None.
1. Technical Field
This invention relates to tools for recovering actuator elements, such as, balls and darts, inserted into wells from the surface to actuate subterranean well tools such as sliding sleeve valves and tools for shifting the well tools. More particularly, this invention relates to recovering actuator elements from sleeve valves and for shifting elements of the valves.
2. Background Art
It is common to assemble and install wellbores with a plurality of sleeve valves spaced along the length of the wellbore to provide access to selected formation areas along the wellbore. These sleeve valves are operated by inserting and pumping actuator elements down the wellbore. These balls engage a seat on the valve's sleeve allowing pressure to build up to force the ball and sleeve to shift to the open position. It is also common to use circular cross section shaped actuator darts instead of spherical balls. In the description herein, for simplicity the actuator elements will be referred to as actuator balls, but it is to be understood that the invention is applicable to recover actuator darts.
Typically when multiple valves are present in a well, balls and mating valve seats of different diameters were used. The valves were arranges with the smallest seat at the bottom of the well and with the largest valve seat nearest the well head. In these configurations the number of valves in a well was limited by the number of ball diameters that could be used. In addition, the smaller valve seats presented undesirable flow restrictions in the well during production. After theses balls are used to actuate the valves, they were either flowed back to the surface or drilled out.
New sleeve valve systems have been developed where multiple valves are actuated by balls of the same diameter. The valve seats, sometime called baffles, can be actuated by various means to change from an open-bore ball pass-through state to a restricted bore ball-catching state. The valves in these new valve systems are assembled with the bottom valve (farthest from the wellhead first) actuating to the ball-catching state first and then the valves progressing up the wellbore toward the well head actuating to the ball catching state in sequence. In these new systems, none of the actuator balls below except the top ball can be flowed back to the surface due to restricted wellbore in the valves above the actuator balls. Removal of the actuator balls requires expensive drilling procedures.
The present invention provide a down hole wellbore tool and method for attachment to wire line or tubing string to retrieve a plurality of actuator balls of the same size and for engaging and shifting elements of the valve.
The drawing is incorporated into and forms a part of the specification to illustrate at least one embodiment and example of the present invention. Together with the written description, the drawing serves to explain the principles of the invention. The drawing is only for the purpose of illustrating at least one preferred example of at least one embodiment of the invention and is not to be construed as limiting the invention to only the illustrated and described example or examples. The various advantages and features of the various embodiments of the present invention will be apparent from a consideration of the drawing in which:
The present invention provides an improved tool and method for retrieving actuator balls and engaging and shifting elements of the valves. The present invention's particular applicability is to multiple sleeve wellbores that are actuated by balls of the same diameter.
Referring more particularly to the drawings, wherein like reference characters are used throughout the various figures to refer to like or corresponding parts, there is shown in
The tool 10 has an elongated tubular body 12 of relatively rigid material with an actuator ball receiving cylindrical chamber 14 formed therein. The chamber is open at its down-hole end 16 to accommodate the entry of actuator balls into the chamber. Only a portion of the body 12 of tool 10 is illustrated, it being understood that the tool 10 is assembled in sections (not illustrated) extending from the up-hole end 18 such that the chamber 14 is of a sufficient axial length to retrieve and hold therein all of the plurality of actuator balls in a given wellbore. The up-hole end includes a wire line connection or threads (not illustrated) as is known in the art. In addition the internal diameter of the chamber is set to be of a size to receive the actuator balls therein.
An actuator section 20 of the body 14 is positioned adjacent the actuator ball receiving down-hole end 16. As will be described herein, section 20 is configured to engage a down-hole sleeve valve and change it to the open-bore state. Section 20 comprises a plurality of longitudinally extending sections 22 separated by slots 24. Sections 22 are slightly bowed radially outward and act as leaf springs which can be resiliently deflected radially inwardly. When the profiles 26 are forced to deflected inwardly sections 22 bend or deform inwardly and sections 22 will snap back when the force is released. Tool engaging profiles 26 are formed on the exterior surface of the sections 22. Each profile 26 includes a slot 28 with and upwardly facing shoulder 30 at its lower end and a ramp surface 32 at its upper end.
The down-hole end 16 comprises a rubber element 40 bonded or otherwise attached to the body 12. The rubber element 40 has a hook shaped reduced internal diameter portion 42. The rubber element 40 is of a size that when it is forced downward onto an actuator ball it will stretch over the actuator ball and retain it in the chamber 14. The tool 10 is designed to be lowered into a wellbore and when it encounters an actuator ball, it will swallow it into its belly like chamber 14. Indeed, the chamber is large enough that it can hold a plurality of actuator balls.
