CN105547515A - Self-floating undersea temperature detecting system - Google Patents

Abstract

The invention discloses a self-floating undersea temperature detecting system which comprises an undersea signal collecting base station and a temperature detecting probe. The temperature detecting probe can be used for multiple times and fully makes contact with seawater, temperature detecting units are arranged in the temperature detecting probe and combined conveniently and flexibly to output digital signals, and the data quality can be effectively improved; through the undersea signal collecting base station, the instrument recycling rate is guaranteed, and the sea temperature detecting risk is reduced. The self-floating undersea temperature detecting system can detect the undersea temperature both in a neritic region and in an abyssal region and is beneficial for long-term undersea temperature detecting due to long sea staying time.

Description

A self-floating seabed temperature detection system

technical field

The invention belongs to the field of geophysical measurement, and in particular relates to a seabed temperature detection system for geophysical measurement.

Background technique

Seafloor temperature detection is an important means of geophysical methods, especially the temperature gradient detection results in the heat flow region can directly reflect the heat transfer process inside the earth, helping us to carry out research on geodynamics and the evolution process of the internal heat-driven framework in the earth, providing a basis for the seabed The exploration of oil and gas and other mineral resources provides evaluation basis.

At present, seabed temperature detection is mainly realized by oil drilling temperature measurement and seabed heat flow meter detection. Among them, oil drilling temperature measurement is mainly carried out in oil areas and shallow sea areas, with many operating conditions, high cost and low efficiency; compared with oil drilling temperature measurement, seabed heat flow meters are simple to operate and have higher efficiency. Internationally, sea bottom heat flow meters are mainly used. Subsea temperature detection. During operation, the submarine heat flow meter is put into the water through the steel cable, and inserted into the seabed sediment under the action of gravity. After the temperature of the contact position between the probe of the seabed heat flow meter and the seabed sediment reaches a steady state, the temperature of the seabed is measured through the internal thermal sensor. , which is retrieved by the steel cable after the measurement is completed. At present, there are mainly three types of submarine heat flow meters: Bullard type, Ewing type and Lister type. The common feature of the three is that it is released and recovered by the steel cable. The heat-sensitive elements are mounted at different positions on the inner wall of the reinforced pipe or the outer wall of the steel spear at certain intervals. The heat-sensitive elements are connected to the recording unit at the same time, and the recording unit is placed in a separate pressure container. Inner seal. Submarine heat flow meters can easily measure the temperature of the seabed within a kilometer, but as the depth of seawater increases, the difficulty of detection doubles, the efficiency decreases and the risk greatly increases. When the probe of the submarine heat flow meter is inserted into the sediment, it will cause frictional heat generation, and the specific heat stabilization time is not easy to grasp. At the same time, the seabed temperature in some specific sea areas is affected by the interior of the earth and shows drastic changes over time. A submarine heat flow meter is required. Stay in the sea for a long time to obtain accurate temperature information. In addition, during the working process of the submarine heat flow meter, the measurement ship will drift due to the surge, and the position of the submarine heat flow meter on the seabed may change under the action of the steel cable, which may even cause damage to the submarine heat flow meter and cause the operation to fail. The application of the seabed heat flow meter puts forward a new subject.

In view of the limitation of oil drilling temperature measurement and seabed heat flow meter in the seabed temperature detection process, it is necessary to develop a kind of convenient recovery, long time in the sea, small size and convenient for large-scale seabed seismograph for reference. Self-floating seabed temperature detection system for temperature detection.

Contents of the invention

Aiming at the deficiencies of the existing technology, a seafloor temperature detection system is provided, which has a simple structure, self-floating recovery, and is suitable for long-term seafloor temperature detection, so as to meet the needs of marine geophysical surveys.

