A geothermal wellhead signal adapter

Abstract

The present invention provides a geothermal wellhead signal adapter, comprising an outer tube, a thermal insulation sleeve disposed inside the outer tube, and a core tube coaxially disposed inside the thermal insulation sleeve; both ends of the core tube extend out of the outer tube, a flange is fixedly connected to one end of the core tube, both axial ends of the core tube are open, and the space inside the core tube serves as a heat transfer medium delivery channel. A socket is mounted on the outer tube, one axial end of the thermal insulation sleeve is close to the socket, and a temperature sensor conductive ring and a cable conductive ring are disposed outside the other axial end of the thermal insulation sleeve; a temperature sensor connecting wire and a cable connecting wire are disposed inside the thermal insulation sleeve, the socket and the temperature sensor connecting wire are connected to the temperature sensor conductive ring, and the socket and the cable connecting wire are connected to the cable conductive ring. The geothermal wellhead signal adapter of the present invention is not easily damaged by temperature influences because the temperature sensor connecting wire and the cable connecting wire are buried in the thermal insulation sleeve, thereby achieving stable transmission and measurement of temperature signals.

Description

Technical Field

[0001] The present invention belongs to the technical field of geothermal energy development equipment, relates to a geothermal field monitoring device for a medium-deep geothermal well, and specifically relates to a geothermal well wellhead signal adapter. Background Art

[0002] Geothermal energy is a clean and renewable energy source. Currently, the mainstream methods of geothermal energy development and utilization include shallow ground source heat pumps, medium-deep hydrothermal type, medium-deep heat exchange type and dry hot rock geothermal. Among them, medium-deep geothermal energy has huge development potential and has become a major direction of geothermal energy development.

[0003] The main process of medium-deep geothermal energy development is: heat transfer through contact between external heat exchangers and rock and soil, and then output of hot fluid through built-in insulation inner tubes. The hot fluid passes through the heat exchange station for energy transfer to form a cycle. The heat transfer process between the hot fluid, the heat exchanger tube wall and the surrounding rock and soil is a complex non-steady-state heat transfer process. In this non-steady-state heat transfer process, the heat transfer characteristics will be affected by the thermophysical parameters of the rock and soil and the geothermal field. Therefore, the geothermal field needs to be monitored during the development of medium-deep geothermal energy.

[0004] The main method of monitoring the geothermal field of medium-deep geothermal wells is to bury a buried pipe heat exchanger in the geothermal well. Temperature sensors are installed on the inner and outer pipe walls of the buried pipe heat exchanger to achieve long-term dynamic temperature measurement. The temperature sensors usually adopt distributed optical fiber sensors or digital temperature sensors. These two types of sensors need to be connected to the ground signal processor through optical fiber cables or cables for data transmission, storage and analysis.

[0005] The following are the main issues encountered in the actual construction and application of geothermal field monitoring systems: First, the connection between the ground signal processor and the main temperature measurement cable is exposed to a variety of environmental factors such as high temperature, high pressure, corrosion, oxidation, hydrogen loss, magnetic field interference, and radiation. This can easily damage the connection, resulting in unstable or even interrupted signal transmission. Second, the connection lines between the temperature sensor, temperature measurement optical cable or electrical cable, heat exchanger, and ground signal processor are relatively complex. During on-site installation, careless operation can easily damage the temperature measurement cable, resulting in failure of the geothermal field monitoring system installation. Summary of the Invention

[0006] In view of the defects and shortcomings of the existing technology, the purpose of the present invention is to provide a geothermal well wellhead signal adapter to solve the technical problem that when monitoring the geothermal field of medium and deep geothermal wells in the existing technology, the connection between the ground signal processor and the temperature measurement cable is easily damaged, resulting in unstable or even interrupted signal transmission.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0008] A geothermal wellhead signal adapter includes an outer tube, both axial ends of the outer tube are open, the space inside the outer tube is divided into a first cavity, a second cavity and a third cavity from left to right, and a first step and a second step are provided on the inner wall of the outer tube from left to right, the first step is located at the junction of the first cavity and the second cavity, and the second step is located at the junction of the second cavity and the third cavity.

[0009] An insulating sleeve is provided in the third cavity, and a core tube is coaxially provided in the insulating sleeve; one end of the core tube passes through the first cavity and the second cavity and extends out of one end of the outer tube, a flange is fixedly connected to the end of the core tube extending out of the outer tube, and the other end of the core tube passes through the insulating sleeve and extends out of the other end of the outer tube; both axial ends of the core tube are open, and the space inside the core tube is a heat transfer medium conveying channel.

