FLAPPER VALVE AND METHOD
A flapper valve with magnetic field hold open arrangement including a housing; a flapper pivotally mounted to the housing; and a magnet housing slidably mounted to the housing such that a magnetic field generating configuration of the magnet housing is movable between a position where it is capable of holding the flapper in an open position and where it is incapable of holding the flapper in an open position. A method for holding open a flapper of a flapper valve.
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In the downhole drilling and completion industry flapper valves have been used for an extended period of time. Such devices are useful whenever it is necessary to cause a fluid to move into the downhole environment from a remote location such as a surface location. Flapper valves come in a number of forms but not uncommonly are configured as tubing retrievable injection valves (TRIV), for example. Such valves often comprise a flapper that articulates and a flow tube that translates through a position occupied by the flapper when closed, thereby maintaining the flapper in an open position throughout the injection cycle. The open position is so maintained by the flow tube structurally pushing the flapper out of the way (causing rotation about its pivot) when the flapper valve is in the open position. While such flapper valves work well for their intended purposes, improvement is always desirable whether that improvement be in performance, cost reduction or both.
SUMMARYA flapper valve with magnetic field hold open arrangement including a housing; a flapper pivotally mounted to the housing; and a magnet housing slidably mounted to the housing such that a magnetic field generating configuration of the magnet housing is movable between a position where it is capable of holding the flapper in an open position and where it is incapable of holding the flapper in an open position.
A method for holding open a flapper of a flapper valve including pumping an injection fluid through the valve with magnetic field hold open arrangement including a housing; a flapper pivotally mounted to the housing; and a magnet housing slidably mounted to the housing such that a magnetic field generating configuration of the magnet housing is movable between a position where it is capable of holding the flapper in an open position and where it is incapable of holding the flapper in an open position; fording the flapper to an open position; coupling the magnet housing by fluid friction to the flowing injection fluid; urging the magnet housing downstream whereby the magnetic field generating component is in the position to hold the flapper in the open position; and magnetically holding the flapper in the open position.
A flapper valve with hold open arrangement including a flapper movable between an open condition and a closed condition; and a magnetic field generating component movable relative to the flapper to be in a position where the component is capable of magnetically holding the flapper in the open condition and a position where the component is incapable of holding the flapper in the open condition.
Referring now to the drawings wherein like elements are numbered alike in the several Figures:
Referring to
The flapper 16 itself comprises an erosion resistance that is either surface concentrated such as in the form of a coating or a surface layer or may be erosion resistant for a greater percentage of the flapper 16, including but not limited to the entire flapper being composed of erosion resistant material. This configuration allows the use of the valve 10 with high injection flow rates without a flow tube 12 being long enough to cover the flapper 16.
Because the flapper is exposed to flow during use of the valve 10 due to a short flow tube, fluid dynamics considerations are of importance when they are traditionally irrelevant to the flapper. The fluid flowing past and in contact with the flapper 16 causes turbulence behind the flapper 16 adjacent an inside surface 24 of a tubular 26 in which the valve 10 is installed. The turbulence can cause the flapper to move into the flow stream and not stay against the surface 24. This is a hindrance to injection and hence is to be avoided. The problem is exacerbated by higher injection rates. In order to address this issue the inventor hereof has determined that the effect of turbulence with respect to its ability to move the flapper into the injection flow can be minimized by reducing the fluid volume between a surface 28 of the flapper 16 and the surface 24. It is to be noted that the surface 28 may be of the flapper itself or may be of a material attached to the flapper. In one embodiment, the surface 28 is formed by providing a conformable material 30 attached to the flapper 16. The conformable material 30 will assume the shape of the inside surface 24 upon contact therewith and prevent any significant turbulent fluid from urging the flapper 16 away from the surface 24 during injection. This embodiment allows for irregularities in the surface 24 to be accounted for without knowing what those irregularities might be. More specifically, the tubing string in which the valve 10 is installed may have experienced flow cutting or erosion or may have become deformed during run in and resultingly does not necessarily present a cylindrical geometry at the surface 24 for a preconceived surface 28 to geometrically mate with. In such situation a conformable material 30 provides a wider range of functional success in reducing any potential volumes within which turbulent fluids might otherwise act. Conformable materials include but are not limited to rubber, nitrile, foams (including shape memory foam), etc. In other embodiments, the material may be a nonconformable material attached to the flapper or may be the flapper itself. In such cases, the material may geometrically mate well with the inside surface 24 and perform substantially as does the conformable material or may geometrically mate less well with the surface 24 but in any event, the material 30 will be formed to substantially geometrically mate with the surface 24 and accordingly will substantially displace turbulent fluid from the volume defined between the surface 28 and the surface 24. Due to the reduction in turbulent fluid in this location, impetus on the flapper 16 to move into the flow path of the injection fluid is reduced or eliminated.