In order to achieve the above object, the technical solution of invention is as follows:

A self-floating seabed temperature detection system includes a seabed signal acquisition base station 24 and a temperature measuring probe 4 . Wherein the seabed signal acquisition base station 24 comprises a decoupling mechanism 1, an instrument cabin 2 and a sinking coupling frame 5; the instrument cabin 2 includes an inner single glass cabin ball 10 and an outer protective shell 13; the glass cabin ball 10 is provided with a four-core watertight socket 6, The signal collection base station 24 is connected to the temperature measuring probe 4 through a wire 7 . The outer protective shell 13 of the glass cabin ball is divided into upper and lower parts, both of which are fixed by multiple bolts, and the temperature measuring probe 4 is fixed on the bottom of the outer protective shell 13 by bolts; the top of the outer protective shell 13 is equipped with a decoupling mechanism 1, and the instrument cabin 2 is placed as a whole On the sinking coupling frame 5; the sinking coupling frame 5 is a square frame, with a rigid metal ring in the middle, and the square frame is connected with the rigid metal ring through four steel beams. The metal ring, steel beam, and sinking coupling frame are square. The frames are hollow, and the temperature measuring probe 4 passes through the middle of the metal ring 18 .

In the self-floating seabed temperature detection system, the temperature measuring probe 4 is vertically fixed on the bottom of the outer protective shell 13 by bolts, and the glass cabin ball 10 and the end of the temperature measuring probe 4 are each provided with a four-core watertight socket, and the two pass through RS485 bus 7 connections, the bus is divided into power line, ground line, data line A and data line B. The main body of the temperature measuring probe 4 is cylindrical, 1 to 1.5 meters long, 3 cm in diameter, and 0.5 cm thick, with a conical front end and a four-core watertight socket at the end of the temperature measuring probe; A plurality of circular holes 23 are provided so that seawater can flow freely inside and outside the temperature measuring probe 4 .

Further, a plurality of temperature detection units 21 are placed inside the temperature measurement probe 4 , and the temperature detection units 21 are connected through the RS485 bus 20 and placed vertically inside the temperature measurement probe 4 . A temperature acquisition circuit 22 integrated with a negative temperature coefficient thermistor is placed inside the temperature detection unit 21 . The temperature detection unit 21 is cylindrical and sealed as a whole. There are four-core watertight sockets at the top and bottom of the cylinder, which can be connected to the submarine signal acquisition base station 24 alone or multiple series can be connected to the submarine signal acquisition base station 24 to work. To detect the seafloor temperature gradient. When detecting the seabed temperature gradient, an appropriate length RS485 bus can be selected according to requirements, and the seabed signal acquisition base station 24 communicates and transmits data with the internal temperature detection unit 21 of the temperature measuring probe through the RS485 bus.

In addition, the temperature detection unit 21 integrates a complete temperature acquisition circuit 22, which can directly output digital signals, and the digital signals are transmitted to and stored in the submarine signal acquisition base station 24 through the RS485 bus, and the submarine signal acquisition base station 24 controls the temperature detection unit 21 to work through the RS485 bus Time and determine working parameters such as sampling rate.

Using the technical solution of the present invention can have the following beneficial effects:

1. In the present invention, the submarine signal acquisition base station and the temperature measuring probe are only connected by an RS485 bus containing four wires, which reduces the difficulty of watertight connectors passing through the cabin. Using a single glass cabin ball can communicate with more than 10 temperature detection units inside the temperature measuring probe at the same time, which solves the problem of miniaturization of the seabed temperature detection system.

2. The internal temperature acquisition circuit of the temperature detection unit provided by the present invention integrates a negative temperature coefficient thermistor, and the negative temperature coefficient thermistor has a higher sensitivity than platinum resistors in the seabed temperature range (0°C-10°C), which can realize seabed Temperature detection with high precision. The temperature acquisition circuit realizes the digital output of the temperature at the sampling point, which avoids the interference caused by the long transmission distance between the thermistor and the recording board in the traditional heat flow meter probe, especially when detecting the temperature gradient of the seabed, due to the need to measure the temperature more Point sampling will further cause the analog signal transmission distance to be doubled, and the present invention can effectively improve the quality of acquired data.

