RU2591863C2 - Tool column - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: tool string extending in a longitudinal direction and comprising a first string part and a second string part, each having a centre axis and comprising: an electrical connection in a first end and a fluid channel extending at least partly through string part. Furthermore, tool string comprises a connecting element rotatably connected to one string part and adapted to be threadably connected to a threaded portion of other string part to join electrical connections of first and second string parts. Furthermore, present invention relates to a method for assembling two string parts of a tool string by rotating a connecting element.

EFFECT: improvement of string due to possibility of transmission as fluid medium, and electric energy from one part of string to other.

13 cl, 6 dwg

Description

FIELD OF THE INVENTION

The present invention relates to a tool string for hanging in a well, said tool string extending in the longitudinal direction and comprising a first part of the column and a second part of the column, each of which has a central axis and contains an electrical connector at the first end and a fluid passage passing through at least partially through said portion of the column. In addition, the present invention relates to a method for assembling the two mentioned parts of the tool string.

State of the art

The rate of production from oil and gas wells and the surrounding productive horizon is becoming increasingly significant due to decreasing oil reserves. Therefore, for the search and production of oil and gas, more and more modern tools are developed and used. Instruments placed inside the well are often assembled or mated into an instrumental string containing a plurality of instruments, for example, driven instruments for advancing the instrumental string forward in inclined sections of the well and / or working tools for performing various operations within the well.

Various methods are known in the art for mating pipe sections for use in a drill string or casing. Such pipe connections may provide a fluid tight connection between the pipe sections and may also include an electrical connection for transmitting electricity. However, known connections do not provide the necessary connection between modern tools and tool parts. The operation of existing downhole tools, such as downhole tractors, requires the supply of both electricity and hydraulic fluid. Thus, there is a need for such a connection between the various parts of the tool string, which would provide the ability to transfer both fluid and electricity. Some downhole tools require several separate fluid channels extending between different parts of the tool string. Mentioned connection must be strong and able to withstand significant tensile forces and torsion during downhole placement. At the same time, the assembly of the mentioned connection should be relatively simple and quick.

Disclosure of invention

The objective of the present invention is to completely or partially eliminate the above disadvantages inherent in the existing level of technology. In particular, an object of the present invention is to provide an improved tool string in which electric power and fluid (fluids) can be transferred from one part of the string to another. In addition, the task is to provide such a connection between two parts of the column, in which the channels for the fluid in each part of the column are brought into communication by the fluid and the wires in each part of the column are connected.

The above tasks, together with many other tasks, advantages and features that will become more clear from the following description, are achieved by the proposed solution, in particular, an instrumental string for hanging in a well, and this instrumental string extends in the longitudinal direction and contains:

- the first part of the column and the second part of the column, each of which has a Central axis and contains:

- electrical connector at the first end,

- a fluid channel extending, at least in part, through said portion of the tool string;

- a connecting element rotatably connected to one part of the tool string and threadedly connected to a threaded portion of the other tool string part for interfacing the electrical connectors of said first and second column parts,

moreover, one of the said parts of the column contains a pipe connector extending longitudinally from its first end into the fluid channel of the other part of the column, when the said parts of the column are connected to each other by said connecting element, said pipe connector being eccentric relative to the central axis to prevent rotation of the said parts of the column relative to each other.

Thus, a connection can be provided for transferring both electric power and fluid between the two parts of the tool string. This compound has the necessary rigidity to provide and maintain a fluid tight seal between the fluid channels of said first and second column parts. In addition, twisting and bending of electrical wires is prevented.

In one embodiment of the invention, one of said column parts may comprise at least two pipe connectors.

In another embodiment of the invention, one of said column parts may comprise a guide pin, and the other column part may comprise an opening for receiving said guide pin when said column parts are connected to each other by said connecting element.

In addition, said connecting element may comprise two mating coupling elements configured to connect to each other around a section of one of said column parts.

In addition, said connecting element may comprise an external threaded portion.

In addition, the said connecting element may be located around the protrusion of one of the said parts of the column, having a diameter reduced in comparison with the maximum diameter of the said part of the column.

In addition, the said connecting element can be located in the recess of one of the parts of the column, as a result of which the movement of this connecting element in the longitudinal direction is essentially prevented.

In addition, the longitudinal movement of said connecting element towards said first end can be substantially prevented by the protruding part of said column part, which has an enlarged outer diameter.

Said connecting element may have an outer diameter that is equal to or less than the outer diameter of the tool string.

In addition, the specified connecting element may have an outer diameter that is equal to or less than the minimum outer diameter of the tool string.

In one embodiment of the invention, the pipe connector may include an annular sealing element configured to provide a fluid tight seal between the pipe connector and the corresponding fluid channel into which it passes.

