Sucker rod apparatus and method

• US 20130039692A1
• Filed: 08/09/2011
• Published: 02/14/2013
• Est. Priority Date: 08/09/2011
• Status: Active Grant

• Current Assignee: Finalrod IP, LLC
• Original Assignee: Russell P. Rutledge Jr
• Inventors: Rutledge, Russell P., Rutledge, Russell P. Jr., Rutledge, Ryan B.
• Granted Patent: US 8,851,162 B2
• Time in Patent Office: Days
• US Class Current: 403/268
• CPC Class Codes: B29C 65/483 Reactive adhesives, e.g. chemically curing adhesives
• CPC Class Codes: B29C 65/4835 Heat curing adhesives
• CPC Class Codes: B29C 65/542 by injection
• CPC Class Codes: B29C 66/12441 being a single wall
• CPC Class Codes: B29C 66/1246 characterised by the female part, i.e. the part comprising the groove
• CPC Class Codes: B29C 66/5261 for forming coaxial connections, i.e. the bars to be joined forming a zero angle relative to each other
• CPC Class Codes: B29C 66/53 Joining single elements to tubular articles, hollow articles or bars
• CPC Class Codes: B29C 66/721 Fibre-reinforced materials B29C66/729 takes precedence
• CPC Class Codes: B29L 2031/06 Rods, e.g. connecting rods , rails, stakes shafts B29L2031/75; poles, masts, posts B29L2031/766
• CPC Class Codes: E21B 17/1071 specially adapted for pump rods, e.g. sucker rods
• CPC Class Codes: F04B 47/02 the driving mechanisms being situated at ground level F04B47/12 takes precedence
• CPC Class Codes: F04B 53/14 Pistons, piston-rods or piston-rod connections
• CPC Class Codes: Y10T 403/47 Molded joint
• CPC Class Codes: Y10T 403/473 Socket or open cup for bonding material
• CPC Class Codes: Y10T 403/70 Interfitted members

Abstract

The present disclosure relates to a fiberglass rod with connectors on each end. Each connector has a rod-receiving receptacle having an open end, a closed end, and axially spaced annular wedge shaped surfaces such that the compressive forces between the rod and the respective connector are defined by the shape of the wedged surfaces.

Claims

1. An end fitting for a sucker rod comprising:

an exterior surface, a closed end, an open end, and an interior surface,

the interior surface comprising a wedge system defining a cavity wherein the wedge system comprises three wedge shaped portions having an apex, a leading edge and a trailing edge, each apex forming a perimeter of equal dimension within the cavity that is the narrowest part of the cavity associated with each wedge shaped portion such that the leading edge is longer than the trailing edge with the leading edge facing the open end and the trailing edge facing the closed end with respect to each wedge shaped portion,

the leading edge is shorter at the closed end a increases progressively from the closed end to the open end thereby compensating for the compression of the sucker rod in the end fitting, the trailing edge is shorter at the closed end a increases progressively from the closed end to the open end thereby compensating for the back pressure associated with the sucker rod in the end fitting,

the first wedge shaped portion proximate to the closed end for receiving compressive forces that are greater than the compressive forces for which the second wedge shaped portion receives, and the second wedge shaped portion receiving compressive forces that are greater than the compressive forces for which the third wedge shaped portion receives, such that the compressive forces create a force differential along the wedge system greater at the closed end of the fitting and decreasing toward the open end of the fitting.

2. The end fitting of claim 1 wherein the wedge system creates different compressive forces on each respective wedge shaped portion thereof with the compressive force being approximately proportional to a length of each edge.

3. The end fitting of claim 2 wherein the compressive force on each edge is directly proportional to the length of each edge.

4. The end fitting of claim 1 wherein the wedge shaped portions are determined by an angle associated the apex between the leading edge and the trailing edge.

5. The end fitting of claim 4 wherein the angle between the leading edge and the trailing edge of each concaved surface is obtuse.

6. The end fitting of claim 1 further comprising a fiber composite rod having an end engaged centrally within the end fitting.

7. The end fitting of claim 6 further comprising a second end fitting engaged with a second end of the fiber composite rod.

8. The end fitting of claim 6 further comprising an epoxy placed in the cavity for bonding with the fiber composite rod in the cavity for fixedly securing the end fitting with the fiber composite rod.

9. The end fitting of claim 8 wherein the epoxy is uniform in thickness between the wedge shaped portions and the fiber composite rod such that the maximum thickness is substantially constant and the minimum thickness is substantially constant.

10. The end fitting of claim 6 further comprising a beveled recess in the closed end for accepting and centrally aligning the fiber composite rod within the end fitting.