Still referring to
In addition to the foregoing, and referring to
Referring to
In operation, a fluid 138 is applied in the direction of flow arrow 140 toward the flapper valve 100. The fluid 138 forces the flapper to swing open (position depicted in
In other embodiments, it is noted that the magnetic field generating components need not be on both sides of the resulting attractive interface but rather one could simply be a magnetically responsive material such as a ferrous metal. A reduced attractive force would result but if the component used has a sufficiently potent field, it would still function as noted above. Sliding action would still be used to break the interface wither by moving a nonmagnetic material into proximity with the components while the magnetically responsive material is slidingly moved away or a configuration where a sliding movement would simply position the field generating component farther away from a responsive material such as by sliding one of the structural features described in a direction that allows a recess to be aligned with the filed generating component. In such an embodiment the recess would position a responsive material far enough away from the field generating component to reduce the attractive force to a magnitude less than a closing force supplied by the torsion spring.
While one or more embodiments have been shown and described, modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation.
Claims
1. A flapper valve with magnetic field hold open arrangement comprising:
- a housing;
- a flapper pivotally mounted to the housing; and
- a magnet housing slidably mounted to the housing such that a magnetic field generating configuration of the magnet housing is movable between a position where it is capable of holding the flapper in an open position and where it is incapable of holding the flapper in an open position.
2. A flapper valve as claimed in claim 1 wherein the magnetic field generating configuration comprises a permanent magnet.
3. A flapper valve as claimed in claim 1 wherein the magnetic field generating configuration comprises an electromagnet.
4. A flapper valve as claimed in claim 1 further including a flapper sub fixedly attached to the housing.
5. A flapper valve as claimed in claim 4 wherein the flapper sub is fixedly connected to a flapper seat.
6. A flapper valve as claimed in claim 5 further including a tension spring extending between the flapper seat and a flow tube.
7. A flapper valve as claimed in claim 6 wherein the flow tube is biased by the tension spring to a position in which a seal disposed at the flapper seat is protected from fluid flow through the flow tube.
8. A flapper valve as claimed in claim 1 wherein the magnet housing is biased to a flapper closed position by a compression spring disposed between the housing and the magnet housing.
9. A flapper valve as claimed in claim 1 wherein the magnet housing is movable by fluid friction.
10. A flapper valve as claimed in claim 1 wherein the flapper includes a magnetic field generating component.
11. A flapper valve as claimed in claim 10 wherein the magnetic field generating component comprises a permanent magnet.
12. A flapper valve as claimed in claim 10 wherein the magnetic field generating component comprises an electromagnet.
13. A flapper valve as claimed in claim 10 wherein the magnetic field generating component is configured to produce a pole opposite a pole of the magnetic field generating component in the magnet housing.
14. A method for holding open a flapper of a flapper valve comprising:
- pumping an injection fluid through the valve as claimed in claim 1;
- fording the flapper to an open position;
- coupling the magnet housing by fluid friction to the flowing injection fluid;
- urging the magnet housing downstream whereby the magnetic field generating component is in the position to hold the flapper in the open position; and
- magnetically holding the flapper in the open position.
15. A flapper valve with hold open arrangement comprising;
- a flapper movable between an open condition and a closed condition; and
- a magnetic field generating component movable relative to the flapper to be in a position where the component is capable of magnetically holding the flapper in the open condition and a position where the component is incapable of holding the flapper in the open condition.
16. A flapper valve as claimed in claim 15 wherein the flapper further includes a magnetic field generating component.
17. A flapper valve as claimed in claim 15 wherein the magnetic field generating component comprises a permanent magnet.
18. A flapper valve as claimed in claim 15 wherein the magnetic field generating component comprises an electromagnet.
Type: Application
Filed: Oct 15, 2009
Publication Date: Apr 21, 2011
Applicant: BAKER HUGHES INCORPORATED (Houston, TX)
Inventor: Yang Xu (Houston, TX)
Application Number: 12/579,962