In addition, one of these parts of the column may contain an annular sealing element configured to provide a fluid tight seal between said first and second parts of the column.

In one embodiment of the invention, one of the parts of the string may be a drive unit designed to advance the tool string in the well.

The present invention also relates to a method for assembling two parts of an instrumental string, the method comprising the following steps:

- move the first end of the first part of the column towards the first end of the second part of the column,

- place the guide pin of one of the parts of the column in the hole made in another part of the column,

- connect the threaded section of the connecting element, rotatably connected from one of the parts of the column, with the threaded section of the other part of the column,

- rotate the connecting element to pair the electrical connectors of the aforementioned first and second parts of the column and to press the pipe connector of one part of the column into the hole in fluid communication with the fluid channel of the other part of the column.

Brief Description of the Drawings

In more detail, the invention and its advantages are described below with reference to the accompanying schematic drawings, which, for the purpose of illustration, depict some non-limiting embodiments of the invention, in which:

figure 1 shows the instrumental string suspended in the well;

figure 2 shows the ends of two parts of the column in the assembled state, connected by a connecting element;

on figa and 3b shows a diagram of the end surfaces of two parts of the columns, made with the possibility of assembly;

figure 4 shows a connecting element containing two connectable coupling elements;

figure 5 shows the instrumental column containing the downhole tractor having wheel sections.

All drawings are very schematic and not necessarily drawn to scale. In this case, the drawings show only those parts that are necessary to describe the invention, while other parts are not shown or are conventionally shown.

The implementation of the invention

Figure 1 shows the tool string 1 suspended in the well 4 on the cable 5. The tool string 1 can also be suspended using coiled tubing or may be part of the drill string. The illustrated well includes a casing 14, however tool string 1 may also be used in an open hole.

The instrumental column 1 extends in the longitudinal direction and comprises at least a first part 2 of the column and a second part 3 of the column. The first end 200 of the first part 2 of the column and the first end 400 of the second part 3 of the column are connected by a connecting element 6 located between the two parts 2, 3 of the column in the longitudinal direction. The dashed line in figure 1 shows that part of the first end 200 of the first part of the column passes through the connecting element 6 and into the first end 400 of the second part of the column.

Shown in figure 1, the connection between the first part 2 of the column and the second part 3 of the column is described in more detail below with reference to figure 2. For clarity, the connecting element 6 and part of the second part 3 of the column are cut and shown in cross section.

As mentioned parts 2, 3 of the column, and the connecting element 6 have a circular cross section. A protrusion 27 having a reduced diameter 37b is provided at the first end 200 of the first column portion 2. The protrusion 27 extends between the surface 39 of the first part of the column and the end surface 201. Toward the end surface 201, the protrusion 27 comprises an annular protruding flange 29. Together with the surface 39, the protruding flange 29 defines a recess 28 surrounding the protrusion 27. A plurality of pipe connectors 22, 23, 24 and a guide pin 26. In addition, an electrical connector, such as a plug 21, and an annular seal 33a around a protrusion 27 near the end surface 201 are provided on the end surface 201. from the pipe connectors runs in the longitudinal direction 10 from the end surface 201 towards the free conical end. An annular seal 30, 31 is located at a distance from the conical end, around each of the pipe connectors. The guide pin 26 also extends in the longitudinal direction from the end surface 201 towards the free conical end. Around the protrusion 27, in the recess 28 of reduced diameter is the connecting element 6. The connecting element 6 is formed by two connectable coupling elements 601, 602, as shown in Fig.4. During assembly, two coupling elements 601, 602 are placed in a recess 28 around the protrusion 27 and connected by bolts 62. Thus, the connecting element 6 is rotatably connected to the first part 2 of the column, while the movement of the connecting element in the longitudinal direction is limited by surface 39 and an outstanding the flange 29. The connecting element 6 contains an external threaded section 61, made with the possibility of connection with the threaded section 48 of the second part 3 of the column, as shown in Fig.2. For a person skilled in the art it is obvious that the connecting element can be constructed in various ways without going beyond the scope of the invention. The rotatable connection of the connecting element 6 can be provided in various ways known to a person skilled in the art, for example, using a swivel connection, a spherical hinge and other types of connections that enable the connection of two separate objects with the possibility of rotation relative to each other.

At the first end 400, the second part 3 of the column contains a bore 47 configured to receive a protrusion 27 of the first part 2 of the column and the connecting element 6. The specified bore is surrounded by a threaded section 48 of the second part 3 of the column, and the specified section is configured to connect with the threaded section 61 of the connecting element 6. At one end, the bore 47 is bounded by a surface 401 containing a plurality of holes 42, 43, 44 configured to receive pipe connectors 22, 23, 24, as shown in FIGS. 3a and 3b. The surface 401 further comprises an opening 46 adapted to receive a guide pin 26, and an electrical connector, such as a socket 41, configured to connect to the plug 21, as shown in FIGS. 3a and 3b.

