Patent Application
20250020056
This technical solution relates to the field of data transmission and parameter monitoring, in particular to a wireless system for monitoring downhole parameters. This solution is designed to create a two-way wireless communication channel and monitor the parameters in wells drilled through rocks and cased with metal tubes (e.g. wells for oil and gas production).
Traditionally, cable systems have been used to transmit information between downhole equipment and the wellhead. However, the use of such systems poses the risks of damaging the cable during installation and operation, which results in the loss of communication and requires costly repairs.
A method of transmitting information from a well through an electrical communication channel and apparatus for its implementation are known from RU2528771C2, published on Sep. 20, 2014. That method for transmitting information from a well via an electrical communication channel provides for exciting electric current in a string of metal tubes located in the well and separated into a top and a bottom parts by a dielectric insert, and recording a voltage change at the surface caused by the current pulsation in the tube. In this case, the useful signal is the change in voltage at the terminals of the receiving cylindrical coil and represents a function of the alternating current flowing in the tube excited by means of an alternating EMF applied to a dielectric insert. A disadvantage of this method for transmitting the information from the wells cased with metal tubes is the need to install a dielectric insert for electrical separation of the casing tube string, which can be done only at the construction of the well or during its workover.
A method of implementing an electromagnetic communication channel in the form of a tube-to-ground system is known from U.S. Pat. No. 7,114,561B2, published on Oct. 3, 2006. The main element of this communication system is an induction choke, which is located on the outside of the string (and mounted around the casing string before it is secured with cement). To protect against external damage, it is hardened with epoxy. A means is provided to electrically insulate the well elements from ground connection. This is achieved by using electrical isolators on the sub-surface gate valves. A major disadvantage of such system is the impossibility to repair and remove the device once the wellbore has been cemented, as well as the complexity of process operations to mount the transceiver on the casing string and run it into the well.
The claimed technical solution is aimed at solving the technical problem of monitoring and optimizing the operating modes of oil and gas wells. The monitoring and optimization of parameters are ensured by implementing downhole systems for operational monitoring of oil and gas well parameters. However, the widespread use of such systems is hampered by the process risks associated with running the data cable downhole. A wireless system for monitoring downhole parameters created to solve this problem uses the elements of the well structure, such as production string, tubing, and components of downhole pumping equipment hanger, to create a communication channel. The particular embodiments of the proposed solution are characterized in the dependent claims.
The technical result achieved by solving the above technical problem is the ability to monitor the well parameters by operating a wireless system for monitoring downhole parameters. An additional technical result is the implementation of the purpose.
The claimed technical result is achieved by implementing a wireless system for monitoring downhole parameters according to the first embodiment (wherein the walls of the well are cased with metal tube string), which comprises the following:
The claimed technical result is achieved by implementing a wireless system for monitoring downhole parameters according to the second embodiment (wherein the walls of the borehole are cased with metal tube string), which comprises the following:
In a particular embodiment for implementing the proposed system according to two embodiments, the grounding device is located from the casing string at a distance that enables to detect the potential difference between the grounding device and the casing string.
In a particular embodiment for implementing the proposed system according to two embodiments, the wellhead transceiver is enabled to transmit a signal by changing the potential of the casing string relative to the grounding device, wherein the change in potential begins to propagate along the entire length of the string and, after a time ‘t’, reaches the downhole transceiver arrangement, and the losses during signal transmission from the upper closing point (A) to the lower closing point (B) cause a potential difference between points A and B, which is detected by the receiver of the downhole instrument module.
In a particular embodiment for implementing the proposed system according to two embodiments, the downhole instrument module is enabled to transmit a signal by changing the potential of point A of the casing string relative to point B, wherein the change in potential begins to propagate along the entire length of the string and, after a time ‘t’, reaches the wellhead, and a potential difference, which occurs between the casing string and the grounding device, is detected by the wellhead transceiver.
In a particular embodiment for implementing the proposed system according to two embodiments, the contact element is installed at a distance of more than 5 meters to the edge of casing metal tubes.
A particular embodiment for implementing the proposed system according to the second embodiment is characterized in that the packer is electrically conductive and is enabled to provide electrical contact with the casing string.
