Temperature measuring device for deep geothermal well

Abstract

The invention discloses a temperature measuring device for a deep geothermal well, and belongs to the technical field of temperature measurement. Comprising a piston plate, a piston rod, a rocker, a driving pawl, a gear and a counter, the piston plate is connected into the box body in a sealed and sliding mode and divides the box body into an upper cavity and a lower cavity. The lower cavity is filled with inert gas; the top of the piston plate is connected with a piston rod; the long rod part of the rocker is connected with the piston rod through a hook spring; the top end of the end of the rocker is hinged to the driving pawl. The center of the gear is rotationally connected with the box body, and the driving pawl is meshed with the gear; a mechanical counter is directly integrated on a gear, each gear tooth of the gear corresponds to a certain temperature variation, and temperature measurement is achieved by metering the number of revolutions of the gear; the device is suitable for long-term temperature monitoring work in high-temperature severe environments such as geothermal wells and the like, and can effectively prevent measurement errors caused by environmental factors.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of temperature measurement, and relates to temperature measurement in a high-temperature geothermal well. BACKGROUND

[0002] A gas thermometer is a kind of instrument for measuring the temperature of an object by using the thermal expansion and contraction characteristics of rare gas. The existing liquid temperature measurement in a high-temperature geothermal well mainly relies on contact sensors such as thermocouples and platinum resistance, which are prone to material oxidation and signal drift in a high-temperature environment above 300 DEG C, and have poor long-term stability. In addition, corrosive gases such as hydrogen sulfide in the well will accelerate the failure of the sensor, resulting in data deviation. The high pressure in the well, the dynamic fluid environment and electromagnetic interference (such as electromagnetic radiation of the while-drilling equipment) have a significant impact on traditional electronic sensors, and the measurement error in some cases can reach ± 10 DEG C. Therefore, it is of great significance to provide a temperature measurement device and method suitable for deep geothermal wells, which has high temperature resistance, high sensitivity and good accuracy for geothermal development. SUMMARY

[0003] The present application overcomes the shortcomings of the prior art and provides a temperature measurement device for a deep geothermal well.

[0004] The present application is realized by the following technical solutions: A temperature measurement device for a deep geothermal well comprises a piston plate, a piston rod, a rocker, a driving pawl, a gear and a counter. The piston plate is sealingly and slidingly connected in the box, and the piston plate is in a horizontal state. The piston plate divides the box into an upper cavity and a lower cavity. The lower cavity is filled with inert gas. The piston rod is connected to one side of the top of the piston plate. The rocker is located on one side of the piston rod. The rocker comprises a long rod portion and an end head portion connected together. The long rod portion of the rocker is connected to the piston rod through a hook spring. The center of the end head portion of the rocker is rotationally connected to the box. The top end of the end head portion of the rocker is hingedly connected to the driving pawl. The center of the gear is rotationally connected to the box. The driving pawl is engaged with the gear. A mechanical counter is directly integrated on the gear. The counter adopts a worm and gear transmission mechanism to convert the rotary motion of the gear into digital display. Each gear tooth of the gear corresponds to a certain temperature change. The number of revolutions of the gear is measured to realize temperature measurement.

[0005] Further, a first cross rod is provided in the middle of the piston rod and fixedly connected. Hook springs are symmetrically provided on the first cross rod and located on both sides of the piston rod. The hook springs are connected to the first cross rod through a set of spring buckles. Further, a second cross rod is provided in the middle of the long rod portion of the rocker away from the end head portion and fixedly connected. The other ends of the two hook springs away from the piston rod are connected to the second cross rod through another set of spring buckles.

[0006] Further, the support shaft is fixed on the side wall of the box through a large nut, and the end of the rocker is rotatably connected to the support shaft.

[0007] Further, the gear rotating shaft is fixedly connected to the side wall of the box through a medium nut, and the center of the gear is rotatably connected to the gear rotating shaft.

[0008] Further, the anti-reverse pawl is rotatably connected to the box, and is located below the gear and engaged with the gear.

[0009] Further, the center shaft is connected to the side wall of the box through a small nut, and the anti-reverse pawl is rotatably connected to the center shaft.

[0010] Further, a limiting boss is arranged on the side wall of the box, and the limiting boss is located above the piston plate.

[0011] Further, a high-temperature-resistant closed head cover is arranged on the top of the box, and a high-temperature-resistant transparent glass cover is arranged at the middle position of the high-temperature-resistant closed head cover.

