Patent Application
20130186632
The present disclosure relates generally to subterranean operations, and, more particularly, the present disclosure relates to methods and apparatuses for wiping subterranean casings.
Subterranean operations typically include casings within a borehole. Fluids may be forced down the casing as part of drilling, treatment, and production operations, intended to either prepare the formation to produce a desired fluid, or maximize the desired fluid produced from the formation. In certain instances, a fluid forced down the casing, including cement, may leave residue on an interior surface of the casing. The residue may need to be removed to prevent it from contaminating other fluids and damaging other equipment located downhole. In certain instances, wipers are placed within the casing string to wipe the interior surface of the casing. Unfortunately, wiping the interior surface of the casing can be problematic, given that the casing may include different interior diameters and obstructions, including baffles and bends, that may cause a wiper to get stuck.
Some specific exemplary embodiments of the disclosure may be understood by referring, in part, to the following description and the accompanying drawings.
a illustrates a cross section of an example wiper object, according to aspects of the present disclosure.
b illustrates a cross section of an example wiper object, according to aspects of the present disclosure.
a illustrates an example wiper object wiping a subterranean casing, according to aspects of the present disclosure.
b illustrates an example wiper object wiping a subterranean casing, according to aspects of the present disclosure.
c illustrates and example wiper object wiping a subterranean casing, according to aspects of the present disclosure.
While embodiments of this disclosure have been depicted and described and are defined by reference to exemplary embodiments of the disclosure, such references do not imply a limitation on the disclosure, and no such limitation is to be inferred. The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to those skilled in the pertinent art and having the benefit of this disclosure. The depicted and described embodiments of this disclosure are examples only, and not exhaustive of the scope of the disclosure.
The present disclosure relates generally to subterranean operations, and, more particularly, the present disclosure relates to methods and apparatuses for wiping subterranean casings.
Illustrative embodiments of the present disclosure are described in detail herein. In the interest of clarity, not all features of an actual implementation may be described in this specification. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the specific implementation goals, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of the present disclosure.
To facilitate a better understanding of the present disclosure, the following examples of certain embodiments are given. In no way should the following examples be read to limit, or define, the scope of the disclosure. Embodiments of the present disclosure may be applicable to horizontal, vertical, deviated, or otherwise nonlinear wellbores in any type of subterranean formation. Embodiments may be applicable to injection wells as well as production wells, including hydrocarbon wells.
a and 1b show a cross section of an example wiper object 100, or wiper ball 100, according to aspects of the present disclosure. As can be seen, the wiper object 100 includes a spherical or ball shape. Although the wiper object 100 may be shown with the spherical of ball shape, other shapes are possible, as would be appreciated by one of ordinary skill in view of this disclosure. The wiper object 100 may comprise an inner core 104 with a width 104a. In the embodiment shown in
A deformable layer 102 with an uncompressed width 102a may surround the inner core 104, concentric with the inner core 104. In the embodiment shown, the deformable layer 104 includes a spherical shape, and the width 102a comprises a diameter of the deformable layer, but a spherical shape is not required. Other shapes are possible, as would be appreciated by one of ordinary skill in view of this disclosure. The uncompressed width 102a may be larger than or equal to a largest inner diameter of a subterranean casing, as will be described below. In certain embodiments, the deformable layer may be composed of an elastomeric foam, including, but not limited to, open-cell foams consisting of natural rubber, nitrile rubber, styrene butadiene rubbers, and polyurethane. The deformable layer may also me composed of a gel material. Although certain example compositions are stated above with respect to deformable layer 102 and inner core 104, one of ordinary skill in the art in view of this disclosure will appreciate the appropriate material for both the deformable layer 102 and inner core 104 given the requirements of a particular application.
In certain embodiments, a wiper object, such as the wiper object 100 in
An example subterranean string, casing string 206, with example sleeves 208 and 212, is shown in
In
As will be shown in
Once a wiper object, such as wiper object 200, is disposed within a subterranean casing, such as casing string 206, the wiper object may be forced away from the surface by, for example, pumping a fluid behind the wiper object. In
b shows the wiper object 200 passing through the baffle 210. As the wiper object 200 passes through the baffle 210, the deformable layer 202 deforms and compresses. The inner core 204 may pass through the baffle 210 because the width of the inner core 204 is less than the diameter 210a of the baffle 210. Advantageously, the spherical shape of the inner core 204 may reduce the likelihood of the wiper object 200 becoming lodged at the baffle 210 because the inner core 204 does not include edges which may catch on the baffle 210. Additionally, the spherical shape of the inner core 204, and the sizing of the inner core relative to the baffle 210 may decrease the pressure required to force the wiper object 200 through the baffle 210.
Once the wiper object 200 has passed through the baffle 210, the deformable layer 202 may re-expand to contact the inner surface of the casing string 206. The deformable layer 202 of the wiper object 200 may remain in contact with the inner surface of the casing string 206 until it encounters sleeve 212 and baffle 214. The deformable layer 202 may then deform as the wiper object 200 and inner core 204 pass through the baffle 214 in a similar manner to that shown with respect to baffle 210.
After the wiper object 200 has passed through the baffle 214, the deformable layer 202 may again re-expand to contact the inner surface of the casing string 206 as the wiper object 200 is forced towards the landing profile 216 as a distal end of the casing string. Once the wiper object 200 clears the baffle 214, the fluid forcing the wiper object downward may cause wiper object 200 to sealingly engage with the landing profile 216. As can be seen in
In certain embodiments, once the wiper object 200 has landed on the landing profile the internal pressure within the casing string 206 may be increased to open sleeve 208 and 212. In such instances, the inner core 204 of the wiper object 200 may need to withstand the increased pressure without deforming, as the seal with the landing profile may be broken if the inner core 204 deforms. For example, in certain embodiments, the inner core 204 may need to withstand 2500 psi of pressure without deforming. The pressure rating for the inner core 204 may change depending on the application, however, and one of ordinary skill in the art in view of this disclosure will appreciate the composition of the inner core 204 required to withstand the pressure rating.
Therefore, the present disclosure is well adapted to attain the ends and advantages mentioned as well as those that are inherent therein. The particular embodiments disclosed above are illustrative only, as the present disclosure may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular illustrative embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the present disclosure. Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee. 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.