The embodiment of the invention will be described below in accordance with the accompanying drawings, which are presented to explain the essence of the invention and in no way limit the scope of the invention. The following drawings are attached to the application:
The following detailed description of this invention embodiment provides numerous details of the embodiment to ensure a clear understanding of the present invention. However, to those skilled in the art, it will be obvious how the present invention could be used, whether with or without these details of its embodiment. In other cases, the well-known methods, procedures, and components have not been described in detail to avoid overcomplicating the understanding of this invention's features.
In addition, the above presentation will make it clear that the invention is not limited to the presented embodiment. Numerous possible modifications, changes, variations, and substitutions, that retain the essence and form of this invention, will be obvious to those skilled in the art.
The well walls are cased with metal tube string (casing string), which is secured with cement (cement ring (5)). The well can be drilled through the rocks (6) from the ground surface (wellhead) to the bottom hole (maximum available well depth). A string of casing tubes should have no electrical discontinuities along its entire length up to the wellhead.
According to the first embodiment (
According to the second embodiment (
A transceiver (14) mounted on the wellhead (1), wherein one input or output is connected to the metal structure of the wellhead (2) and a second input or output is connected to a grounding device (15), and enabled to receive or transmit a signal from or to the downhole instrument module (8); The grounding device (15) is located from the casing string at a distance that enables to detect the potential difference between the grounding device and the casing string.
A downhole transceiver arrangement, comprising a contact element (10) for electrical contact with a casing string, downhole instrument module (8), downhole pumping equipment (11), or tubing (4) electrically isolated from the string of casing metal tubes (3) using at least one centralizer (7) made of dielectric material, is run into the well.
A contact element (10) is installed under the downhole instrument module so that the distance to the edge of the casing string (3) is more than 5 meters. If it is necessary to install the contact element (10) at a distance of less than 5 meters from the edge of the casing string (3), then a tubing (4) of 5 or more meters is installed below the lower contact element (10).
A downhole instrument module (8) comprises a dielectric insert (9), measuring instruments and sensors (for example, but not limited to, a flow meter, moisture meter, pressure sensor, temperature sensor, etc.), a receiving and transmitting device, a self-contained power system and, when needed, the control devices (for example, but not limited to, valves, samplers, etc.) A downhole instrument module (8) using a dielectric insert (9) conventionally divides casing string (3) into conventionally “lower” and “upper” parts. The housing of the downhole instrument module (8) should not have any electric contact with the casing string (3).
A downhole transceiver arrangement between point A (12) and point B (13) represents a downhole instrument module, tubing (4), or other downhole pumping equipment (11) that is electrically isolated from the casing string (3) for a length of 10 to 100 meters. A closing point of tubing with the casing string A (12) can be formed at any place located above the electrically insulated part up to the wellhead (1). The electrical isolation from the casing string (3) is provided by centralizers (7) made of dielectric material. The number of centralizers (7) and their overall dimensions are determined by the design and curvature of the well.
A downhole transceiver arrangement can be installed in the well both with and without the downhole pumping equipment, and it can be used during the process operations in the well in order to monitor parameters and control the process.
A downhole transceiver arrangement may be used without a string of tubing (
Signal transmission. A downhole instrument module (8) transmits the signal by changing the potential of the “upper” part (point A (12)) of the casing string (3) relative to the “lower” part (point B (13)), wherein the change in potential begins to propagate along the entire length of the string and after a time ‘t’ reaches the wellhead (1). The receiver (14) on the wellhead (1) receives a signal on the change in the string potential relative to the grounding device (15).
Signal reception. When a command is transmitted from the wellhead (1) to the downhole instrument module (8), the wellhead transmitter (14) changes the potential of the casing string (3) relative to the grounding device (15), and the change in potential begins to propagate along the entire length of the string and, after a time ‘t’, reaches the downhole transceiver arrangement and the losses during signal transmission from the point (A) (12) to the point (B) (13) cause a potential difference between points A (12) and B (13), which is detected by the receiver of the downhole instrument module (8).
These application materials disclosed the preferred embodiment of the claimed technical solution, which should not be used to limit its other, particular embodiments that are within the scope of the claimed legal protection and are obvious to those skilled in the relevant art.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022130056 | Nov 2022 | RU | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/RU2022/000344 | 11/21/2022 | WO |