[0010] A socket is installed on the outer tube, one axial end of the thermal insulation bushing is close to the socket, and a temperature sensor conductive ring and a cable conductive ring are arranged on the outside of the other axial end of the thermal insulation bushing; a first wiring hole and a second wiring hole are opened in the axial direction of the thermal insulation bushing, a temperature sensor connecting wire is arranged in the first wiring hole, and a cable connecting wire is arranged in the second wiring hole.

[0011] One end of the temperature sensor connecting wire and the cable connecting wire are both connected to the socket, the other end of the temperature sensor connecting wire passes through the first wiring hole and is connected to the temperature sensor conductive ring, and the other end of the cable connecting wire passes through the second wiring hole and is connected to the cable conductive ring.

[0012] The present invention also has the following technical features:

[0013] The outer tube is composed of an insulation layer setting section, an outer tube main section and an insulation tube connecting section from left to right. A first outer tube axial shoulder is provided at the end face of one end of the outer tube main section, and a second outer tube axial shoulder is provided at the end face of the other end of the outer tube main section; the socket is installed at the outer tube main section.

[0014] An outer insulation layer is arranged outside the insulation layer setting section, one end of the outer insulation layer exceeds one end of the outer tube and covers the outside of the core tube, and the other end of the outer insulation layer is connected to the socket installation section.

[0015] The outer surface of the thermal insulation pipe connecting section is provided with a thermal insulation pipe connecting thread.

[0016] A plurality of sealing rings are arranged on the other end of the core tube.

[0017] The flange comprises a flange body fixedly connected to the core tube, a flange center through hole is provided in the middle of the flange body, and a plurality of bolt holes are provided on the flange around the flange center through hole.

[0018] The socket includes a socket body installed on the outer tube, a plurality of socket mounting holes are provided around the socket body, and a first wiring jack and a second wiring jack are provided in the middle position of the socket body; a first wiring post is installed in the first wiring jack, and the first wiring post is connected to one end of the temperature sensor connecting line; a second wiring post is installed in the second wiring jack, and the second wiring post is connected to one end of the cable connecting line.

[0019] Compared with the prior art, the present invention has the following beneficial technical effects:

[0020] (I) The geothermal wellhead signal adapter of the present invention comprises a socket, a temperature sensor conductive ring, a cable conductive ring, a temperature sensor connecting wire and a cable connecting wire, which constitute a signal transmission structure capable of transmitting the temperature signal measured by the temperature sensor of the temperature measuring short section to a ground signal processor. Since the temperature sensor connecting wire and the cable connecting wire are buried in the thermal insulation bushing, they are not easily damaged by temperature, thereby achieving stable transmission and measurement of the temperature signal.

[0021] (II) The geothermal wellhead signal adapter of the present invention uses a socket to achieve connection with a ground signal processor, simplifies the originally complex connection lines, and improves installation efficiency, success rate and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the overall structure of the geothermal wellhead signal adapter.

[0023] Figure 2 Schematic diagram of the structure of the outer tube.

[0024] Figure 3 Schematic diagram of the structure of the thermal insulation bushing.

[0025] Figure 4 It is a structural diagram of the flange.

[0026] Figure 5 This is a front view of the socket.

[0027] Figure 6 A side view of the socket.

[0028] The meanings of the various numbers in the figure are: 1-outer tube, 2-thermal insulation bushing, 3-core tube, 4-flange, 5-heat transfer medium transmission channel, 6-socket, 7-temperature sensor conductive ring, 8-cable conductive ring, 9-first wiring hole, 10-second wiring hole, 11-temperature sensor connecting wire, 12-cable connecting wire, 13-outer insulation layer, 14-sealing ring;

[0029] 101-first cavity, 102-second cavity, 103-third cavity, 104-first step, 105-second step, 106-insulation layer setting section, 107-outer tube main section, 108-insulation tube connecting section, 109-outer tube first shoulder, 110-outer tube second shoulder, 111-insulation tube connecting thread;

[0030] 201 - first section of the thermal insulation bushing, 202 - second section of the thermal insulation bushing, 203 - third section of the thermal insulation bushing, 204 - first shoulder of the thermal insulation bushing, 205 - second shoulder of the thermal insulation bushing;

[0031] 401-flange body, 402-flange center through hole, 403-bolt hole.