3. The self-floating seabed temperature detection system provided by the present invention improves the recovery rate of instruments and reduces the risk of ocean temperature detection, and can detect seabed temperature in both shallow sea areas and deep sea areas. Compared with the traditional seabed heat flow meter, it stays in the sea for a longer time, which is conducive to the acquisition of long-term seabed temperature data; the small size and easy operation are conducive to carrying out large-scale seabed temperature detection operations.

Description of drawings

Fig. 1 is a three-dimensional structural schematic diagram of a self-floating seabed temperature detection system according to the present invention;

Fig. 2 is a schematic cross-sectional structure diagram of a self-floating seabed temperature detection system according to the present invention;

Fig. 3 is a schematic diagram of the sinking coupling frame of the self-floating seabed temperature detection system according to the present invention;

Fig. 4 is a schematic diagram of the cross-sectional structure of the temperature measuring probe in the self-floating seabed temperature detection system according to the present invention;

5 is a structural block diagram of the temperature acquisition circuit in the temperature detection unit of the self-floating seabed temperature detection system according to the present invention;

6 is a circuit diagram of the signal amplification part in the temperature acquisition circuit of the temperature detection unit of the self-floating seabed temperature detection system according to the present invention;

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Apparently, the described embodiments are only some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

A self-floating seabed temperature detection system includes a seabed signal acquisition base station 24 and a temperature measuring probe 4 . Wherein the seabed signal acquisition base station includes a decoupling mechanism 1, an instrument cabin 2 and a sinking coupling frame 5; the instrument cabin 2 includes an inner single glass cabin ball 10 and an outer protective shell 13; the glass cabin ball 10 is provided with a four-core watertight socket 6, and the submarine signal The acquisition base station 24 is connected to the temperature measurement probe 4 through a wire 7 . The outer protective shell 13 of the glass cabin ball is divided into upper and lower parts, both of which are fixed by multiple bolts, and the temperature measuring probe 4 is fixed on the bottom of the outer protective shell 13 by bolts; the top of the outer protective shell 13 is equipped with a decoupling mechanism 1, and the instrument cabin 2 is placed as a whole On the sinking coupling frame 5; the sinking coupling frame 5 is a square frame, with a rigid metal ring in the middle, and the square frame is connected with the rigid metal ring through four steel beams. The metal ring, steel beam, and sinking coupling frame are square. The frames are hollow, and the temperature measuring probe 4 passes through the middle of the metal ring 18 .

Wherein, the seabed signal acquisition base station 24 integrates a direction sensor 15 and an attitude sensor 16 for acquiring the inclination status of the temperature measuring probe 4 inserted into the seabed. Preferably, the present invention uses a HMR3200 type direction sensor with a direction accuracy of 1° and a resolution of 0.1°. The temperature measuring probe 4 is fixed on the bottom of the outer protective shell 13 by bolts. The glass cabin ball 10 and the end of the temperature measuring probe 4 are respectively provided with four-core watertight sockets, which are connected through the RS485 bus. The bus is divided into power lines, ground lines, data Line A and data line B. The bus power supply voltage is 5.2V. In order to ensure the stability of the power supply of the temperature detection unit, a voltage stabilizing circuit is added to the temperature detection unit 21 .

