Patent Application
20220049590
Not Applicable.
Not Applicable.
Technical Field: The disclosure relates to the field of plug and perforate processes in the petrochemical industry, in particular, devices and methods relating to the release or delivery of a frac ball or other occluding object onto a seat of a frac plug, after setting the frac plug into place.
In conventionally known plug and perforate systems, a bottom hole assembly (also referred to herein as “BHA”) may include one or more perforating guns, a plug setting tool, and a frac plug or isolation device. Some BHAs may optionally further include a ball release tool. The BHA delivers and sets a frac plug or isolation device at a desired location within the casing. The frac plug or isolation device typically has a throughbore which may be blocked or plugged with a frac ball or other object. A first known conventional means of delivering the frac ball include setting the frac plug, then firing the guns to perforate the well, and then dropping the frac ball through the casing and delivering the frac ball to the ball seat on the frac plug. This method of conveying the ball requires valuable time, fuel and fluid, which results in a relatively large environmental footprint. A second known conventional means of delivering the frac ball includes simultaneously carrying the frac ball and frac plug to the desired location, which is a comparatively smaller environmental footprint compared to the first known conventional means but is problematic when the perforating guns have misfired and the frac ball has nonetheless been inserted into the seat of the frac plug. In this scenario, the seating of the frac ball in the frac plug prevents the wireline from easily or efficiently running replacement guns. Effective or desired pumping is inhibited with the frac ball set into the seat of the frac plug if the guns are misfiring. To resume normal oilfield operations, a handful of processes may be used to unseat the frac ball or object from the frac plug seat and redeliver the BHA to the desired position. All of these corrective measures are generally expensive in terms of cost, operational delay and/or needed equipment and resources. US Patent Publication No. 20150252643, which is herein incorporated by reference in its entirety, proposes a device and method of automatic release of the frac ball upon the successful firing of at least one perforating gun, wherein the pressure released from the fired gun causes the release of the frac ball. However, the devices and methods under US20150252643 do not allow for precise operator control of when the frac ball is released. By way of example, the firing of any one gun may generate sufficient pressure for the frac ball to automatically release and engage the frac plug. In essence the frac ball may be automatically released regardless of whether the gun(s) fire correctly or misfire. The firing of less than all of the perforating guns may not be sufficient to proceed with additional fracturing activities, despite the automatic release of the frac ball. Thus, it may still be necessary to run replacement guns into the casing, but because the frac ball automatically seated onto the frac plug, this presents the same or similar problems as identified before. Additionally, the technology involved in perforating the casing is continually changing, including charge shaping, penetration depth and amount of explosive charge. When the amount of explosive charge is reduced but the penetration depth is the unchanged, these conventional methods may result in increased risk of failure of rupturing the fluid pathways. Hence mitigation would be required, and downhole mitigation takes up valuable rig time. Thus, a need exists for an improved device and method for a running tool and controlled frac ball release.
The disclosure relates to a method for deploying a frac ball within a subterranean location, having the steps of: deploying a wireline tool into the subterranean location, wherein the wireline tool defines a cavity housing the frac ball; pumping a fluid into the subterranean location; retaining the frac ball in the cavity while the fluid is pumped below a predetermined flow rate; setting a frac plug into the subterranean location; and firing one or more guns into the subterranean location.
As used herein, the terms “frac” or “frack” also includes encompasses the terms “fracture”, “fracturing”, “fracking”, “fracing”, or fraccing or “hydraulic fracturing” as commonly understood in the petrochemical field.
The exemplary embodiments may be better understood, and numerous objects, features, and advantages made apparent to those skilled in the art by referencing the accompanying drawings. These drawings are used to illustrate only exemplary embodiments and are not to be considered limiting of its scope, for the disclosure may admit to other equally effective exemplary embodiments. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness.
The description that follows includes exemplary apparatus, methods, techniques, and instruction sequences that embody techniques of the inventive subject matter. However, it is understood that the described embodiments may be practiced without these specific details.
The running tool 10 includes an outer sleeve 13 and an inner mandrel 20. In
Referring at least to
In a first orientation or position 10a (see e.g.
The inner mandrel 20 and frac plug 50 may each define a series of shear pin openings 31 and 55, respectively. Shear pin openings 31 may be defined towards the second or downhole end 22 of the inner mandrel 20, in the widened portion 29 of the cavity 27. The shear pin openings 31 may allow for the fixture of the frac plug 50 and compression of the components of BHA 60 through the use or activation of shear pins or shear screws 56. Shear pin openings 55 may be defined towards the first or uphole end 51 and on the outer surface of the frac plug 50. Shear pins 56 may be inserted into shear pin openings 31 and shear pin openings 55 when same are aligned. The shear pins 56 may retain or secure the frac plug 50 into place within the cavity 27 while the BHA 60 is in the process of delivering the frac plug 50 to the desired location. The shear pins 56 are configured to break or shear when sufficient predetermined or preset force is applied to the inner mandrel 20 and outer sleeve 13.