[0032] 601-socket body, 602-socket mounting hole, 603-first wiring jack, 604-second wiring jack, 605-first terminal, 606-second terminal.

[0033] The technical solution of the present invention is further described below in conjunction with embodiments. DETAILED DESCRIPTION

[0034] It should be noted that, unless otherwise specified, all components used in the present invention are components known in the art.

[0035] In the present invention:

[0036] The cable is a cable with a cable-type composite thermal insulation pipe known in the prior art. When the cable-type composite thermal insulation pipe is actually used, multiple sections of the cable-type composite thermal insulation pipe are usually connected in series to form an insulation pipe string.

[0037] The temperature sensor is a temperature sensor of a geothermal well temperature measuring nipple known in the prior art.

[0038] In accordance with the above technical solution, specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent changes made on the basis of the technical solution of this application fall within the protection scope of the present invention.

[0039] Example:

[0040] This embodiment provides a geothermal wellhead signal adapter, such as Figure 1 and Figure 2As shown, a geothermal wellhead signal adapter includes an outer tube 1, both axial ends of the outer tube 1 are open, and the space inside the outer tube 1 is composed of a first cavity 101, a second cavity 102, and a third cavity 103 from left to right. A first step 104 and a second step 105 are provided on the inner wall of the outer tube 1 from left to right. The first step 104 is located at the junction of the first cavity 101 and the second cavity 102, and the second step 105 is located at the junction of the second cavity 102 and the third cavity 103.

[0041] A heat-insulating bushing 2 is provided in the third cavity 103, and a core tube 3 is coaxially provided in the heat-insulating bushing 2; one end of the core tube 3 passes through the first cavity 101 and the second cavity 102 and extends out of one end of the outer tube 1; a flange 4 is fixedly connected to the end of the core tube 3 extending out of the outer tube 1; the other end of the core tube 3 passes through the heat-insulating bushing 2 and extends out of the other end of the outer tube 1; both axial ends of the core tube 3 are open, and the space inside the core tube 3 is a heat transfer medium conveying channel 5;

[0042] A socket 6 is installed on the outer tube 1, and one axial end of the thermal insulation bushing 2 is close to the socket 6. A temperature sensor conductive ring 7 and a cable conductive ring 8 are provided on the outside of the other axial end of the thermal insulation bushing 2. A first wiring hole 9 and a second wiring hole 10 are opened in the axial direction of the thermal insulation bushing 2. A temperature sensor connecting wire 11 is provided in the first wiring hole 9, and a cable connecting wire 12 is provided in the second wiring hole 10.

[0043] One end of the temperature sensor connecting wire 11 and the cable connecting wire 12 are both connected to the socket 6, the other end of the temperature sensor connecting wire 11 passes through the first wiring hole 9 and is connected to the temperature sensor conductive ring 7, and the other end of the cable connecting wire 12 passes through the second wiring hole 10 and is connected to the cable conductive ring 8.

[0044] In this embodiment, the heat insulating sleeve 2 is wound and fixed on the outer surface of the core tube 3 , and the core tube 3 and the flange 4 , as well as the core tube 3 and the outer tube 1 , are fixedly connected by welding.

[0045] In this embodiment, Figure 2 and Figure 3 As shown, the thermal insulation sleeve 2 is divided into three sections from left to right. The intersection of the first section 201 and the second section 202 forms the thermal insulation sleeve's first shoulder 204, and the intersection of the second section 202 and the third section 203 forms the thermal insulation sleeve's second shoulder 205. The end surface of one lateral end of the thermal insulation sleeve 2 abuts against the first step 104, and the second shoulder 205 abuts against the second step 105. The temperature sensor conductive ring 7 and the cable conductive ring 8 are mounted outside the third section 203 of the thermal insulation sleeve.

[0046] As a specific solution of this embodiment, Figure 2As shown, the outer tube 1 is composed of an insulation layer setting section 106, an outer tube main section 107 and an insulation tube connecting section 108 from left to right. An outer tube first axial shoulder 109 is provided at the end face of one end of the outer tube main section 107, and an outer tube second axial shoulder 110 is provided at the end face of the other end of the outer tube main section 107; the socket 6 is installed at the outer tube main section 107.

