This disclosure relates to an apparatus for shifting a valve. More specifically, but without limiting the scope of the disclosure, this disclosure relates to an apparatus and method for shifting a downhole valve from a first position to a second position, wherein the downhole valve is disposed within a well.
In the course of completing and producing hydrocarbon wells, operators find it necessary to install various components such as packers, gravel pack screens, liners, etc. As those of ordinary skill will readily recognize, one component used is a downhole valve, such as a sliding sleeve. The sliding sleeve valve generally has a sleeve member that is slidable from a first position to a second position, which generally corresponds to a closed position to an open position. Sliding sleeve valves are commercially available from Weatherford, Inc. under the name RIV.
Generally, prior art sliding sleeves use mechanical means to shift from the first position to the second position or from the second position to the first position. The shifting tools can be run into the well using a secondary work string such as wire line, tubing, and coiled tubing. The shifting tools provide a shifting force to manipulate a sleeve or mandrel in an assembly, such as an oil well completion tool. However, the use of the secondary work string poses many problems. For instance, the use of the secondary work string is expensive and time consuming. Also, the introduction of the secondary work string into the well may cause problems such as the secondary work string becoming stuck within the well.
Therefore, there is a need for an apparatus and method that will allow for an efficient shifting of a downhole valve. There is a also a need for an apparatus and method that dependably shifts a downhole valve without the need for a secondary string. Further, there is a need for a shifting device that is a separate component from the downhole valve. These needs, and many other needs, will be met by the apparatus and method herein disclosed.
A device for shifting a sliding sleeve from a first position to a second position is disclosed. The sliding sleeve is concentrically positioned within a well, and wherein the sliding sleeve contains a moveable inner member and wherein the well is in communication with a hydrocarbon reservoir. The device comprises an outer housing forming an annulus with the well and a power piston slidably disposed within the outer housing. The power piston comprises an upper shoulder configured to form an annular chamber and a tubular chamber relative to the outer housing, and a lower shoulder c configured to form an atmospheric chamber relative to the outer housing.
The device further comprises an up latch means for preventing upward movement of the power piston relative to the outer housing, a down latch means for preventing downward movement of the power piston relative to the outer housing, and wherein movement of the power piston shifts the moveable inner member from the first position to the second position. In one preferred embodiment, the down latch means comprises a shear ring insert, a first plurality of shear pins connecting the shear ring insert to the power piston, and a c-ring configured to prevent downward movement of the power piston after the first shear pins have sheared. Also, the up latch means may comprise a collet sleeve abutting the power piston, and wherein the collet sleeve includes a collet member engaging the outer housing, and an inner support member disposed within the collet member. The device may further contain a second plurality of shear pins for attaching the collet sleeve to the outer housing.
In the most preferred embodiment, the device includes an annular passage communicating the annulus to the annular chamber, and an inner bore passage communicating the inner bore to the tubular chamber. In one preferred embodiment, the valve is connected to a production screen, and wherein the production screen is placed adjacent a hydrocarbon reservoir in the well. Also, in one preferred embodiment, the outer housing is connected to a coiled tubing string, and wherein the coiled tubing string is placed concentrically within the well.
Also disclosed is a method of shifting a sliding sleeve valve from a first position to a second position, and wherein the sliding sleeve is positioned within a well. The method comprises providing an activating device operatively attached to the sliding sleeve valve, the activating device including: an outer housing forming an annulus with the well; a power piston disposed within the outer housing, and wherein the power piston includes an upper shoulder configured to form an annular chamber and a tubular chamber, and a lower shoulder configured to form an atmospheric chamber. The activating device further includes a collet member engaging the outer housing, an inner support member disposed within the collet member, a shear ring insert, and shear pins connecting the shear ring insert to the upper piston. In the preferred embodiment, the downhole valve contains a moveable inner member and wherein movement of the power piston shifts the moveable inner member from the first position to the second position.
