DENSITY ACTUATABLE DOWNHOLE MEMBER AND METHODS
Disclosed herein is an actuatable downhole member. The actuatable downhole member includes, a downhole member with a selected density, the selected density being comparable to an anticipated downhole fluid density such that a difference in the density of the downhole member and the density of the downhole fluid creates a bias on the downhole member to actuate the downhole member.
Latest Baker Hughes Incorporated Patents:
Actuating downhole devices such as check valves, for example, often is accomplished by remote control via a slickline or wireline. Such actuation can include movement of a downhole member directly through movement of the wireline or can include communication to a downhole actuator such as an electric motor, for example, through the wireline. In either case the actuation is initiated remotely. Other systems have been developed that do not require remote actuation but instead rely on a downhole change in pressure to initiate an actuation. Such systems may use a pressurized cavity with a membrane set to rupture at a selected pressure, for example. Automated actuation of downhole tools is desirable and systems enabling automated actuation would be well received in the art.
BRIEF DESCRIPTION OF THE INVENTIONDisclosed herein is an actuatable downhole member. The actuatable downhole member includes, a downhole member with a selected density, the selected density being comparable to an anticipated downhole fluid density such that a difference in the density of the downhole member and the density of the downhole fluid creates a bias on the downhole member to actuate the downhole member.
Further disclosed herein is a method of malting a density actuatable downhole member. The method includes, determining a target density for the downhole member based on an estimated downhole fluid density and forming the downhole member such that it has the target density.
Further disclosed herein is a method of actuating a downhole member. The method includes, positioning the downhole member having a target density downhole where it is submergible in fluid and actuating the downhole member through buoyancy forces acting upon the downhole member in response to fluid at least partially submerging the downhole member.
The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:
A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.
Referring to
Forces to actuate the flapper 14 between the closed configuration 46 and the open configuration 50 can be generated by a difference in density between the flapper 14 and a fluid within which the flapper 14 is at least partially submerged. A description of the mechanics of such actuation will be presented below after embodiments of controlling density of the flapper 14 during fabrication thereof are discussed.
Referring to
An alternate embodiment can provide additional variation in density through controlling the number, size and shape of voids in the finished part without sacrificing mechanical properties. This embodiment includes using a metal powder 58 made up of hollow or foamed particles. As such the density of the finished part can have a greater density range than systems using solid particles. Alternately, the density can be controlled by use of particles other than metal, such as ceramic or glass, for example. Inadequate adhesion of particles to one another with such alternate materials, however, can weaken the finished part. An embodiment disclosed herein therefore, addresses this concern by coating or plating the nonmetallic particles prior to use in the powdered metallurgy process. One method of coating the particles is through chemical vapor deposition or CVD. The chemical vapor deposition process can controllably grow a coating of a specific metal onto surfaces of the powdered material particles. The metal coating can have excellent adhesion to the individual particles and provide an exterior surface on each particle, susceptible to adhesion, to other particles in the sintering process, thereby providing greater strength in the finished part. The use of nonmetallic powder material prior to the CVD process permits a greater range of density of the finished part, as well as allowing for control of other properties such as electrical conductivity, magnetic properties, coefficient of thermal expansion and thermal conductivity, for example.
Referring to
The foregoing embodiments could also be combined to create yet another embodiment by, for example, making the core 78 with a powdered metallurgical process with hollow, foamed or nonmetallic particles, the individual particles of which may or may not be coated as disclosed above. This powdered metal core 78 could then be coated, possibly with a CVD process, for example, to attain the target density of the finished part.
How the density of the flapper 14 effects actuation of the flapper 14 will be discussed here in more detail. Forces acting upon the flapper 14 can be proportional to the mass of the flapper 14. A few examples of such forces are gravitational force and forces due to acceleration such as centripetal force, for example. In addition to acting upon the flapper 14, these forces also act upon everything that has mass, including any fluid, that may be near or in contact with the flapper 14.