[0047] As a specific solution of this embodiment, Figure 1 and Figure 2 As shown, an outer insulation layer 13 is provided outside the insulation layer setting section 106 , one end of the outer insulation layer 13 exceeds one end of the outer tube and covers the outside of the core tube 3 , and the other end of the outer insulation layer 13 is connected to the socket installation section 102 .

[0048] In this embodiment, the outer insulation layer 13 can reduce the heat loss of the geothermal wellhead signal adapter.

[0049] As a specific solution of this embodiment, Figure 2 As shown, a thermal insulation pipe connecting thread 111 is provided on the outer surface of the thermal insulation pipe connecting section 108 .

[0050] In this embodiment, the external thread 105 is used to connect the outer tube of the insulation pipe, and the gap between the other end of the insulation sleeve 2 and the core pipe 3 is the insulation pipe plug-in position 17. The inner tube of the insulation pipe can be inserted into the insulation pipe plug-in position 17. The insulation pipe plug-in position 17 and the insulation pipe connecting thread 111 cooperate to achieve a plug-in connection between the geothermal wellhead signal adapter and the insulation pipe.

[0051] As a specific solution of this embodiment, Figure 1 As shown, a plurality of sealing rings 14 are provided on the other end of the core tube 3. The sealing rings 14 are high-temperature resistant sealing rings known in the prior art. The sealing rings 14 can prevent the heat transfer medium from entering the gap between the core tube 3 and the insulation tube and causing a short circuit in the signal transmission, thereby ensuring that the temperature measurement result is more stable and reliable.

[0052] As a specific solution of this embodiment, Figure 4 As shown, flange 4 includes a flange body 401 fixedly connected to core pipe 3. A flange center hole 402 is defined in the middle of flange body 401. Multiple bolt holes 403 are defined in flange 4 around center hole 402. In this embodiment, bolt holes 14 and the bolts within bolt holes 14 securely connect the geothermal wellhead signal adapter to the primary pipe network.

[0053] As a specific solution of this embodiment, Figure 5 and Figure 6As shown, the socket 6 includes a socket body 601 mounted on the outer tube 1, and a plurality of socket mounting holes 602 are provided around the socket body 601. A first wiring jack 603 and a second wiring jack 604 are provided in the middle of the socket body 601; a first terminal 605 is installed in the first wiring jack 603, and the first terminal 605 is connected to one end of the temperature sensor connecting line 11; a second terminal 606 is installed in the second wiring jack 604, and the second terminal 606 is connected to one end of the cable connecting line 12.

[0054] In this embodiment, the socket 6 is used to connect to the plug of the ground signal processor and transmit the digital signal to the ground signal processor through the temperature measurement bus to achieve the transmission and measurement of the temperature signal. The ground signal processor adopts a computer known in the prior art.

[0055] In this embodiment, the outer tube 1, the core tube 3, and the flange 4 are made of steel. Specifically, the steel material conforms to the American Petroleum Institute standard. The use of steel can improve the strength, lifespan, and temperature and pressure resistance of the geothermal wellhead signal adapter.

[0056] In this embodiment, the thermal insulation sleeve 2 and outer insulation layer 13 are made of alicyclic epoxy fiberglass or polyimide fiberglass. These materials offer lightweight, high mechanical strength, excellent electrical insulation, and low apparent thermal conductivity. These materials meet the electrical conductivity requirements of the geothermal wellhead signal adapter and enhance its strength. Furthermore, these materials can withstand temperatures exceeding 150°C for extended periods, thereby enhancing the heat resistance of the geothermal wellhead signal adapter.

[0057] The installation and working process of the present invention are as follows:

[0058] First, connect the geothermal well temperature measuring nipple, the insulation pipe string and the geothermal well wellhead signal adapter in sequence, and lower and install them in the geothermal well. Then, fix the geothermal well wellhead signal adapter to the primary pipe network through the flange 4.

[0059] Second, after the geothermal well temperature measuring nipple reaches the preset temperature measuring position of the geothermal well, the heat transfer medium is introduced. The heat transfer medium flows to the bottom of the well through the gap between the insulation pipe string and the outer annulus of the buried pipe and completes the heat exchange with the formation. Then, the heat transfer medium flows through the geothermal well temperature measuring nipple, the insulation pipe string, the geothermal well wellhead signal adapter, the flange center through hole 402 and the primary pipe network in sequence, realizing the heat exchange type geothermal well heat extraction.