The method further includes lowering the sliding sleeve valve and attached activating device into the well on a work string. The power piston is prevented from moving upward via the collet member, and additionally, the power piston is prevented from moving downward via a snap engaging the power piston. The method further includes performing a well intervention technique on the well.
The collet member is shifted upward. The method further comprises pressuring the tubular chamber of the activating device, shearing the shear pins that connected the shear ring insert to the power piston, and moving the power piston upward into engagement with the collet member. The method further includes disengaging the snap ring from the power piston so that the snap ring is allowed to slide along the power piston, capturing the snap ring within a groove on the power piston and releasing the applied pressure to the tubular chamber of the activating device. Next, the annular chamber is expanded relative to the atmospheric chamber thereby allowing the power piston to move downward, and the sliding sleeve valve is moved from the first position to the second position.
In the most preferred embodiment, the step of pressuring the internal bore includes applying pressure to an internal passage and into the tubular chamber and the step of expanding the annular chamber includes allowing an annulus pressure into an annular passage and into the annular chamber. Also, the step of moving the sliding sleeve valve from the first position to the second position includes abutting an end of the power piston against an end of the moveable inner member so that the power piston shifts the sliding sleeve valve from the first position to the second position. In one preferred embodiment, the sliding sleeve valve is run into the well on a coiled tubing string. Additionally, the step of performing the well intervention technique includes gravel packing the well.
An advantage of the present apparatus is that it insures full movement of the sliding sleeve to the open position. Another advantage is that most hydrocarbon well completion equipment that relies on hydraulic mechanisms has a hydraulic operator which cannot be separated from the main tool; the present apparatus is designed to be a separate component from the sliding sleeve valve.
Yet another advantage is that the present shifting apparatus is designed to replace wireline, tubing, and/or coiled tubing conveyed shifting tools that provide shifting force to manipulate a sleeve or mandrel in a hydrocarbon well completion tool. The present apparatus eliminates the need for a wireline, concentric string, or coil tubing operation to deliver the shifting force to the sliding sleeve.
A feature of the present invention includes the three (3) chambers that are configured to assist in delivering the force necessary to move the sleeve from a first position to a second position. The three chambers include the atmospheric, annular, and tubular chambers. Another feature includes a power piston that is operatively associated with the atomospheric, annular and tubular chamber. Yet another feature are the latching mechanisms that selectively latch the power piston in place. The latching mechanisms include use of a collet member, a shear ring insert and a snap ring member.
Referring collectively now to
The sliding sleeve valve 4 has an outer member 20 having ports 22 and a moveable inner member 24 containing slots 26, and wherein in a first position the slots 26 are isolated from the ports 22 and therefore there is no communication from the inner bore portion to the outer portion of the valve 4, and in a second position, the slots 26 are essentially aligned with the ports 22 which allows communication from the inner bore portion to the outer portion of the valve 4. Sliding sleeve valves are commercially available from Weatherford, Inc. under the name RIV. A sliding sleeve valve was disclosed in patent application Ser. No. 10/875,411, filed on 24 Jun. 2004, entitled “Valve Apparatus with Seal Assembly”, which is incorporated herein by express reference.
The shifting apparatus 2 has an internal bore, seen generally at 28, and slidably disposed within the bore 28 is the power piston 30. The power piston 30 has a first end 32 (seen generally in
Referring specifically to
The power piston 30 has configured thereon the lower push piston 96 which is another expanded section of the power piston 30, and wherein the lower push piston 96 contains the end shoulder 98.
The sleeve inner member 24 has the first end 106 and the second end 108. The second end 34 of the power piston 30 is configured for a gap with the first end 106 in order to move the sleeve inner member 24 from a first position to a second position, as will be more fully set out later in the description.
Referring now to
In
Referring now to
Changes and modifications in the specifically described embodiments can be carried out without departing from the scope of the invention which is intended to be limited only by the scope of the appended claims and any equivalents thereof.