Patent Application
20240301770
The present disclosure relates generally to downhole tools and more particularly, but not by way of limitation, to a downhole suction tool.
This section provides background information to facilitate a better understanding of the various aspects of the disclosure. It should be understood that the statements in this section of this document are to be read in this light, and not as admissions of prior art.
During the drilling process, bits of the formation being drilled are dislodged and become entrained as debris within fluid that is typically circulated through and around the drill string. Depending on the type and size of the debris, components of the drill string can become damaged and, in severe cases, fail. In order to limit damage and reduce downtime of the drilling operation, it is desirable to filter out the entrained debris from the fluid before the fluid passes through sensitive components of the drill string.
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 to be used as an aid in limiting the scope of the claimed subject matter.
According to aspects of the disclosure, a downhole tool includes: a motor; a pump driven by the motor and configured to draw well fluid into the downhole tool; a screen section disposed below the pump and configured to filter out debris from the well fluid before the well fluid enters the pump; a first port disposed between the motor and the pump and configured to direct fluid from the motor to an annulus surrounding the downhole tool; and a second port disposed between the motor and the pump and configured to direct fluid from the pump to the annulus surrounding the downhole tool.
In some aspects, the downhole tool further comprises a scrubbing section disposed below the screen section.
In some aspects, the scrubbing section comprising a casing brush arranged to displace well fluid down hole when the scrubbing section rotates.
In some aspects, the downhole tool further comprises a third port formed through the downhole tool below the scrubbing section and configured to receive fluid from the annulus.
In some aspects, the downhole tool further comprises a flapper valve disposed below the screen section and configured to prevent fluid from flowing back down the downhole tool.
In some aspects, the downhole tool further comprises a sub configured to selectively fail due to tension so that the downhole tool may be removed.
In some aspects, the downhole tool further comprises a sub configured to selectively fail due to torsion so that the downhole tool may be removed.
In some aspects, the downhole tool further comprises a crossover sub that comprises the first and second ports, wherein the crossover sub comprises a diameter that helps to divide fluid flow from the first and second ports.
In some aspects, the screen section comprises a cylindrically shaped screen that filters out debris from fluid as is flows through the screen section.
According to aspects of the disclosure, a downhole tool comprising: a crossover sub comprising a first set of ports configured to direct a fluid flowing downhole to pass from an interior of the downhole tool to an annulus surrounding the downhole tool, a second set of ports configured to direct the fluid flowing uphole to pass from an interior of the downhole tool to the annulus, wherein the first set of ports periodically align with ports of a head that rotates within the downhole tool to allow fluid to flow from the crossover sub into the annulus.
In some aspects, the head is rotationally driven by a motor positioned uphole from the crossover sub.
In some aspects, the head is coupled to a pump positioned downhole from the crossover sub, wherein the pump is configured to draw fluid into the downhole tool.
In some aspects, the downhole tool further comprises a screen section positioned downhole from the crossover sub and configured to filter out debris from fluid flowing uphole through the downhole tool.
In some aspects, fluid from the first port is directed downhole through the annulus to a drill bit of the downhole tool.
In some aspects, the drill bit comprises a port through which fluid may flow from the annulus into the downhole tool.
In some aspects, the downhole tool further comprises a scrub section positioned downhole of the crossover sub and comprising a casing brush arranged in a spiral and configured to propel fluid downhole toward a drill bit of the downhole tool.
According to some aspects, a method of removing debris from a fluid in a wellbore includes: flowing the fluid through a drill string to a downhole tool. The downhole tool comprises a motor; a pump driven by the motor and configured to draw the fluid into the downhole tool from the wellbore; a screen section disposed below the pump and configured to filter out debris from the fluid before the fluid enters the pump; a first port disposed between the motor and the pump and configured to direct the fluid from the motor to an annulus surrounding the downhole tool and downhole toward a drill bit of the tool; and a second port disposed between the motor and the pump and configured to direct the fluid from the pump to the annulus and uphole.
In some aspects, the downhole tool further comprises a scrubbing section disposed below the screen section.
In some aspects, the scrubbing section further comprises a casing brush helically arranged to displace the fluid downhole when the scrubbing section rotates.