Additionally, if the flapper 14 is at least partially submerged in the fluid there will also be buoyancy forces acting upon the flapper 14 by the fluid. The buoyancy forces are proportional to the difference in density of the flapper 14 and the fluid for the portion of the flapper 14 that is submerged within the fluid. The buoyancy forces act in a direction opposite to that of the gravitational or centripetal forces. As such, changes in the buoyancy forces can be used to actuate the flapper 14. Changes in buoyancy forces can result from changes in either the density of fluid into which at least a portion of the flapper 14 is submerged or changes in the amount of the flapper 14 that is submerged in the fluid. As such, by selecting a density and actuation direction of the flapper 14 relative to the density of the fluid and direction of the forces acting thereupon, the flapper can be set to automatically actuate in response to changes in density and position of the fluid with respect to the flapper 14. Such automated control of a downhole system 10 may be desirable for multiple reasons including, faster response than an operator initiated system and system simplification with lower costs as compared to systems utilizing a communication link between surface and the downhole actuatable member.
While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims.
Claims
1. An actuatable downhole member comprising:
- a downhole member with a selected density, the selected density being comparable to an anticipated downhole fluid density such that a difference in the density of the downhole member and the density of the downhole fluid creates a bias on the downhole member to actuate the downhole member.
2. The actuatable downhole member of claim 1, wherein the downhole member is a valve.
3. The actuatable downhole member of claim 1, wherein the downhole member is a flapper.
4. The actuatable downhole member of claim 1, further comprising a core made of a first material and a coating made of a second material, the first material having a different density than the second material.
5. The actuatable downhole member of claim 4, wherein one of the first material and the second material is denser than the selected density and the other of the first material and the second material is less dense than the selected density.
6. The actuatable downhole member of claim 4, wherein the second material is bonded to the first material through chemical vapor deposition.
7. The actuatable downhole member of claim 1, wherein the downhole member is fabricated from a powdered material.
8. The actuatable downhole member of claim 7, wherein the powdered material is nonmetallic.
9. The actuatable downhole member of claim 7, wherein the powdered material is coated through chemical vapor deposition.
10. The actuatable downhole member of claim 7, wherein the powdered material is glass or ceramic.
11. The actuatable downhole member of claim 7, wherein the powdered material is hollow or foamed.
12. The actuatable downhole member of claim 1, wherein the downhole member is sintered.
13. A method of making a density actuatable downhole member comprising:
- determining a target density for the downhole member based on an estimated downhole fluid density; and
- forming the downhole member such that it has the target density.
14. The method of claim 13 further comprising:
- selecting at least one material with a density other than the target density;
- shaping the material to a near final shape of the downhole member; and
- processing the near final shape to a final shape having the target density.
15. The method of claim 14, wherein the shaping and processing include the process of powdered metallurgy.
16. The method of claim 13, further comprising:
- selecting a first material with a density other than the target density;
- selecting a second material with a density other than the target density; and
- adhering the first material to the second material.
17. The method of claim 16, wherein one of the first material and the second material is denser than the target density and the other of the first material and the second material that is not denser than the target density is less dense than the target density.
18. The method of claim 17, wherein the adhering further includes coating.
19. The method of claim 17, wherein the adhering further includes chemical vapor depositioning.
20. A method of actuating a downhole member comprising:
- positioning the downhole member having a target density downhole where it is submergible in fluid; and
- actuating the downhole member through buoyancy forces acting upon the downhole member in response to fluid at least partially submerging the downhole member.
Type: Application
Filed: Nov 1, 2007
Publication Date: May 7, 2009
Applicant: Baker Hughes Incorporated (Houston, TX)
Inventors: Kevin C. Holmes (Houston, TX), Michael H. Johnson (Katy, TX)
Application Number: 11/933,616
International Classification: E21B 34/00 (20060101); E21B 34/06 (20060101);