile, said coupling assembly comprising:

a plurality of coupling segments connected in end-to-end relationship and positionable straddling facing ends of a pair of said pipe elements, each said coupling segment comprising;

a plurality of sub-sections attached to one another end-to-end, each said sub-section having a surface region of a different radius of curvature from said surface region on an adjacent sub-section, said surface regions being disposed to interface circumferentially with the outer surfaces of said pipe elements; and

connection members positioned at opposite ends of said coupling segments for adjustably connecting said coupling segments to one another, said connection members being adjustably tightenable for drawing said coupling segments toward one another, said coupling segments being deformable upon adjustable tightening of at least one of said connection members so as to engage said surface regions with the outer surfaces of said pipe elements at a first contact point located about midway between said opposite ends of said coupling segments, and at second and third contact points located at said opposite ends of said coupling segments.

26. A coupling assembly according to claim 25, wherein said surface regions between said contact points are in spaced relation away from said outer surfaces of said pipe elements when said contact points engage said outer surfaces of said pipe elements.

27. A coupling assembly according to claim 25, comprising a pair of said coupling segments.

28. A coupling assembly according to claim 27, wherein one of said sub-sections has an infinite radius of curvature.

29. A coupling assembly according to claim 28, wherein said one sub-section is positioned at a midpoint between opposite ends of at least one of said coupling segments.

30. A coupling assembly according to claim 29, wherein said surface regions are symmetrically disposed about the midpoint of at least one of said coupling segments.

31. A coupling assembly according to claim 27, wherein said connection members project outwardly from said opposite ends of each of said coupling segments, said projecting connection members being adapted to receive fasteners for adjustably joining said connection members to one another, said fasteners being adjustably tightenable for drawing said surface regions of said sub-sections into engagement with said outer surfaces of said pipe elements.

32. A coupling assembly according to claim 25, wherein said surface regions on at least one of said coupling segments, taken together, subtend a total angle of less than 180°

, each said surface region having a radius of curvature greater than the radius of curvature of said outer surfaces of said pipe elements.

33. A coupling assembly according to claim 25, wherein said surface region located midway between said opposite ends of at least of said coupling segments projects radially inwardly.

34. A coupling assembly according to claim 25, wherein said surface regions are interconnected on each said segment to form a continuous curve.

35. A pipe coupling assembly for securing pipe elements together in end-to-end relationship, said ends of said pipe elements having an outer surface of substantially cylindrical profile, said coupling assembly comprising:

a plurality of coupling segments connected in end-to-end relationship and positionable straddling facing ends of a pair of said pipe elements, each said coupling segment comprising;

first, second and third sub-sections, said second and said third sub-sections being attached to opposite ends of said first sub-section, said sub-sections each having a surface region disposed to interface circumferentially with the outer surfaces of said pipe elements, said surface region of said first sub-section having a radius of curvature greater than said surface regions on either of said second and third sub-sections; and

connection members positioned at opposite ends of said coupling segments for adjustably connecting said coupling segments to one another, said connection members being adjustably tightenable for drawing said coupling segments toward one another, said coupling segments being deformable upon adjustable tightening of at least one of said connection members so as to engage said surface regions with the outer surfaces of said pipe elements at a first contact point located about midway between said opposite ends and at second and third contact points located at said opposite ends of said coupling segments.

36. A coupling assembly according to claim 35, wherein said surface regions between said contact points are in spaced relation away from said outer surfaces of said pipe elements when said contact points engage said outer surfaces of said pipe elements.

37. A coupling assembly according to claim 35, comprising a pair of said coupling segments.

38. A coupling assembly according to claim 37, wherein said first sub-section on at least one of said coupling segments has an infinite radius of curvature.

39. A coupling assembly according to claim 38, wherein said first sub-section is positioned at a midpoint between said opposite ends of at least one of said coupling segments.

40. A coupling assembly according to claim 39, wherein said surface regions are symmetrically disposed about the midpoint of at least one of said coupling segments.

41. A coupling assembly according to claim 37, further comprising additional sub-sections attached to said second and third sub-sections, each of said additional sub-sections having a different radius of curvature from an adjacent sub-section.

42. A coupling assembly according to claim 41, wherein said surface regions are symmetrically disposed about midpoints of at least one of said coupling segments.

43. A coupling assembly according to claim 37, wherein said connection members project outwardly from opposite ends of each of said coupling segments, said projecting connection members being adapted to receive fasteners for adjustably joining said connection members to one another, said fasteners being adjustably tightenable for drawing said surface regions of said sub-sections into engagement with said outer surfaces of said pipe elements.

44. A coupling assembly according to claim 35, wherein said surface regions on at least one of said coupling segments, taken together, subtend a total angle of less than 180°

, each of said surface regions having a radius of curvature greater than the radius of curvature of said outer surfaces of said pipe elements.

45. A coupling assembly according to claim 35, wherein said surface region on said first sub-section on at least one of said coupling segments projects radially inwardly.