The main body of the temperature measuring probe 4 in the present invention is cylindrical, with a length of 1 to 1.5 meters, a diameter of 3 cm, and a wall thickness of 0.5 cm. The front end is conical, and the tail end is provided with a four-core watertight socket 19; There are multiple round holes 23, seawater can flow freely inside and outside the temperature measuring probe 4; multiple temperature detection units 21 are placed inside the temperature measuring probe 4, and the temperature detection units 21 are connected to the temperature measuring probe through the RS485 bus 20 4 inside. A temperature acquisition circuit 22 integrating a negative temperature coefficient thermistor is placed inside the temperature detection unit 21, and the resistance value of the negative temperature coefficient thermistor used varies from 15.4 kΩ to 9.7 kΩ at 0° C. to 10° C. Compared with platinum resistance thermometers, it has higher sensitivity, which is convenient for high-precision detection of seabed temperature. In order to save the power consumption of the temperature detection unit 21 and facilitate the long-term seabed temperature detection, the temperature acquisition circuit adopts the LPC812 microcontroller, only 16 pins, and the pin functions can realize function switching. In the present invention, pin 1 is allocated as AD chip selection, pin 2 is allocated as AD clock signal, pin 7 is allocated as AD input signal, pin 8 is allocated as AD output signal, and pin 14 is allocated as RS485 bus input signal. Pin 15 is allocated as MAX485 chip selection signal, and pin 16 is allocated as RS485 bus output signal. LPC812 comes with UART (Universal Asynchronous Receiver Transmitter) and contains address registers, which can be set individually. The temperature data acquired by the temperature detection unit 21 is amplified and converted from analog to digital, and sent by LPC812 through UART, modulated by MAX485 chip into RS485 bus mode for transmission. The temperature detection unit 21 is cylindrical and sealed as a whole. The top and bottom of the cylinder are respectively equipped with four-core watertight sockets, which can be connected to the submarine signal acquisition base station 24 alone or multiple serially connected to the submarine signal acquisition base station 24 to work. After serial connection It can detect the seabed temperature gradient. When detecting the seabed temperature gradient, an appropriate length RS485 bus can be selected according to requirements, and the seabed signal acquisition base station 24 communicates and transmits data with the temperature detection unit 21 through the RS485 bus. The specific working mode is that the seabed signal acquisition base station 24 sends the address of the temperature detection unit 21 that needs to obtain data to all temperature detection units 21 through the RS485 bus. LPC812 controls the temperature acquisition circuit 22 to work, and transmits the collected temperature data to the seabed signal acquisition base station 24. If the address is not consistent with itself, no operation is performed to save power consumption.

Further, a complete temperature acquisition circuit 22 is integrated inside the temperature detection unit 21, which can directly output digital signals, and the signal is transmitted to and stored in the submarine signal acquisition base station 24 through the RS485 bus, and the submarine signal acquisition base station 24 controls the temperature detection unit through the RS485 bus 21 working hours and determine the sampling rate and other working parameters.

Specifically, a further detailed description will be given below in conjunction with the accompanying drawings.

As shown in FIG. 1 , it is a three-dimensional structure diagram of a self-floating seabed temperature detection system, including a seabed signal acquisition base station 24 and a temperature measurement probe 4 . Submarine signal acquisition base station 24 comprises decoupling mechanism 1, instrument cabin 2 and sinking coupling frame 5; Placed above the instrument cabin 2, one end of the four steel cables 3 is fixed at the fixed interface of the decoupling mechanism 1, and the other end is locked at the sinking coupling frame 5 with a nut 8, so that the instrument cabin 2 and the sinking coupling frame 5 are fixed. The temperature measuring probe 4 is fixed on the bottom of the outer protective shell 13 of the instrument cabin by bolts, and passes through the middle of the metal ring 18 vertically.

The self-floating seabed temperature detection system has a simple structure and a small volume, and is convenient for offshore operations and large-scale seabed temperature detection operations.

