Split ball valve
A split ball valve that may be positioned in a production string of line pipe, casing, or tubing. The split ball valve comprises a lower valve assembly and an upper valve assembly. Each of two valve doors in the lower valve assembly is connected to a pinion gear that intermeshes with racks on the upper valve assembly. The upper valve assembly can be vertically displaced relative to the lower valve assembly. A spring keeps the upper valve assembly extended away from the lower valve assembly and thus keeps the valve doors closed. When a downward force is applied to the upper valve assembly, the upper valve assembly is downwardly displaced causing the pinion gears to rotate, which opens the valve doors. The valve doors recede into cavities in the valve body. When open, the split ball valve is fully ported.
The present invention relates generally to piping valves and specifically to a down hole ball valve operated by vertical displacement of an independent string of casing or tubing.
BACKGROUND OF THE INVENTIONWhen drilling or producing a subterranean well, it is often desirable to stop the flow of drilling or production fluid within the production line pipe, casing, or tubing. For example, a drilling engineer may want to stop the flow of drilling or production fluid within the line pipe, casing, or tubing in order to stop the flow of drilling or production fluid into a concentric string of casing or tubing. A drilling engineer may also want to stop the flow of drilling or production fluid within the line pipe, casing, or tubing in order to stop the circulation of drilling or production fluid within a section of the well bore. The most efficient method for stopping the flow of drilling or production fluid within the line pipe, casing, or tubing is to install a valve in the circulation path of the drilling or production fluid.
The location of the valve within the circulation path of the drilling or production fluid can be a critical component in controlling the drilling or production operations. One of the options is to place the valve at the surface in the line pipe. Placing the valve at the surface in the line pipe is advantageous because the valve can be easily actuated. However, placing the valve at the surface limits the control of the drilling or production fluid operations to the well bore as a whole. In other words, when the valve is located at the surface, the drilling engineer cannot independently control the drilling or production fluid at different depths within the well bore. Instead, the drilling engineer must control all the drilling or production fluid in the well bore using the valve at the surface. Allowing a drilling engineer to control the flow of drilling or production fluid at different depths within the well bore is an important feature in well control. Thus, it is preferable to locate the valve down hole (i.e. within the well bore) so that the drilling engineer may independently control different sections of the well bore. Therefore, a need exists for a valve that can be located down hole in the production string.
When a valve is located in a production string of casing or tubing, the valve encounters conditions unique to drilling and production operations. For example, when drilling or producing a well, the casing or tubing string is subjected to high levels of compressive and tensile stress. The valve must be able to withstand these high stress levels without failing. Additionally, when drilling a well using a casing or tubing string, the drill string rotates with a high rate of speed within the string of casing or tubing. When drilling a well using this configuration, the drill string frequently contacts the casing or tubing string, imparting rotational stress onto the casing or tubing string. Because it is not preferable to have a valve accidentally actuated by the rotating drill string, the valve must not be operated by rotational movement. In other words, the down hole valve must be operated only by tension or compression of the string of casing or tubing. Therefore, a need exists for a down hole valve that is operated by tension or compression of the string of casing or tubing.
In addition to being located within the string of casing or tubing, the open valve must not impede the flow of drilling or production fluid through the string of casing or tubing. The drilling or production fluid pressure is a critical factor when maintaining control of the well. If the drilling or production fluid pressure drops below the reservoir pressure, then the formation can blowout into the well bore and create a hazardous condition. Several types of valves, such as globe valves (See
The prior art has previously addressed the need to place a ball valve in the circulation path of the drilling or production fluid. For example, U.S. Pat. No. 3,589,667 (the '667 patent) entitled “Combination Well Blowout Preventer” discloses a ball valve located in the drilling or production fluid circulation path. The ball valve in the '667 patent is located in the control head assembly at the surface. U.S. Pat. No. 4,703,807 (the '807 patent) entitled “Rotatable Ball Valve Apparatus and Method” discloses a similar ball valve located in the control head assembly. While the '667 patent and the '807 patent disclose a ball valve that can be installed in the circulation path of the drilling or production fluid, the '667 patent and the '807 patent do not disclose a ball valve that can be placed down hole. Therefore, a need exists for a ball valve that can be installed down hole in the circulation path of the drilling or production fluid.