Turning now to
A sleeve valve 70 with seals 72 acts as a valve element and is mounted in the valve body to axially slide from a position blocking or closing off the ports 66 to a position axially spaced from the ports 66, as is illustrated in
A baffle 80 is located in the valve 60 axially below the sleeve valve 70. Baffle 80 is sleeve shape and is made of spring steel. One end of baffle 80 has slots 82 to form a collet that can radially contract from an expanded shape to form an annular ball catching seat 84. As illustrated in
The method of use of the tool 10 will be described with regard to the valve illustrated in
Once the valve moves to the ball catching state, an actuator ball can be dropped onto the seat and pressure in the well increased to move the sleeve 70 valve to the open position illustrated in
When well treatments are completed the tool 10 of the present invention can be used to retrieve the actuator balls and to return the valve 60 to the open bore state. Tool 10 is lowered into the well until the down-hole end 16 engages and captures the first actuator ball 90 in the chamber 14. The tool 10 is lifted with the hook shaped reduced internal diameter portion 42 of the rubber element 40 retaining the ball 90 in the chamber 14.
As the tool moves through each valve 60, the valve is changed to the open bore state with the valve sleeve 70 positioned spaced away from baffle 80. In this position the collet end of baffle 80 expands radially to create an open bore pathway through the valve 60.
To move the valve sleeve 70 to a position axially spaced away from the baffle, the tool is raised. The interior annular profile 74 formed on the interior surface of sleeve valve 70 engages the corresponding exterior profile 26 on tool 10. As the tool 10 raised the downward facing shoulder 76 on profile 74 contacts the upward facing shoulder 30 on tool 10 and axially forces the valve sleeve 70 to shift upward. As the tool 10 moves up the well the engaged shoulders will shift the sleeve upward until stopped by the engagement of shoulder 68 with face 79. With the sleeve shifted into contact with shoulder 68 the shape and/or size of the profiles 26 and 74 are selected to cause the exterior profile on the tool to deflect radially inward so that shoulders 76 and 30 to disengage. Thus, with the valve sleeve 70 contacting shoulder 68 and in a position out from under the baffle 80, the collet end of baffle 80 is released to expand radially to create the open bore state.
With the baffle in the open bore position the tool 10 can be lowered down into the well through the valve 60 to engage and capture the remaining actuator balls 90 in the well. The downward facing ramp surfaces on the tool 10 and upward facing ramp surfaces on sleeve valve 60 prevent downward shifting of the sleeve valve as the tool moves down through the valve. The tool 10 can be retrieved from the well through each valve.
The present inventions have been described by way of example by referring to a valve configuration wherein the sleeve is shifted upward to retract the baffle. It should be understood, that the present inventions are also applicable to valves wherein the sleeve is shifted downward to change the valve to the open bore state. In addition to changing the valve to the open bore state, the tool could be used to shift the baffle and shipt the valve between the open and closed positions.
While compositions and methods are described in terms of “comprising,” “containing,” or “including” various components or steps, the compositions and methods also can “consist essentially of” or “consist of” the various components and steps. As used herein, the words “comprise,” “have,” “include,” and all grammatical variations thereof are each intended to have an open, non-limiting meaning that does not exclude additional elements or steps.
Therefore, the present inventions are well adapted to carry out the objects and attain the ends and advantages mentioned as well as those which are inherent therein. While the invention has been depicted, described, and is defined by reference to exemplary embodiments of the inventions, such a reference does not imply a limitation on the inventions, and no such limitation is to be inferred. The inventions are capable of considerable modification, alteration, and equivalents in form and function, as will occur to those ordinarily skilled in the pertinent arts and having the benefit of this disclosure.
The depicted and described embodiments of the inventions are exemplary only, and are not exhaustive of the scope of the inventions. Consequently, the inventions are intended to be limited only by the spirit and scope of the appended claims, giving full cognizance to equivalents in all respects.
Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee. Moreover, the indefinite articles “a” or “an”, as used in the claims, are defined herein to mean one or more than one of the element that it introduces. If there is any conflict in the usages of a word or term in this specification and one or more patent(s) or other documents that may be incorporated herein by reference, the definitions that are consistent with this specification should be adopted.