As shown in Figure 2, the glass capsule 10 is a 17-inch glass capsule produced by Vitrovex, which is used to load and protect internal circuits, battery packs and other components and provide buoyancy during recovery. The maximum pressure resistance of the glass capsule 10 is 6,500 meters , which can meet the seabed temperature detection in most sea areas. The glass cabin ball 10 is made up of upper and lower hemispheres, and the middle is sealed by cement and adhesive tape, and the internal negative pressure of the glass cabin ball 10 is kept to ensure that the instrument cabin 2 has good sealing performance after launching. The underwater acoustic sensor 9 is installed on the top of the glass cabin ball 10, and carries out underwater acoustic communication with the outside through the underwater acoustic signal. The four-core watertight socket 6 is installed on the outer wall of the glass cabin ball 10 through the cabin, and is connected with the temperature measuring probe 4 through the RS485 bus 7 . The fixed bracket 12 and the coupling bracket 17 are fixed inside the glass cabin ball 10 , and the coupling bracket 17 is installed below the fixed bracket 12 . The data collector 11 is installed above the fixed bracket 12, and the battery pack 14 surrounds the side of the glass cabin ball 10 installed in the middle of the fixed bracket 12 and the coupling bracket 17, and a total of 10 groups of 10AH batteries are placed to ensure continuous operation of the submarine signal acquisition base station 24. more than a month. At the same time, the battery pack 14 is evenly placed in the glass capsule ball 10 to keep the instrument in balance during the sinking process. The outer protective shell 13 is divided into upper and lower parts, and the middle of the two is fixed by a plurality of bolts to protect the inner glass cabin ball 10 and to fix the temperature measuring probe 4 .

The direction sensor 15 and the attitude sensor 16 are fixed above the coupling bracket 17. The direction sensor 15 is used to detect the direction deflection angle of the seabed signal acquisition base station 24. The HMR3200 type direction sensor used adopts the Honeywell magnetoresistive sensor design to achieve small size and high Reliability and accuracy, the accuracy is controlled at 1°, and the resolution is 0.1°. The attitude sensor 16 is used to detect the inclination angle of the seabed signal acquisition base station 24 and the temperature measuring probe 4 relative to the horizontal plane, which is convenient for later calculation of the seabed temperature gradient. The present invention adopts the ADXL345 attitude sensor, which is a digital accelerometer, with a maximum measurable range of ±16g, a maximum resolution of 3.9mg/LSB, and can detect changes in inclination angles lower than 1.0°.

As accompanying drawing 3, the sinking coupling frame 5 that adopts among the present invention is welded by steel material, is coated with antirust coating above. The sinking coupling frame 5 is a square frame, and the middle part is provided with a rigid metal ring 18, and the instrument cabin 2 is placed on the metal ring 18. The square frame is connected with the metal ring 18 through four steel beams, the metal ring, the steel beam, and the square frame of the sinking frame are hollow, and the temperature measuring probe 4 passes through the middle of the metal ring 18 . A diversion cylinder with a diameter of 120mm and a height of 150mm is welded to each of the four corners of the sinking coupling frame, which can guide the seawater during the sinking process of the instrument and keep the instrument in a vertical state during the falling process. Simultaneously, the guide tube is also conducive to the submarine signal acquisition base station 24 not being easily trapped in the seabed mud. A cylindrical guide tube is also welded below the metal ring 18, which is beneficial to ensure the vertical insertion of the temperature measuring probe 4 during insertion into the seabed sediment, and protects the temperature measuring probe 4. After receiving the recovery command, the submarine signal acquisition base station 24 discards the sinking coupling frame 5 through the decoupling mechanism 1, and uses the buoyancy provided by the instrument cabin 2 to realize self-floating recovery.

This implementation example does not show the decoupling mechanism 1 in detail in the accompanying drawings of the description, and its specific structure can be found in the technical information already disclosed by the applicant (patent number: ZL200810117385.4).

As shown in Figure 4, it is a schematic diagram of the cross-sectional structure of the temperature measuring probe 4 in the self-floating seabed temperature detection system. The shell of the temperature measuring probe 4 is made of stainless steel, the main body is cylindrical, 1 to 1.5 meters long, 3 cm in diameter, and 0.5 cm thick. The socket 19; the main body of the temperature measuring probe 4 is provided with a plurality of round holes 23 through which seawater flows freely to ensure that the internal temperature of the temperature measuring probe 4 is consistent with that of the outside. A plurality of temperature detection units 21 are placed inside the temperature measurement probe 4 , and the temperature detection units 21 include a temperature acquisition circuit 22 inside. The temperature detection unit 21 is cylindrical and sealed as a whole. The top and bottom of the cylinder are respectively provided with four-core watertight sockets. The temperature detection units 21 are connected through the RS485 bus 20 . pin 4 inside.