Consequently, a need exists for a down hole valve installed in the circulation path of the drilling or production fluid. The need extends a down hole valve that is able to withstand high levels of compressive and tensile stress and is operable only by compression or tension. Finally, a need exists for a down hole valve that is fully ported when the valve is open.
SUMMARY OF THE INVENTIONThe present invention, which meets the needs identified above, is a split ball valve positioned down hole (i.e. in a production string in a well bore). The split ball valve comprises an upper valve assembly and a lower valve assembly. The upper valve assembly comprises an upper housing, an upper collar, a plurality of longitudinal supports, and a lower collar. The lower valve assembly comprises a lower housing, a valve body comprising a valve lower body and a valve upper body, two pinion gears, and two valve doors. The two valve doors are located within the valve body. Each of the valve doors are connected to a pinion gear that extends out of the valve body. The pinion gears intermesh with racks on the plurality of longitudinal supports. The longitudinal supports are affixed to a lower collar, an upper collar, and an upper housing. The upper valve assembly can be vertically displaced relative to the lower valve assembly. A spring is positioned between the lower collar and a lower housing collar. The spring keeps the upper valve assembly extended away from the lower valve assembly and thus keeps the valve doors closed.
When a downward force is applied to the upper valve assembly, the upper housing, upper collar, longitudinal supports, and lower collar are displaced downward relative to the lower valve assembly. The downward displacement compresses the spring. The downward displacement also causes the pinion gears to intermesh with the racks on the longitudinal supports. The intermeshing of the pinion gears and racks causes the pinion gears to rotate, which opens the valve doors. The valve doors recede into cavities in the valve body. When the valve doors are open, the split ball valve is fully ported and does not redirect the flow of drilling or production fluid around structures within the valve assembly. Releasing the downward pressure on the upper valve assembly causes the valve doors to close.
BRIEF DESCRIPTION OF THE DRAWINGSThe novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:
As used herein, the term “casing” shall mean a plurality of connected cylindrical members that are permanently affixed in the well bore and are used in drilling and production operations.
As used herein, the term “drill pipe” shall mean a plurality of connected cylindrical members that are connected to a drill bit and are rotated to drill the well bore.
As used herein, the term “line pipe” shall mean a plurality of connected cylindrical members that are positioned on the surface and are used to transport drilling and production fluid to/from the well bore.
As used herein, the term “tubing” shall mean a plurality of connected cylindrical members that are removably positioned within the well bore and are used in production operations.
One of the components of split ball valve 100 is the lower valve assembly. The lower valve assembly is cylindrical in shape and comprises lower housing 104, the valve body, pinion gears 116, and valve doors (not shown in
Another component of split ball valve 100 is upper valve assembly. Upper valve assembly is cylindrical in shape and comprises upper housing 102, upper collar 120, longitudinal supports 114, and lower collar 108. The upper portion of upper housing 102 screws onto the production string or line pipe (not shown). The lower portion of upper housing 102 screws onto upper collar 120. The interior of the upper valve assembly is sized for sliding engagement with the exterior of the lower valve assembly.
Upper housing 102 and lower housing 104 connect together via upper collar 120, longitudinal supports 114, and lower collar 108. Upper collar 120 is affixed to upper housing 102. Extending downwardly from upper collar 120 are a plurality of longitudinal supports 114. Two of longitudinal supports 114 on opposite sides of split ball valve 100 contain a rack that intermeshes with pinion gear 116. Longitudinal supports 114 are affixed to lower collar 108, which is free to slide along the upper portion of lower housing 104. Spring 106 keeps lower collar 108, and thus longitudinal supports 114, upper collar 120, and upper housing 102 extended away from lower housing 104 in the absence of downward force from the surface exceeding the spring constant of spring 106. Persons of ordinary skill in the art are aware of how to choose an appropriate spring for a particular purpose based on the spring constant of the spring.
Persons of ordinary skill in the art will appreciate that the present invention can be configured to be operated by either compressive or tensile force. Similarly, persons of ordinary skill in the art will appreciate that the present invention may be configured to be initially open or closed. Persons of ordinary skill in the art will also appreciate that a plurality of the present inventions may be employed in a single production string. When a plurality of the present inventions are located in a single production string, one method for making a plurality of the present inventions independently operable is to change the spring constant of spring 106 in each of the present inventions. If the spring constants are different in a plurality of split ball valves 100 in a single production string, different amounts of compressive or tensile force will operate specific split ball valves 100 within the production string. Thus, by changing the spring constant a person of ordinary skill in the art can operate each of the present inventions independently.