11. A sucker rod comprising:

a fiber composite rod having a first end and a second end, and

end fittings on each end of the fiber composite rod for coupling together a plurality of fiber composite rods, the end fitting comprising;

an exterior surface, a closed end, an open end, and an interior surface,

the interior surface comprising a wedge system defining a cavity wherein the wedge system comprises three wedge shaped portions having an apex, a leading edge and a trailing edge, each apex forming a perimeter of equal dimension within the cavity that is the narrowest part of the cavity associated with each wedge shaped portion such that the leading edge is longer than the trailing edge with the leading edge facing the open end and the trailing edge facing the closed end with respect to each wedge shaped portion,

the leading edge is shorter at the closed end a increases progressively from the closed end to the open end thereby compensating for the compression of the sucker rod in the end fitting, the trailing edge is shorter at the closed end a increases progressively from the closed end to the open end thereby compensating for the back pressure associated with the sucker rod in the end fitting,

the first wedge shaped portion proximate to the closed end for receiving compressive forces that are greater than the compressive forces for which the second wedge shaped portion receives, and the second wedge shaped portion receiving compressive forces that are greater than the compressive forces for which the third wedge shaped portion receives, such that the compressive forces create a force differential along the wedge system greater at the closed end of the fitting and decreasing toward the open end of the fitting.

12. The sucker rod of claim 11 wherein the wedge system creates different compressive forces on each respective wedge shaped portion thereof with the compressive force being approximately proportional to a length of each edge.

13. The sucker rod of claim 12 wherein the compressive force on each edge is directly proportional to the length of each edge.

14. The sucker rod of claim 11 wherein the wedge shaped portions are determined by an angle associated the apex between the leading edge and the trailing edge.

15. The sucker rod of claim 14 wherein the angle between the leading edge and the trailing edge of each concaved surface is obtuse.

16. The sucker rod of claim 11 wherein the fiber composite rod having each end engaged centrally within the end fitting.

17. The sucker rod of claim 16 further comprising an epoxy placed in the cavity for bonding with the fiber composite rod in the cavity for fixedly securing the end fitting with the fiber composite rod.

18. The sucker rod of claim 17 wherein the epoxy is uniform in thickness between the wedge shaped portions and the fiber composite rod such that the maximum thickness is substantially constant and the minimum thickness is substantially constant.

19. The sucker rod of claim 16 further comprising a beveled recess in the closed end for accepting and centrally aligning the fiber composite rod within the end fitting.

20. A sucker rod comprising:

a fiber composite rod having a first end and a second end, and

end fittings on each end of the fiber composite rod for coupling together a plurality of fiber composite rods, the end fitting comprising;

an exterior surface, a closed end, an open end, and an interior surface,

the interior surface comprising a wedge system defining a cavity wherein the wedge system comprises an interior, at least one intermediate and an exterior wedge shaped portion, each wedge shaped portion having an apex, a leading edge and a trailing edge, each apex forming a perimeter of equal dimension within the cavity that is the narrowest part of the cavity associated with each wedge shaped portion such that the leading edge is longer than the trailing edge with the leading edge facing the open end and the trailing edge facing the closed end with respect to each wedge shaped portion,

each leading edge is shorter at the closed end a increases progressively from the closed end to the open end thereby compensating for the compression of the sucker rod in the end fitting, each trailing edge is shorter at the closed end a increases progressively from the closed end to the open end thereby compensating for the back pressure associated with the sucker rod in the end fitting,

the interior wedge shaped portion proximate to the closed end for receiving compressive forces that are greater than the compressive forces for which the intermediate wedge shaped portion receives, and the intermediate wedge shaped portion receiving compressive forces that are greater than the compressive forces for which the exterior wedge shaped portion receives, such that the compressive forces create a force differential along the wedge system greater at the closed end of the fitting and decreasing toward the open end of the fitting.

21. The sucker rod of claim 20 wherein the wedge system creates different compressive forces on each respective wedge shaped portion thereof with the compressive force being approximately proportional to a length of each edge.

22. The sucker rod of claim 21 wherein the compressive force on each edge is directly proportional to the length of each edge.

23. The sucker rod of claim 20 wherein the wedge shaped portions are determined by an angle associated the apex between the leading edge and the trailing edge.

24. The sucker rod of claim 23 wherein the angle between the leading edge and the trailing edge of each concaved surface is obtuse.

25. The sucker rod of claim 20 wherein the fiber composite rod has each end engaged centrally within the end fitting.

26. The sucker rod of claim 25 further comprising an epoxy placed in the cavity for bonding with the fiber composite rod in the cavity for fixedly securing the end fitting with the fiber composite rod.

27. The sucker rod of claim 26 wherein the epoxy is uniform in thickness between the wedge shaped portions and the fiber composite rod such that the maximum thickness is substantially constant and the minimum thickness is substantially constant.

28. The sucker rod of claim 25 further comprising a beveled recess in the closed end for accepting and centrally aligning the fiber composite rod within the end fitting.