As shown in Figure 5, it is a structural block diagram of the temperature acquisition circuit in the temperature detection unit. The temperature detection unit 21 includes a complete temperature acquisition circuit 22. Considering that the seafloor temperature signal has the characteristics of small variation and many low-frequency changes, it is necessary to focus on the design of the temperature acquisition circuit 22 to obtain reliable seafloor temperature information. The temperature acquisition circuit 22 includes a resistance bridge circuit, an operational amplifier chip AD8553, an analog-to-digital converter chip AD7791, a reference voltage chip MAX6126, a microprocessor chip LPC812, and an RS485 bus chip MAX485. The selected chips all have good low-temperature drift and high-precision characteristics. The present invention uses MAX6126 as the reference voltage chip. The analog-to-digital converter AD7791 provides the reference voltage and supplies power to the resistance bridge circuit at the same time. Using the same reference power supply can eliminate the error caused by the reference voltage drift. The AD8553 is an auto-zero instrumentation amplifier with an offset voltage drift of 0.1μV/°C and a voltage noise of only 0.7μV peak-to-peak (0.01Hz to 10Hz), especially suitable for low frequency signal amplification. AD7791 is a 24-bit high-precision analog-to-digital converter, and the output can vary within the range of 9.5Hz to 120Hz. When the output is 9.5Hz, the effective precision can reach 22bit. The differential signal output by the resistance bridge is amplified by AD8553 and converted to analog by AD7791. Microcontroller LPC812 sends the digital signal after analog to digital conversion to the submarine signal acquisition base station 24 via MAX485 via RS485 bus.

As shown in accompanying drawing 6, it is the signal amplification part circuit in the temperature acquisition circuit. Specifically, resistors R1, R2, R4, and R5 form a resistor bridge network, and the output signals of the resistor bridge are respectively connected to pin 2 and pin 9 of AD8553; one end of resistor R3 is connected to pin 1 of AD8553, and the other end is connected to pin 10 of AD8553 ; One end of resistor R6 is connected with C9 in parallel with pin 4 of AD8553, and the other end is connected with pin 5 of AD8553. High-frequency signal noise, the amplified analog signal is then subjected to analog-to-digital conversion. R3 and R6 are used as AD8553 amplification reference resistors, and the amplification factor can be changed by changing the resistance value. In the present invention, the amplification factor is set to 10 according to the formula 2*R6/R3. In order to reduce circuit noise, low-temperature drift and high-precision thin film resistors are used in the circuit. Specifically, R5 selects the 10K thin film resistor of Susumu Company with the number RG2012L-103-L-T05, the tolerance is 0.01%, and the temperature coefficient is 2ppm/°C; R1 and R2 use the number of Susumu Company RG2012L-102-L- The 1K thin film resistor of T05 has a tolerance of 0.01% and a temperature coefficient of 2ppm/°C; the resistor R3 is a 20K thin film resistor with a Vishay company number PLT0805Z2002AST5, and the resistor R6 is a 100K thin film resistor with a Vishay company number TNPU0805100KAZEN00.

The specific working process of the self-floating seabed temperature detection system is as follows:

1. The survey ship travels to the designated sea area, and conducts status inspection on the self-floating seabed temperature detection system to ensure that the instrument meets the requirements for entering the sea.

2. The self-floating seabed temperature detection system obtains GPS information, and the staff can interactively set the working parameters of the temperature detection unit.

3. Put the self-floating seabed temperature detection system into the water, it sinks into the seabed under the action of gravity and inserts the temperature measuring probe into the seabed sediment. The instrument starts seabed temperature detection, and at the same time, the seabed signal acquisition base station records the attitude information of the instrument.