An approximate arrangement of the protruding pipe connectors 22, 23, 24, the guide pin 26 and the plug 21 is shown in Fig. 3a, and the arrangement of the corresponding holes 42, 43, 44 and the socket 41 is shown in Fig. 3b. The pipe connectors 22, 23, 24 are fluidly connected to the respective channels 220, 240 in the first part of the column, and the openings 42, 43, 44 are in fluid communication with the corresponding fluid channels 420, 440 in the second part 3 of the column. By arranging the pipe connectors 22, 23, 24 in the respective openings 42, 43, 44, the fluid channels 220, 240 in the first part of the column are brought into communication by the fluid with the fluid channels in the second part of the column. Similarly, the plug 21 and socket 41 provide an electrical connection between the first and second parts of the column.

As shown in figa and 3b, the pipe connectors 22, 23, 24 of the first part 2 of the column and the corresponding holes 42, 43, 44 in the second part 3 of the column are eccentric relative to the Central axis 10. The location of at least one pipe connector 22, 23 24 eccentrically at a distance from the central axis prevents rotation of the first and second parts 2, 3 relative to each other around the central axis 10. Thus, one or more pipe connectors has the additional function of fixing parts of the column relative to each other as during assembly of parts of the column, and with downhole use of the instrumental column.

The guide pin 26 extends further beyond the end surface 201 than said pipe connectors. Thus, during assembly of the first and second parts of the column, the guide pin 26 is inserted into the hole 46 to control the assembly process and prevent damage that may be caused by rotation or tilt of the parts of the tool column relative to each other. The plug, socket, or pipe connectors may be bent or broken if parts of the column are not properly aligned during assembly and disassembly. When the guide pin 26 is at least partially placed in the hole 46, the two parts of the column are held essentially parallel to each other. Due to the presence of the guide pin, a slight skew of the first and second parts of the column in the connection between them is prevented. Such a slight distortion in the connection itself can lead to leakage in the pipe connectors either due to bending and, as a result, a small separation of the pipe connector, which is an integral part of one end of the tool string parts, with the formation of a gap, or due to the distortion in the holes of the pipe connector, which separate part.

The pipe connectors may be integral parts of one of the mentioned parts of the column or may be separate pipes. One pipe connector can be placed in one part of the tool string, and the other pipe connector in the other part so that when the two parts of the string are mated, the pipe connectors serve as guides in the assembly process.

The connecting element 6 is located in the recess 28 of the first part of the column, and in figure 2, the first part 2 of the column also contains a pipe connector and a pin. However, the connecting element 6 can be located in the recess of the first part of the column, and the pipe connector and the pin can be located in the second part 3 of the column.

Figure 5 shows the downhole tractor 81, which is part of the tool string 1, and two parts 2, 3 of the column are assembled using the connecting element 6 described above. The downhole tractor is suspended and powered by a cable 5 connected to the downhole tractor via an upper connector 71. The downhole tractor 81 comprises an electronics section 72, an electric motor 73, a hydraulic pump 74, and two wheel sections 80 driven by hydraulics. Said wheel sections are in fluid communication with a hydraulic pump 74 and may also be referred to as drive blocks 80 for moving the downhole tractor and tool string in the well forward. The downhole tractor can be connected to one or more working downhole tools 75, which are also part of tool string 1. Such working tools can be a percussion instrument providing axial force in one or more impacts, a key tool that opens or closes valves in the well, positioning a tool, such as a casing collar locator (CCL), a milling tool, a drilling tool, and other similar tools.

The connection between the two parts 2, 3 of the tool string, for example two wheel sections 80 of the downhole tractor, can be used to transfer fluid (s) and / or electricity. Electricity can be transmitted from the cable 5 to the first part of the column and through the plug 21 and socket 41 to the next part of the column.

The pipe connector 22 may be used to connect fluid channels providing pressure fluid from the hydraulic pump 74 to the wheel sections to extend the rotary wheel arms 76. The pipe connector 24 can be used to connect fluid channels providing pressure fluid from the hydraulic pump 74 to the wheel sections to rotate the wheels 77 mounted on the wheel levers 76 clockwise. The pipe connector 23 can be used to connect fluid channels providing pressure fluid from the hydraulic pump 74 to the wheel sections to rotate the wheels 77 mounted on the wheel levers 76 counterclockwise. The pipe connector 25 and hole 45 can be used to connect fluid channels to form a return channel for the fluid supplied to the wheel sections.