Persons of ordinary skill in the art will also appreciate that one or more of split ball valves 100 can be configured with a catch mechanism to keep the split ball valve open or closed in the absence of an actuating force. Generally, such catch mechanisms require an initial actuating force to open split ball valve 100. When sufficient force is applied to split ball valve 100, the catch engages and split ball vale 100 will remain open when the force on split ball valve 100 is released. A subsequent force, slightly larger than the actuating force required to set the catch, is required to release the catch and return valve doors 118 to the original closed position.
In some situations, a drilling engineer will find it necessary to run a second, concentric production string or a drill string inside of the existing production string. This procedure is well known in the art. A drilling engineer may also need to run a sucker rod down the center of the production string. In either case, a cylindrical string of drill pipe, casing, tubing, or rods is positioned in the center of the existing production string. The positioning of the second string of drill pipe, casing, tubing, or rods renders prior art valves, particularly prior art ball valves, inoperable. A second string of drill pipe, casing, tubing, or rods renders prior art ball valves inoperable because the second string of drill pipe, casing, tubing, or rods does not allow the ball to rotate from the open position into the closed position.
With respect to the above description, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function, manner of operation, assembly, and use are deemed readily apparent and obvious to one of ordinary skill in the art. The present invention encompasses all equivalent relationships to those illustrated in the drawings and described in the specification. The novel spirit of the present invention is still embodied by reordering or deleting some of the steps contained in this disclosure. The spirit of the invention is not meant to be limited in any way except by proper construction of the following claims.
Claims
1. A valve assembly comprising:
- an upper valve assembly;
- a lower valve assembly located adjacent to the upper valve assembly;
- a plurality of valve doors located in the lower valve assembly; and
- wherein the valve doors are rotated by exerting a compressive force on the valve assembly.
2. The valve assembly of claim 1 wherein the rotation opens the valve doors.
3. The valve assembly of claim 1 wherein the rotation closes the valve doors.
4. The valve assembly of claim 1 wherein the flow of a fluid through the valve assembly is stopped when the valve doors are closed.
5. The valve assembly of claim 1 wherein the valve assembly is fully ported when the valve doors are open.
6. The valve assembly of claim 1 wherein the upper valve assembly comprises:
- an upper housing;
- an upper collar located adjacent to the upper housing;
- a longitudinal support located adjacent to the upper collar; and
- a lower collar located adjacent to the longitudinal support.
7. The valve assembly of claim 6 wherein the longitudinal support comprises a rack; and
- wherein the rack intermeshes with a pinion gear to rotate the valve doors.
8. The valve assembly of claim 1 wherein the lower valve assembly comprises:
- a lower housing;
- a valve body located adjacent to the lower housing; and
- a pinion gear passing through the valve body.
9. The valve assembly of claim 8 wherein the valve body comprises a plurality of cavities; and wherein the valve doors recede into the cavities when the valve doors are opened.
10. The valve assembly of claim 8 wherein the pinion gear intermeshes with a rack to rotate the valve doors.
11. The valve assembly of claim 8 wherein the valve body comprises a valve upper body and a valve lower body.
12. The valve assembly of claim 8 wherein a key prevents slippage between the valve doors and the pinion gear.
13. The valve assembly of claim 1 wherein the valve doors comprise an aperture; and wherein the aperture allows the valve assembly to function when a string of drill pipe, casing, tubing, or rods passes through the valve assembly.
14. The valve assembly of claim 1 wherein a spring creates a separating force between the upper valve assembly and the lower valve assembly.
15. The valve assembly of claim 1 wherein the valve assembly is located down hole.
16. The valve assembly of claim 1 further comprising:
- a string of line pipe, casing, or tubing; and
- wherein the valve assembly is positioned inline with the string of line pipe, casing, or tubing.
17. The valve assembly of claim 16 further comprising: a drilling apparatus connected to the string of line pipe, casing, or tubing.
18. The valve assembly of claim 16 further comprising: a production apparatus connected to the string of line pipe, casing, or tubing.
19. A valve comprising:
- a valve assembly;
- a plurality of valve doors located in the valve assembly;
- an aperture located in the valve doors; and
- wherein the aperture allows the valve assembly to function when a string of drill pipe, casing, tubing, or rods passes through the valve assembly.