4. When recovering, the survey ship communicates with the underwater acoustic sensor in the submarine signal acquisition base station through sonar in the sea area where it is launched and sends a recovery command. After the submarine signal acquisition base station received the command, the decoupling mechanism started to work. After about 5 minutes, the steel cable was separated from the submarine signal acquisition base station, and the sinking coupling frame was discarded. The submarine signal acquisition base station and the temperature measuring probe rose to the sea surface together with the buoyancy. Recovered by survey ship.

5. Extract the recorded data for analysis and processing.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone familiar with the technical field can easily think of Changes or substitutions should fall within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (4)

1. A self-floating seabed temperature detection system, which belongs to geophysical measuring instruments, comprises a seabed signal acquisition base station (24) and a temperature measuring probe (4); wherein the seabed signal acquisition base station (24) comprises a decoupling mechanism (1 ), the instrument cabin (2) and the sinking coupling frame (5); the instrument cabin (2) includes an inner single glass cabin ball (10) and an outer protective shell (13); the glass cabin ball (10) is provided with a four-core watertight socket (6), the submarine signal acquisition base station (24) is connected with the temperature measuring probe (4) by a wire (7); the submarine signal acquisition base station (24) is internally integrated with a direction sensor (15) and an attitude sensor (16), for Obtain the inclination condition of the temperature measuring probe inserted into the seabed; the outer protective shell (13) of the glass cabin ball is divided into upper and lower parts, the two are fixed by a plurality of bolts, and the temperature measuring probe (4) is fixed on the outer protective shell (13) by bolts ) bottom; the top of the external protective shell (13) is equipped with a decoupling mechanism (1), and the instrument cabin (2) is placed on the sinking coupling frame (5) as a whole; the sinking coupling frame (5) is a square frame with a rigid metal frame in the middle The circular ring and the square frame are connected with the rigid metal circular ring by four steel beams, the metal circular ring, the steel beam, and the square frame of the sinking coupling frame are hollow, and the temperature measuring probe (4) passes through the middle of the metal circular ring (18) . 2. The self-floating seabed temperature detection system according to claim 1, the temperature measuring probe (4) is vertically fixed on the bottom of the outer protective shell (13) by bolts, the glass cabin ball (10) and the temperature measuring probe ( 4) There are four-core watertight sockets at each end, and the two are connected by RS485 bus (7). The bus is divided into power line, ground line, data line A and data line B; the main body of the temperature measuring probe (4) is cylindrical , 1 to 1.5 meters long, 3 cm in diameter, 0.5 cm in wall thickness, with a conical front end, and a four-core watertight socket at the end of the temperature measuring probe; the main part of the temperature measuring probe (4) is provided with multiple round holes ( 23), seawater can flow freely inside and outside the temperature measuring probe (4). 3. The self-floating seabed temperature detection system according to claim 1 or 2, characterized in that: a plurality of temperature detection units (21) are placed inside the temperature measurement probe (4), and the temperature detection units (21) pass through the RS485 bus (20) connected and placed vertically inside the temperature measuring probe (4); the temperature acquisition circuit (22) integrating the negative temperature coefficient thermistor is placed inside the temperature detection unit (21); the temperature detection unit (21) is cylindrical, Integral sealing, four-core watertight sockets are provided on the top and bottom of the cylinder, which can be connected to the submarine signal acquisition base station (24) alone or multiple serial connections can be connected to the submarine signal acquisition base station (24). Gradient detection; when detecting the seabed temperature gradient, an appropriate length RS485 bus can be selected according to requirements, and the seabed signal acquisition base station (24) communicates and transmits data with the internal temperature detection unit (21) of the temperature measuring probe through the RS485 bus. 4. The self-floating seabed temperature detection system according to claim 2 or 3, characterized in that: the temperature detection unit (21) is internally integrated with a complete temperature acquisition circuit (22), which can directly output digital signals, and the digital signals pass through the RS485 bus It is transmitted to and stored in the seabed signal acquisition base station (24), and the seabed signal acquisition base station (24) controls the working time of the temperature detection unit (21) through the RS485 bus and determines working parameters such as the sampling rate.