By the terms “fluid” or “borehole fluid” is meant any type of fluid that may be present inside oil or gas wells, for example, natural gas, oil, oil-containing drilling fluid, crude oil, water, and other similar substances. By the term "gas" is meant any type of combination of gases that may be present in a well, an equipped well, or in an open hole. The term "oil" refers to any type of combination of oil, for example, crude oil, oily fluid and other similar substances. All of these fluids — gas, oil, and water — may thus contain other elements and substances other than gas, oil, and / or water, respectively.

By the term “rotatably connected” is meant that the first rotatable object is connected to the second object such that the first object can rotate while being connected to the second object, and a connection is maintained between the first object and the second object during rotation of the first object relative to the second object . The term "casing" means any type of pipe, tubing, tubular element, sheathing, string or other similar device used inside the well for the production of oil or natural gas.

In case the tools are not completely submerged in the casing, an downhole tractor can be used to push the tools into the well completely to the required position. An downhole tractor is any type of drive tool that can push or pull tools inside a well, such as Well Tractor®.

Preferred embodiments of the present invention have been described above. However, for a person skilled in the art obvious modifications are possible that do not go beyond the scope of legal protection of the invention defined by the claims.

Claims (13)

1. Tool string (1) for hanging in the well (4), and this tool string runs in the longitudinal direction and contains:
- the first part (2) of the column and the second part (3) of the column, each of which has a central axis (3) and contains:
- an electrical connector (21, 41) at the first end (200, 400) and
a fluid channel (220, 240, 420, 440) passing at least partially through a given part of the column,
- a connecting element (6), rotatably connected to one part of the column and made threaded to a threaded section (48) of the other part of the column for interfacing the electrical connectors of said first and second parts of the column,
moreover, one of the said parts of the column contains a pipe connector (22, 23, 24) extending in the longitudinal direction from its first end into the fluid channel of the other part of the column, when the said parts of the column are connected to each other by a connecting element, said pipe connector being located eccentric relative to the central axis to prevent rotation of said portions of the column relative to each other. 2. The column according to claim 1, characterized in that one of the said parts of the column contains at least two pipe connectors (22, 23, 24). 3. The column according to any one of paragraphs. 1 or 2, characterized in that one of said column parts comprises a guide pin (26), and the other said column section contains an opening (46) for receiving said guide pin when said column parts are connected to each other by said connecting element. 4. The column according to any one of paragraphs. 1 or 2, characterized in that the said connecting element contains two connectable coupling elements (601, 602), made with the possibility of connection with each other around the section (27) of one of the mentioned parts of the column. 5. The column according to any one of paragraphs. 1 or 2, characterized in that the said connecting element contains an external threaded section (61). 6. The column according to any one of paragraphs. 1 or 2, characterized in that the said connecting element is located around the protrusion (27) of one of the mentioned parts of the column having a diameter (37b), reduced in comparison with the maximum diameter of the said part of the column. 7. The column according to any one of paragraphs. 1 or 2, characterized in that the said connecting element is located in the recess (28) of one of the said parts of the column, as a result of which the movement of the said connecting element in the longitudinal direction is essentially prevented. 8. The column according to any one of paragraphs. 1 or 2, characterized in that the movement of said connecting element in the longitudinal direction towards said first end is essentially prevented by the protruding part (29) of said column part, which has an increased outer diameter. 9. The column according to any one of paragraphs. 1 or 2, characterized in that said connecting element has an outer diameter (66) that is equal to or less than the outer diameter (37a) of the tool string. 10. The column according to any one of paragraphs. 1 or 2, characterized in that said pipe connector comprises an annular sealing element (30, 31) configured to provide a fluid tight seal between said pipe connector and a corresponding fluid channel (420, 440) into which it passes . 11. The column according to any one of paragraphs. 1 or 2, characterized in that one of the said parts of the column contains an annular sealing element (33), configured to provide a fluid tight seal between said first and second parts of the column. 12. The column according to any one of paragraphs. 1 or 2, characterized in that one of the aforementioned parts of the column is a drive unit (80), designed to advance the instrumental column in the well. 13. The method of assembly of two parts (2, 4) of the instrumental column (1), and this method contains the following steps:
- move the first end (200) of the first part (2) of the column towards the first end (400) of the second part (3) of the column,
- place the guide pin (26) of one of the parts of the column in the hole (46) in another part of the column,
- connect the threaded section (61) of the connecting element (6), rotatably connected from one of the mentioned parts of the column, with the threaded section (48) of the other part of the column,
- rotate the connecting element for pairing the electrical connectors of the first and second parts of the column and for pressing the pipe connector (22, 23, 24) of one part of the column into the hole (42, 43, 44) in fluid communication with the channel (420, 440) for fluid of another part of the column.

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