The inner mandrel 20 further includes a number or a set of retention devices, springs or levers 40. As depicted in the figures, the springs 40 are attached to the exterior surface of the inner mandrel 20 on the frustoconical shoulder 24 and inserted into the cavity 27 through a spring opening 42 as defined on said shoulder 24. The springs 40 may be attached at a first end to the inner mandrel 20 via a fastener 41. The spring opening 42 should be large enough or wide enough to allow, by way of example only, at least a 20° angle deflection or flexibility of the flat spring 40 within the cavity 27. In an exemplary embodiment there may be three openings 26 and three springs 40 with the three openings 26 respectively generally aligned to direct flow pressure to the three springs 40. In further alternative exemplary embodiments, the spring 40 may instead be attached (via fasteners 41 or other means as known in the art) to the interior surface of the cavity 27, while allowing for the same or similar amount of angle of deflection in the spring 40. Other desired angles of deflection, thickness, material, length and strength in the spring 40 may be selected as desired by the operator of the system. An exemplary embodiment of the springs 40 and shear pin openings 31 as located on the inner mandrel 20 is depicted in
When assembled with the frack plug, frac plug, mandrel plug, or isolation device 50 for running said frac plug 50 to the desired location or destination, the free end or unattached end of the springs or retention devices 40 may be located or situated in between the ball 30 and the ball seat 54. The free or unattached end of the springs 40 may optionally feature a means of retention such as a tab, hook, curve or lip 43 which further supports, retains or cages the ball 30 before the ball 30 is released via a preset flow rate 81 from the pump 80. As depicted in at least
In a first position 10a of the deployment wireline tool 10, wherein the springs 40 are containing, retaining or securing the ball 30, (by way of example, as depicted in at least
Once the deployment wireline tool 10 is at the desired location within the wellbore 63 (or other subterranean environment or location 63) for the frac plug 50, the tool 10 of BHA 60, carrying the ball or occluding object 30 within the cavity 27, is manipulated and powered through the wireline 62 to apply a sufficient pulling force on the inner mandrel 20 and/or a sufficient pushing force on the outer sleeve 13. As a result, the shear pins 56 are broken or sheared, and the frac plug 50 separates from the inner mandrel 20 and sets or engages into the casing 61 (or other subterranean environment) at the desired location. Subsequently, the
The fluid 81, as delivered by pump 80, continues to flow through cavity 27 to the throughbore 57 of the frac plug or isolation device 50. The ball 30, after release from the springs 40, travels with the fluid 81 to land, set or engage on or with the ball seat 54 on the frac plug 50, as seen in
If one or more of the guns 70 misfire, or in the case of any other malfunction, or under any circumstance as desired by the operator of the system, so long as the fluid 81 has not been pumped to the wireline tool 10 at or above the predetermined flow rate, the BHA 60 having retained the frac ball 30 may be retrieved and a replacement redeployed to the desired location within the wellbore 63. Unlike the prior art or other conventionally known devices and methods, with the exemplary embodiments described herein, the operator may control or command the timing of the release of the frac ball 30 by directing, controlling or manipulating the flow of fluid 81 from the pump 80, preventing the ball 30 from inadvertently, accidentally, or prematurely releasing and blocking the flow of fluid into wellbore 63 and past the frac plug 50. Without a ball 30 blocking pressure or fluid flow in the wellbore 63/casing 61, the BHA 60 may be easily retrieved and redeployed using commonly known, inexpensive mitigation techniques and with relatively minor setback to the overall operation.
While the embodiments are described with reference to various implementations and exploitations, it will be understood that these embodiments are illustrative and that the scope of the inventive subject matter is not limited to them. Many variations, modifications, additions, and improvements are possible. By way of example only, although the deployment wireline tool 10 and BHA 60 are frequently depicted and described herein as within a casing 61 and or wellbore 64, it is to be appreciated that same or similar exemplary embodiments of the devices and processes disclosed within may be applied to any subterranean location or environment.
Plural instances may be provided for components, operations or structures described herein as a single instance. In general, structures and functionality presented as separate components in the exemplary configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements may fall within the scope of the inventive subject matter.
| Number | Date | Country | |
|---|---|---|---|
| 63066025 | Aug 2020 | US |
