Patent Application
20240254854
Packers equipped with a tubing bridge plug have provided functionality to seal a cased borehole in the case of a leak from tubing into the annulus between the tubing and the casing. Alternatively, cementing of the borehole can provide such functionality. However, with either of these solutions, it is difficult to reopen the well for production after sealing.
This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.
In general, in one aspect, embodiments are related to methods for an extra shallow depth packer to avoid isolating the reservoir with cement. The methods include installing a shallow packer element in a well; supplying hydraulic oil to the shallow packer element; pressure testing the shallow packer element; monitoring a tubing casing annulus (TCA) for leaks; and inflating the shallow packer element upon detecting a leak in the TCA.
In general, in one aspect, embodiments are related to systems configured for an extra shallow depth packer to avoid isolating the reservoir with cement. The systems include casing installed within a borehole; tubing installed within the casing, wherein the tubing has a smaller diameter than the casing such that an area between the casing and the tubing forms a tubing casing annulus (TCA); a shallow packer element configured to be inserted into the casing within the TCA; a control line for providing hydraulic oil to the shallow packer element to inflate/deflate the shallow packer element; and a pressure sensor for detecting a pressure of the shallow packer element, wherein hydraulic oil is provided to the shallow packer element based on the pressure detected by the pressure sensor.
Other aspects and advantages of the claimed subject matter will be apparent from the following description and the appended claims.
In the following detailed description of embodiments of the disclosure, numerous specific details are set forth in order to provide a more thorough understanding of the disclosure. However, it will be apparent to one of ordinary skill in the art that the disclosure may be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid unnecessarily complicating the description.
Throughout the application, ordinal numbers (e.g., first, second, third, etc.) may be used as an adjective for an element (i.e., any noun in the application). The use of ordinal numbers is not to imply or create any particular ordering of the elements nor to limit any element to being only a single element unless expressly disclosed, such as using the terms “before”, “after”, “single”, and other such terminology. Rather, the use of ordinal numbers is to distinguish between the elements. By way of an example, a first element is distinct from a second element, and the first element may encompass more than one element and succeed (or precede) the second element in an ordering of elements.
In the following description of
In one aspect, embodiments disclosed herein relate to sealing a well so that fluids caused by a leak in the tubing do not reach the surface. In accordance with one or more embodiments, methods and systems are disclosed that protect the surface from a leak of hydrocarbon emulsion in the case that there is fluid communication between the tubing and the annulus. However, in one or more embodiments, such protection can be achieved without isolating the reservoir with cement.
To produce hydrocarbons, a portion of the casing (124) adjacent to a hydrocarbon bearing reservoir must be perforated to allow the flow of the hydrocarbons into the tubing (126). In order to control the high pressures of hydrocarbon inflows, a packer (122) is installed, which blocks any flow of fluid into and through the annulus. Multiple packers (122) may be installed in a single well (102), thus isolating and simultaneously producing from multiple hydrocarbon reservoirs. A plug is another option for isolating a portion of the well (102) for purposes that include blocking the flow of fluid into or out of that portion. A plug is essentially a packer (122) that does not allow tubing (126) and associated fluid flow through its center. However, a plug is sometimes not feasible to use in a highly deviated well (102).
A third method to limit the flow of fluids in a well (102) is cementation. This operates by squeezing cement through coiled tubing unit into the cased well (102). However, cementation is usually used as part of the completion process to permanently seal off a well (102). It is costly to perform, and restarting flow after cementing is labor and capital intensive. Packers (122), therefore, are the preferred choice for controlling fluids and fluid pressures, and allowing flow through tubing (126) to the surface.
Prior to commencing workover operations in a well (102), the TCA (128) must be pressure tested to ensure there is no leak in the packer (122) or fluid communication between the tubing (126) and the TCA (128). If the pressure test for the TCA (128) fails, the reservoir must be isolated with cement or, if the leak occurs at a shallow depth, the wellhead must be frozen. Both options can be costly and dangerous.
Pressure tests require taking pressure measurements of fluids in a reservoir and, for the purposes of the invention presented here, are used to determine the limits of equipment installed in the reservoir (e.g., packers and plugs). Data obtained from pressure tests may indicate how the formation and the equipment will react to pressure increases and decreases. During a pressure test, fluid may be injected into the well to see whether the packer or plug can resist the pressure increase. This technique is conducted upon completion of a well. Water is pumped into the well at a constant rate until a stable pressure is reached, at which point the pump is turned off and the rate at which pressure decreases is measured.
For the purposes of testing the shallow packer element, a buildup test is also possible. This is where a producing well (102) is shut in and the natural pressure from a producing formation will increase the pressure in the borehole until it reaches a state in which bottomhole pressure rises smoothly and is easily measured.
For either test, flow in the annulus indicates failure of the shallow packer element. Having a borehole sensor in the TCA is also useful for measuring decreases in pressure that may indicate a leak. Borehole sensors are mechanical or electronic devices that are capable of measuring borehole pressure, as well as fluid flow rate, temperature, vibration, and fluid composition. These devices can be installed permanently or temporarily.
In Step 451, the results of the pressure test determine whether or not the shallow packer element (200) can hold a constant pressure in the interval where the shallow packer element (200) is installed. If the shallow packer element (200) fails to hold under pressure, the workflow moves to Step 453, and the wellhead must be frozen or the well (102) must be cemented. If, in Step 451, the pressure test is successful, the workflow moves to Step 456, and the TCA (128) is monitored for leaks in the tubing (126) that allow fluid into the TCA (128).
In Step 458, the TCA (128) is checked for a leak. If no leak is detected, the workflow return to Step 456, and monitoring continues. If a leak is detected, the workflow moves to Step 460, and the shallow packer element (200) is inflated to contain the leak and prevent fluids from rising to the surface (116) through the TCA (128).
Although only a few example embodiments have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the example embodiments without materially departing from this invention. Accordingly, all such modifications are intended to be included within the scope of this disclosure as defined in the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures. Thus, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, whereas a screw employs a helical surface, in the environment of fastening wooden parts, a nail and a screw may be equivalent structures. It is the express intention of the applicant not to invoke 35 U.S.C. § 112(f) for any limitations of any of the claims herein, except for those in which the claim expressly uses the words ‘means for’ together with an associated function.