In some aspects, during operation of the downhole tool, the fluid flows downhole through the motor and simultaneously the fluid flows uphole through the pump.
A more complete understanding of the subject matter of the present disclosure may be obtained by reference to the following Detailed Description when taken in conjunction with the accompanying Drawings wherein:
It is to be understood that the following disclosure provides many different embodiments, or examples, for implementing different features of various embodiments. Specific examples of components and arrangements are described below to simplify the disclosure. These are, of course, merely examples and are not intended to be limiting. The section headings used herein are for organizational purposes and are not to be construed as limiting the subject matter described. Reference will now be made to more specific embodiments of the present disclosure and data that provides support for such embodiments. However, it should be noted that the disclosure below is for illustrative purposes only and is not intended to limit the scope of the claimed subject matter in any way.
Crossover sub 125 includes ports 126 and ports 132. Crossover sub 125 enables well fluid to exit ports 126 to flow down hole in the annulus surrounding tool 100 and enables well fluid that has been suctioned up by tool 100 to exit ports 132 to flow up hole in the annulus surrounding tool 100. A diameter of crossover sub 125 at its largest value is sized to extend close to the wall of the well casing to help divide the fluid flow from ports 126/132. In some aspects, the relative diameters and/or number of ports may be tuned to assist with balanced flow of the well fluid from ports 126/132. A top of flex shaft 124 includes a head 127 that includes a plurality of ports that periodically align with ports 126 as flex shaft 124 rotates to allow well fluid to pass therethrough. A lower portion of head 127 rotationally seals against an inner wall of crossover sub 125, and well fluid that has been suctioned up by tool 100 is forced to exit crossover sub 125 via ports 132.
Pump section 106 includes a stator 128 and a rotor 130. Rotor 130 is driven by flexshaft 124. Pump section 106 is configured to create negative pressure below rotor 130 to draw fluid up through pump section 106. Fluid that is pumped through pump section 106 exits tool 100 through ports 132 into the annulus formed between tool 100 and the well bore. The fluid then continues up hole and is recovered and may be reused etc. Ports 126/132 cross over one another, with ports 126 directing fluid down hole and ports 132 directing fluid up hole.
A sub 134 connects an inlet of pump section 106 to screen section 108. Screen section 108 includes a screen 136 that extends within a screen housing 138. In some aspects, screen 136 is generally cylindrically shaped and includes perforations that filter out debris contained within well fluid that is being pumped up hole by pump section 106. For example, as fluid flows up tool 100 from pump section 106 and into screen section 108, screen 136 allows fluid to pass through screen 136, but debris etc. is not permitted to flow past screen 136. A sub 139 includes a canfield bushing to concentrically secure screen 136 within screen housing 138. Screen 136 may comprise a mesh or perforated material etc. that permits fluid to flow through, while preventing debris etc. from flowing through. The permeability of screen 136 may be selected depending on the anticipated size of the debris expected to be contained within the well fluid. As illustrated, screen 136 is a long cylindrical structure that threads into sub 139.
Tool 100 includes several safety features to permit removal of tool 100. Sub 144 includes a shear joint designed to fail in the presence of sufficient tensile loads and sub 146 is designed to fail in the presence of sufficient torque. Subs 144 and 146 allow tool 100 to be removed from the hole to save/protect tool 100. The remaining portion of the string can then be fished from the well.
Wash pipe 110 is connected below screen section 108. Wash pipe 110 is shown illustrated as a single pipe section for the purposes of clarity. In various aspects, wash pipe 110 may comprise multiple pipe sections and may span several thousand feet. For example, tool 100 may be arranged with top sub 102, power section 104, pump section 106, and screen section 108 arranged in a vertical section of a well and with wash pipe 110 and scrub section 112 positioned down hole (e.g., up to several thousand feet from screen section 108 in a horizontal section of the well). Wash pipe 110 may include one or more flapper valves 140. Flapper valves 140 prevent fluid from backflowing down tool 100.
