GAS LIFT BARRIER VALVE
A gas lift valve can include a degradable component; a valve; and a longitudinally extending tubular body that defines a flow path therein that includes the valve disposed between the degradable component and an opening of the tubular body.
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This application is a divisional of co-pending a U.S. patent application having Ser. No. 12/650,499, filed 30 Dec. 2009, which is incorporated by reference herein.
TECHNICAL FIELDThe present application relates to devices for injecting lift gas into a production conduit of an oil well via one or more gas lift flow control devices and to a gas lift flow control device for use in the method.
BACKGROUNDLift gas can be pumped into an annulus between a production tubing and surrounding well casing and subsequently into the production tubing from the annulus via one or more one way gas lift flow control devices in side pockets that are distributed along the length of the production tubing. The lift gas which is injected through the flow control devices into the crude oil (or other fluid) stream in the production conduit reduces the density of the fluid column in the production conduit and enhances the crude oil production rate of the well.
Gas lift flow control devices can use one way check valves which comprise a flapper type valve that presses against a seating. They can also include a ball or hemisphere or cone which is pressed against a valve seating ring by a spring. If the lift gas pressure is higher than the pressure of the crude oil stream in the production conduit then this pressure difference exceeds the forces exerted to the check valve by the spring so that the spring is compressed and the valve is opened and lift gas is permitted to flow from the gas filled injection conduit into the production conduit. If however the pressure of the crude oil stream is higher than the lift gas pressure in the injection conduit, the accumulated forces of the spring and the pressure difference across the gas lift flow control device closes the check valve and prevents crude oil, or other fluid, to flow from the production conduit into the injection conduit.
Issues exist relating to integrity of the sealing function of the one way valve, particularly across a wide range of pressure differentials, e.g., zero to high pressure differential. Also, issues exist with degradation of the seals through exposure to flow of gas and well fluids for various reasons, e.g., debris in the flow.
Accordingly, it is desirable to improve the sealing of the one way valve, and also to protect the integrity of the sealing components during flow of the gas and operation in general.
SUMMARYA preferred embodiment includes a gas lift valve that has a longitudinally extending tubular body having an inlet and an outlet, a flow path extending between the inlet and the outlet, and a flow tube located inside the body. The flow tube is translatable in the axial direction between at least a first and a second position. A venturi orifice is located inside the body along the flow path. A seal part is located proximate to the outlet of the body. A flapper is connected with the body by way of a hinge part and the flapper has at least a first open position and a second closed position. The closed position is where the flapper contacts the seal thereby closing the flowpath and the second closed position is where the flapper does not contact the seal and does not close the flowpath.
The following is a brief description of figures herein showing some preferred embodiments of various designs.
In the following description, numerous details are set forth to provide an understanding of the present embodiments. However, it will be understood by those skilled in the art that the present embodiments may be practiced without many of these details and that numerous variations or modifications from the described embodiments are possible.
As used here, the terms “above” and “below”; “up” and “down”; “upper” and “lower”; “upwardly” and “downwardly”; and other like terms indicating relative positions above or below a given point or element are used in this description to more clearly describe some embodiments. However, when applied to equipment and methods for use in wells that are deviated or horizontal, such terms may refer to a left to right, right to left, or diagonal relationship as appropriate.
A purpose of the flow tube 4 is to protect the seal part 2. According to embodiments, when in use the gas lift valve is located in a conduit connecting a well annulus with an internal production tube. The gas lift valve is located in a side pocket of the production tubing that connects the annulus with the interior of the production tubing. Gas is forced into the annulus and when a proper pressure is reached, the gas travels from the annulus, through the gas lift valve, and into the production tubing. As is apparent from
The seal part 2 can be made up of a hard metal portion 18 and at least one softer spring or elastomeric portion 19. Additionally, the seal part 2 can have a self aligning feature. In
In
The embodiments described herein are merely examples of various preferred designs and are not meant in any way to unduly limit the scope of any presently recited or subsequently related claims.
Claims
1. A gas lift valve, comprising:
- a degradable component;
- a valve; and
- a longitudinally extending tubular body that defines a flow path therein that comprises the valve disposed between the degradable component and an opening of the tubular body.
2. The gas lift valve of claim 1 wherein the degradable component comprises a degradable material.
3. The gas lift valve of claim 2 wherein the degradable material dissolves in a well environment.
4. The gas lift valve of claim 1 wherein the degradable component is connected to the tubular body.
5. The gas lift valve of claim 1 wherein the degradable component comprises a nose profile.
6. The gas lift valve of claim 5 wherein the nose profile comprises a shape that helps deployment and location of the gas lift valve in a pocket of production tubing.
7. The gas lift valve of claim 1 wherein the degradable component is pointed.
8. The gas lift valve of claim 1 wherein the degradable component is contoured.
9. The gas lift valve of claim 1 wherein the degradable component comprises a nose component connected to the tubular body wherein the nose component comprises a pointed profile.
10. The gas lift valve of claim 1 wherein the degradable component comprises a nose component connected to the tubular body wherein the nose component comprises a contoured profile.
11. A system comprising:
- production tubing that comprises a pocket; and
- a gas lift valve configured for receipt in the pocket wherein the gas lift valve comprises a degradable component, a valve, and a longitudinally extending tubular body that defines a flow path therein that comprises the valve disposed between the degradable component and an opening of the tubular body.
12. The system of claim 11 wherein the degradable component comprises a degradable material.
13. The system of claim 12 wherein the degradable material dissolves in a well environment.
14. The system of claim 11 wherein the degradable component is connected to the tubular body.
15. The system of claim 11 wherein the degradable component comprises a nose profile.
16. A method comprising:
- in production tubing disposed in a well that comprises well fluid wherein the production tubing comprises a pocket and a gas lift valve received by the pocket wherein the gas lift valve comprises a degradable component, a valve, and a longitudinally extending tubular body that defines a flow path therein that comprises the valve disposed between the degradable component and an opening of the tubular body, degrading the degradable component by exposure to the well fluid;
- responsive to a pressure differential, opening the valve; and
- flowing fluid via the flow path of the tubular body.
17. The method of claim 16 wherein the degrading creates an opening to the flow path.
18. The method of claim 16 wherein the degradable component comprises a nose component connected to the tubular body.
19. The method of claim 16 further comprising locating the gas lift valve in the pocket of the production tubing.
20. The method of claim 19 wherein the degradable component comprises a nose profile that facilitates the locating.
Type: Application
Filed: Jan 28, 2014
Publication Date: May 22, 2014
Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION (SUGAR LAND, TX)
Inventors: Kevin T. Scarsdale (Pearland, TX), Jason Kamphaus (Missouri City, TX), Jacob Hahn (Pearland, TX), Thomas M. White (Spring, TX)
Application Number: 14/165,755
International Classification: E21B 43/12 (20060101);