46. A coupling assembly according to claim 35, wherein said surface regions on each said segment are interconnected to form a continuous curve.

47. In combination, a pipe coupling assembly and a pair of pipe elements, said pipe coupling assembly for securing said pipe elements to one another in end-to-end relationship, said pipe elements having an outer surface of substantially cylindrical profile, said coupling assembly comprising:

a plurality of coupling segments connected in end-to-end relationship and positioned straddling facing ends of a pair of said pipe elements, each said coupling segment comprising;

a plurality of sub-sections attached to one another end-to-end, each said sub-section having a surface region of a different radius of curvature from said surface region on an adjacent sub-section, said surface regions being disposed to interface circumferentially with the outer surfaces of said pipe elements; and

connection members positioned at opposite ends of said coupling segments for adjustably connecting said coupling segments to one another, at least one of said connection members being adjustably tightenable for drawing said coupling segments toward one another, said coupling segments being deformed upon adjustable tightening of said connection member bringing said surface regions into engagement with the outer surfaces of said pipe elements at a first contact point located about midway between said opposite ends of said coupling segments, and at second and third contact points located at said opposite ends of said coupling segments.

48. A combination according to claim 47, wherein said surface regions between said contact points are in spaced relation away from said outer surfaces of said pipe elements when said contact points engage said outer surfaces of said pipe elements.

49. A combination according to claim 47, wherein said coupling assembly comprises a pair of said coupling segments.

50. A combination according to claim 49, wherein one of said sub-sections on at least one of said coupling segments has an infinite radius of curvature.

51. A combination according to claim 50, wherein said one sub-section is positioned at a midpoint between opposite ends of said coupling segment.

52. A combination according to claim 51, wherein said surface regions are symmetrically disposed about the midpoint of at least one of said coupling segments.

53. A combination according to claim 49, further comprising circumferential grooves positioned in said end portions of said pipe elements, said outer surfaces of said pipe elements being at least in part included within said grooves, said coupling segments being deformable upon adjustable tightening of said connection members so as to engage said surface regions with the outer surfaces of said pipe elements within said grooves for joining said pipe elements in said end-to-end relation.

54. A combination according to claim 47, wherein said surface regions are interconnected on each said segment to form a continuous curve.

55. A pipe coupling segment, positionable straddling facing ends of a pair of pipe elements for securing said pipe elements together in end-to-end relationship, wherein said ends of said pipe elements have an outer surface of substantially cylindrical profile, said coupling segment comprising:

first and second sub-sections attached to one another end-to-end, each said sub-section having a surface region with a radius of curvature, said first and second sub-sections intersecting at a point midway between opposite ends of said coupling segment, said surface regions forming a cusp projecting radially inwardly, said surface regions being disposed to interface circumferentially with the outer surfaces of said pipe elements; and

connection members positioned at opposite ends of said coupling segment for adjustably connecting said coupling segment to a mating coupling segment, at least one of said connection members being adjustably tightenable for drawing said coupling segment and said mating coupling segment toward one another, said coupling segment being deformable upon adjustable tightening of said connection member so as to engage said surface regions with the outer surfaces of said pipe elements at a first contact point located at said cusp, and at second and third contact points located at said opposite ends of said coupling segment.

56. A pipe coupling segment according to claim 55, wherein said first and second sub-sections have the same radius of curvature.

57. A method of securing facing end portions of pipe elements together in end-to-end relationship wherein said end portions of said pipe elements have an outer surface of substantially cylindrical profile, said method comprising:

providing a pipe coupling assembly having a pair of coupling segments attached to one another end-to-end surrounding a central space, said coupling segments having surface regions disposed to interface circumferentially with the outer surfaces of said pipes;

inserting said end portions of said pipe elements into said central space;

moving said coupling segments toward one another so as to first engage said surface regions of said coupling segments with said outer surfaces of said pipe elements at a first contact point located between opposite ends of said coupling segments; and

deforming said coupling segments so as to next engage second and third surface regions, positioned at said opposite ends of said coupling segments, with said outer surfaces of said pipe elements.

58. A method according to claim 57, further including deforming said coupling segments so that surface regions intermediate said first and second contact points and intermediate said first and third contact points are spaced apart from said outer surfaces of said pipe elements.

59. A method of designing a coupling segment positionable for straddling facing ends of a pair of pipe elements for securing said pipe elements together in end-to-end relationship, wherein said ends of said pipe elements have an outer surface of substantially cylindrical profile, said method comprising:

creating a mathematical model of said segment, said model having a first undeformed shape;

deforming said model to a first deformed shape;

modifying said model so that said first deformed shape becomes a second undeformed shape;

deforming said model so that first and second points thereon coincide with a curve representing said outer surface of said pipe elements; and

adjusting the position of a plurality of third points on said model between said first and second points so that said third points are positioned in spaced relation away from said curve.