Scrub section 112 is connected below wash pipe 110. Scrub section 112 is configured to help breakup down hole debris and includes a casing brush 142, ports 148, and drill bit 150. Casing brush 142 is designed to help break up sand, debris, etc. Casing brush 142 includes a plurality of brushes that extend radially outward. Each brush is helically arranged about scrub section 112 such that as tool 100 rotates, well fluid surrounding tool 100 is driven down toward drill bit 150 (e.g., similar to the action of a propeller). This spiral arrangement is opposite to the typical arrangement that is ordinarily designed to draw fluid up the annulus. The benefit of the spiral arrangement used by tool 100 is that well fluid is encourage down toward ports 148 and drill bit 150 where the fluid may be suctioned into scrub section 112. The primary flow path for well fluid to be suctioned into tool 100 is via suction ports formed through drill bit 150. For example, the suction ports formed through the drill bit create a flow path from the annulus surrounding tool 100 into the drill bit 150 and then up through wash pipe 110 to be fed into screen section 108. In some aspects, drill bit 150 is a mill type bit. Using a mill type bit allows for larger suction ports than some other drill bit types. Ports 148 offer a secondary flow path for well fluid to be suctioned into scrub section 112.
During operation of tool 100, a flow path of fluid is as follows: fluid is pumped down through tool 100 into power section 104. The flow of fluid into power section 104 causes rotor 116 to rotate. The rotation of rotor 116 drives flexshaft 118, which in turn drives driveshaft 122, flexshaft 124, and rotor 130. Fluid that flows through power section 104 and enters into driveshaft 122 via ports of flex shaft 118. Fluid travels from driveshaft 122 into the annulus through ports 123 in the head of flex shaft 124 first, then through ports 126 of crossover sub 125. Fluid flows down the annulus toward drill bit 150. Fluid then fluid then flows through ports in drill bit 150 and into tool 100. Pump section 106, which is driven by power section 104, creates suction that draws fluid up tool 100 toward screen section 108. Fluid then flows through screen 136, where debris is filtered out from the fluid. Fluid then continues upward through tool 100 and is drawn through pump section 106. Fluid then enters crossover sub 125 where it is directed into the annulus through ports 132, but at a point above the exit for the fluid from ports 126. Fluid then flows up the annulus and can be captured and recycled through tool 100.
Although various embodiments of the present disclosure have been illustrated in the accompanying Drawings and described in the foregoing Detailed Description, it will be understood that the present disclosure is not limited to the embodiments disclosed herein, but is capable of numerous rearrangements, modifications, and substitutions without departing from the spirit of the disclosure as set forth herein.
The term “substantially” is defined as largely but not necessarily wholly what is specified, as understood by a person of ordinary skill in the art. In any disclosed embodiment, the terms “substantially”, “approximately”, “generally”, and “about” may be substituted with “within [a percentage] of” what is specified, where the percentage includes 0.1, 1, 5, and 10 percent.
The foregoing outlines features of several embodiments so that those skilled in the art may better understand the aspects of the disclosure. Those skilled in the art should appreciate that they may readily use the disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the disclosure. The scope of the invention should be determined only by the language of the claims that follow. The term “comprising” within the claims is intended to mean “including at least” such that the recited listing of elements in a claim are an open group. The terms “a”, “an”, and other singular terms are intended to include the plural forms thereof unless specifically excluded.
Conditional language used herein, such as, among others, “can”, “might”, “may”, “e.g.”, and the like, unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or states. Thus, such conditional language is not generally intended to imply that features, elements and/or states are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without author input or prompting, whether these features, elements and/or states are included or are to be performed in any particular embodiment.
While the above detailed description has shown, described, and pointed out novel features as applied to various embodiments, it will be understood that various omissions, substitutions, and changes in the form and details of the devices or algorithms illustrated can be made without departing from the spirit of the disclosure. As will be recognized, the processes described herein can be embodied within a form that does not provide all of the features and benefits set forth herein, as some features can be used or practiced separately from others. The scope of protection is defined by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
Although various embodiments of the method and apparatus of the present invention have been illustrated in the accompanying Drawings and described in the foregoing Detailed Description, it will be understood that the invention is not limited to the embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the spirit of the invention as set forth herein.
This patent application claims priority from, and incorporates by reference the entire disclosure of, U.S. Provisional Application No. 63/345,109 filed on Mar. 6, 2023.
| Number | Date | Country | |
|---|---|---|---|
| 63450109 | Mar 2023 | US |