20. The valve of claim 19 wherein the valve doors are rotated by exerting a compressive force on the valve assembly.
21. The valve of claim 20 wherein the rotation opens the valve doors.
22. The valve of claim 20 wherein the rotation closes the valve doors.
23. The valve of claim 19 wherein the flow of a fluid through the valve assembly is stopped when the valve doors are closed.
24. The valve of claim 19 wherein the valve assembly is fully ported when the valve doors are open.
25. The valve of claim 19 valve wherein the valve assembly comprises:
- an upper housing;
- an upper collar located adjacent to the upper housing;
- a longitudinal support located adjacent to the upper collar; and
- a lower collar located adjacent to the longitudinal support.
26. The valve of claim 25 wherein the longitudinal support comprises a rack; and wherein the rack intermeshes with a pinion gear to rotate the valve doors.
27. The valve of claim 19 wherein the valve assembly comprises:
- a lower housing;
- a valve body located adjacent to the lower housing; and
- a pinion gear passing through the valve body.
28. The valve of claim 27 wherein the valve body comprises a plurality of cavities; and wherein the valve doors recede into the cavities when the valve doors are opened.
29. The valve of claim 27 wherein the pinion gear intermeshes with a rack to rotate the valve doors.
30. The valve of claim 27 wherein the valve body comprises a valve upper body and a valve lower body.
31. The valve of claim 27 wherein a key prevents slippage between the valve doors and the pinion gear.
32. The valve of claim 19 wherein a spring creates a separating force between an upper valve assembly and a lower valve assembly.
33. The valve of claim 19 wherein the valve assembly is located down hole.
34. The valve of claim 19 further comprising:
- a string of line pipe, casing, or tubing; and
- wherein the valve assembly is positioned inline with the string of line pipe, casing, or tubing.
35. The valve of claim 34 further comprising: a drilling apparatus connected to the string of line pipe, casing, or tubing.
36. The valve of claim 34 further comprising: a production apparatus connected to the string of line pipe, casing, or tubing.
37. An apparatus for stopping the flow of a fluid in a string of line pipe, casing, or tubing, the apparatus comprising:
- an upper valve assembly comprising: an upper housing; an upper collar located adjacent to the upper housing; a longitudinal support located adjacent to the upper collar; and a lower collar located adjacent to the longitudinal support;
- a lower valve assembly located adjacent to the upper valve assembly, the lower valve assembly comprising: a lower housing; a valve body located adjacent to the lower housing; a pinion gear passing through the valve body; and a plurality of valve doors located in the valve body;
- wherein the longitudinal support comprises a rack; and
- wherein the rack intermeshes with the pinion gear to rotate the valve doors.
38. The apparatus of claim 37 wherein the valve doors are rotated by exerting a compressive force on the upper valve assembly.
39. The apparatus of claim 38 wherein the rotation opens the valve doors.
40. The apparatus of claim 38 wherein the rotation closes the valve doors.
41. The apparatus of claim 37 wherein the flow of a fluid through the valve assembly is stopped when the valve doors are closed.
42. The apparatus of claim 37 wherein the apparatus is fully ported when the valve doors are open.
43. The apparatus of claim 37 wherein the valve body comprises a plurality of cavities; and wherein the valve doors recede into the cavities when the valve doors are opened.
44. The apparatus of claim 37 wherein the valve body comprises a valve upper body and a valve lower body.
45. The apparatus of claim 37 wherein a key prevents slippage between the valve doors and the pinion gear.
46. The apparatus of claim 37 wherein the valve doors comprise an aperture; and wherein the aperture allows the valve assembly to function when a string of drill pipe, casing, tubing, or rods passes through the valve assembly.
47. The apparatus of claim 37 wherein a spring creates a separating force between the upper valve assembly and the lower valve assembly.
48. The apparatus of claim 37 wherein the valve assembly is located down hole.
49. The apparatus of claim 37 wherein the valve assembly is positioned inline with the string of line pipe, casing, or tubing.
50. The apparatus of claim 37 further comprising: a drilling apparatus connected to the string of line pipe, casing, or tubing.
51. The apparatus of claim 37 further comprising: a production apparatus connected to the string of line pipe, casing, or tubing.
Type: Application
Filed: May 12, 2004
Publication Date: Nov 17, 2005
Inventors: William Hughes (Bixby, OK), Bjorn Eilertsen (Hundvaag)
Application Number: 10/844,172