29. A sucker rod comprising:

a fiber composite rod having a first end and a second end, and

end fittings on each end of the fiber composite rod for coupling together a plurality of fiber composite rods, the end fitting comprising

an exterior surface, a closed end, an open end, and an interior surface,

the interior surface comprising a wedge system defining a cavity wherein the wedge system comprises an interior, at least one intermediate and an exterior wedge shaped portion, each wedge shaped portion having an apex, a leading edge and a trailing edge, each apex forming a perimeter of equal dimension within the cavity that is the narrowest part of the cavity associated with each wedge shaped portion such that the leading edge is longer than the trailing edge with the leading edge facing the open end and the trailing edge facing the closed end with respect to each wedge shaped portion,

each leading edge is shorter at the closed end a increases progressively from the closed end to the open end thereby compensating for the compression of the sucker rod in the end fitting, each trailing edge is shorter at the closed end a increases progressively from the closed end to the open end thereby compensating for the back pressure associated with the sucker rod in the end fitting,

the ratio of the trailing edge to the leading edge of the interior wedge shaped portion is larger than the ratio of the trailing edge to the leading edge of each subsequent adjacent trailing edge to leading edge ratio,

the interior wedge shaped portion proximate to the closed end for receiving compressive forces that are greater than the compressive forces for which the intermediate wedge shaped portion receives, and the intermediate wedge shaped portion receiving compressive forces that are greater than the compressive forces for which the exterior wedge shaped portion receives, such that the compressive forces create a force differential along the wedge system greater at the closed end of the fitting and decreasing toward the open end of the fitting.

30. The sucker rod of claim 29 wherein the wedge system creates different compressive forces on each respective wedge shaped portion thereof with the compressive force being approximately proportional to a length of each edge.

31. The sucker rod of claim 30 wherein the compressive force on each edge is directly proportional to the length of each edge.

32. The sucker rod of claim 29 wherein the wedge shaped portions are determined by an angle associated the apex between the leading edge and the trailing edge.

33. The sucker rod of claim 32 wherein the angle between the leading edge and the trailing edge of each concaved surface is obtuse.

34. The sucker rod of claim 29 wherein the fiber composite rod has each end engaged centrally within the end fitting.

35. The sucker rod of claim 34 further comprising an epoxy placed in the cavity for bonding with the fiber composite rod in the cavity for fixedly securing the end fitting with the fiber composite rod.

36. The sucker rod of claim 35 wherein the epoxy is uniform in thickness between the wedge shaped portions and the fiber composite rod such that the maximum thickness is substantially constant and the minimum thickness is substantially constant.

37. The sucker rod of claim 34 further comprising a beveled recess in the closed end for accepting and centrally aligning the fiber composite rod within the end fitting.

38. A method for manufacturing a sucker rod comprising the steps of:

constructing an end fitting comprising an exterior surface, a closed end, an open end, and an interior surface, the interior surface comprising a wedge system defining a cavity wherein the wedge system comprises an interior, at least one intermediate and an exterior wedge shaped portion, each wedge shaped portion having an apex, a leading edge and a trailing edge, each apex forming a perimeter of equal dimension within the cavity that is the narrowest part of the cavity associated with each wedge shaped portion such that the leading edge is longer than the trailing edge with the leading edge facing the open end and the trailing edge facing the closed end with respect to each wedge shaped portion,

engaging an end of a fiber composite rod into the cavity of the end fitting for creating a symmetrical void between the fiber composite rod and the wedge shaped portions of the end fitting whereby the symmetrical void has symmetry along the longitudinal axis of the fiber composite rod,

injecting an epoxy into the void to bond with the fiber composite rod and to fixedly engage the wedge shaped portions of the wedge system of the end fitting for securing the end fitting to the fiber composite rod such that as the epoxy is uniform in thickness between the wedge shaped portions and the fiber composite rod whereby the maximum thickness is substantially constant and the minimum thickness is substantially constant,

the interior wedge shaped portion proximate to the closed end for receiving compressive forces that are greater than the compressive forces for which the intermediate wedge shaped portion receives, and the intermediate wedge shaped portion receiving compressive forces that are greater than the compressive forces for which the exterior wedge shaped portion receives, such that the compressive forces create a force differential along the wedge system greater at the closed end of the fitting and decreasing toward the open end of the fitting.

39. The method for manufacturing a sucker rod of claim 38 further comprising the step of creating different compressive forces on each respective surface of the wedge shaped portions with the compressive force being approximately proportional to the length of each edge.

40. The method for manufacturing a sucker rod of claim 39 further comprising the step of the compressive force on each surface increasing toward the closed end and decreasing toward the open end.

41. The method for manufacturing a sucker rod of claim 40 wherein the compressive force on each first edge is proportional to the length of each edge.

42. The method for manufacturing a sucker rod of claim 41 wherein the compressive force on each second edge is proportional to the length of each second edge.

43. The method for manufacturing a sucker rod of claim 38 wherein the plurality of wedge shaped portions are determined by the angle associated between the first surface and the second surface of each concaved surface.

44. The method for manufacturing a sucker rod of claim 43 wherein the angle between the first surface and the second surface of each concaved surface is obtuse.

45. The method for manufacturing a sucker rod of claim 38 wherein each wedge shape has a length proportional to the compressive force applied to the wedge shape.

46. The method for manufacturing a sucker rod of claim 38 wherein each wedge shape has a length that increases from the closed end to the open end of the end fitting.

47. The method for manufacturing a sucker rod of claim 38 wherein each wedge shape has a length that decreases from the closed end to the open end of the end fitting.