[0060] Third, during the heat exchange process, the temperature sensor of the geothermal well temperature measuring short section measures the temperature of the geothermal field and the temperature in the central channel of the insulation pipe string in real time. The measured temperature signal is transmitted to the ground signal processor through the insulation pipe string, the temperature sensor conductive ring 7, the temperature sensor connecting line 11 and the socket 6.

[0061] Fourth, during the heat exchange process, electricity is transmitted to the insulation pipe string through the socket 6, the cable connecting line 12 and the cable conductive ring 8 to realize power supply.

Claims

1. A geothermal wellhead signal adapter, comprising an outer tube (1), both axial ends of the outer tube (1) being open, characterized in that: The space inside the outer tube (1) is composed of a first cavity (101), a second cavity (102), and a third cavity (103) from left to right. A first step (104) and a second step (105) are provided on the inner wall of the outer tube (1) from left to right. The first step (104) is located at the junction of the first cavity (101) and the second cavity (102), and the second step (105) is located at the junction of the second cavity (102) and the third cavity (103). A heat-insulating bushing (2) is provided in the third cavity (103), and a core tube (3) is coaxially provided in the heat-insulating bushing (2); one end of the core tube (3) passes through the first cavity (101) and the second cavity (102) and extends out of one end of the outer tube (1); a flange (4) is fixedly connected to the end of the core tube (3) extending out of the outer tube (1); the other end of the core tube (3) passes through the heat-insulating bushing (2) and extends out of the other end of the outer tube (1); both axial ends of the core tube (3) are open, and the space inside the core tube (3) is a heat transfer medium conveying channel (5); The outer tube (1) is provided with a socket (6), one axial end of the heat-insulating bushing (2) is close to the socket (6), and the other axial end of the heat-insulating bushing (2) is provided with a temperature sensor conductive ring (7) and a cable conductive ring (8); a first wiring hole (9) and a second wiring hole (10) are provided in the heat-insulating bushing (2) along the axial direction, a temperature sensor connecting wire (11) is provided in the first wiring hole (9), and a cable connecting wire (12) is provided in the second wiring hole (10); One end of the temperature sensor connecting wire (11) and the cable connecting wire (12) are both connected to the socket (6), the other end of the temperature sensor connecting wire (11) passes through the first wiring hole (9) and is connected to the temperature sensor conductive ring (7), and the other end of the cable connecting wire (12) passes through the second wiring hole (10) and is connected to the cable conductive ring (8); The outer tube (1) comprises, from left to right, a heat-insulating layer setting section (106), an outer tube main section (107), and a heat-insulating tube connecting section (108); a first outer tube axial shoulder (109) is provided at the end surface of one end of the outer tube main section (107), and a second outer tube axial shoulder (110) is provided at the end surface of the other end of the outer tube main section (107); the socket (6) is installed at the outer tube main section (107); The flange (4) comprises a flange body (401) fixedly connected to the core tube (3), a flange center through hole (402) is provided in the middle of the flange body (401), and a plurality of bolt holes (403) are provided on the flange (4) around the flange center through hole (402).

2. The geothermal wellhead signal adapter according to claim 1, characterized in that: An outer insulation layer (13) is provided outside the insulation layer setting section (106), one end of the outer insulation layer (13) exceeds one end of the outer tube and covers the outside of the core tube (3), and the other end of the outer insulation layer (13) is connected to the socket installation section.

3. The geothermal wellhead signal adapter according to claim 1, characterized in that: The outer surface of the thermal insulation pipe connecting section (108) is provided with a thermal insulation pipe connecting thread (111).

4. The geothermal wellhead signal adapter according to claim 1, characterized in that: A plurality of sealing rings (14) are provided on the outside of the other end of the core tube (3).

5. The geothermal wellhead signal adapter according to claim 1, characterized in that: The socket (6) comprises a socket body (601) mounted on an outer tube (1), a plurality of socket mounting holes (602) are provided around the socket body (601), and a first wiring jack (603) and a second wiring jack (604) are provided in the middle of the socket body (601); a first wiring post (605) is installed in the first wiring jack (603), and the first wiring post (605) is connected to one end of the temperature sensor connecting line (11); a second wiring post (606) is installed in the second wiring jack (604), and the second wiring post (606) is connected to one end of the cable connecting line (12).

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