[0012] Further, four partitions are arranged in the box, dividing the box into four measuring areas around and a processing area in the middle, and a temperature measuring device is arranged in each of the four measuring areas around to measure the temperature of the four directions in the box.

[0013] The beneficial effects of the present application relative to the prior art are: 1. The present application realizes temperature measurement through the principle of thermal expansion and contraction of gas, and all key components are made of high-temperature-resistant materials, which is particularly suitable for long-term temperature monitoring in high-temperature harsh environments such as geothermal wells. The mechanical transmission design of the high-temperature-resistant shell and the parts in the cavity avoids the failure risk of electronic components in high-temperature environments, and the detachable structure greatly simplifies the maintenance process of the equipment.

[0014] 2. The present application adopts a double pawl structure, which can greatly reduce measurement error and ultimately obtain more accurate temperature data. During the upward lifting process of the temperature measuring device by the operator, the existence of the anti-reverse pawl can effectively prevent the gear from rotating due to the decrease of the temperature of the argon gas in the cavity caused by the external environment, and can effectively prevent measurement error caused by environmental factors.

[0015] 3. The present application considers the natural error of uneven heating of the four heat transfer surfaces, and sets temperature measuring devices on the four heat transfer surfaces to collect heat storage temperature information, and finally uses an intelligent calculator in the central cavity to automatically average the obtained temperature values, which greatly reduces the measurement error and can obtain accurate temperature data. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 Partial box front view cross-section of the temperature measuring device of the present application.

[0017] Figure 2 Partial box left view cross-section of the temperature measuring device of the present application.

[0018] Figure 3 Partial box top view cross-section of the temperature measuring device of the present application.

[0019] Figure 4 Complete box top view cross-section of the temperature measuring device of the present application.

[0020] Figure 5 B-B cross-section of Figure 4 .

[0021] Figure 6 D-D cross-section of Figure 4 .

[0022] Figure: 1, gear; 2, counter; 3, driving pawl; 4, rocker; 5, anti-reverse pawl; 6, piston rod; 7, piston plate; 8, hook spring; 9, limiting boss; 10, spring buckle; 11, medium nut; 12, small nut; 13, large nut; 14, center shaft; 15, gear rotating shaft; 16, support shaft; 19, high-temperature-resistant closed head cover; 20, high-temperature-resistant transparent glass cover; 21, box. DETAILED DESCRIPTION

[0023] In order to make the technical problems to be solved by the present application, technical solutions and beneficial effects more clear and explicit, the present application is further described in detail in combination with embodiments and drawings. It should be understood that the specific embodiments described herein are only used to explain the present application and not used to limit the present application. The technical solutions of the present application are described in detail below in combination with embodiments and drawings, but the protection scope is not limited by this.

[0024] Referring to Figures 1 to 6 , the embodiment proposes a temperature measuring device for deep geothermal well, which adopts mechanical temperature measurement principle, the temperature measuring device is arranged in the box 21, the box 21 itself is made of high-temperature-resistant material, the high-temperature-resistant closed head cover 19 is arranged on the top of the box 21; the high-temperature-resistant transparent glass cover 20 is arranged on the high-temperature-resistant closed head cover 19 at the middle position, the temperature measuring device is carried by the box 21, the internal temperature measuring device is protected by the high-temperature-resistant closed head cover 19, and the temperature measuring device inside the box 21 can be observed through the high-temperature-resistant transparent glass cover 20. In use, the temperature measuring device is directly connected with the high-temperature-resistant closed head cover 19 through the external lifting device, so as to facilitate the movement of the temperature measuring device to the position to be measured in the deep geothermal well.

[0025] The box 21 is internally provided with four partitions, which divide the box 21 into four measuring areas around and a processing area in the middle. One temperature measuring device is installed in each of the four measuring areas. The temperature in the deep geothermal well can be more accurately reflected by measuring the temperature of the four areas in the box 21. The processing area in the middle is used to place a computer for data processing. The computer can collect the geothermal reservoir temperature data from the four measuring areas and automatically average the values to obtain more accurate temperature data of the geothermal reservoir at a certain position. It should be noted that the computer and data processing functions are prior art and will not be described here.

[0026] The temperature measuring device includes a piston plate 7, a piston rod 6, a rocker 4, a driving pawl 3, a gear 1 and a counter 2. A piston plate 7 is slidably connected above the bottom of each of the four measuring areas. The sliding mode between the piston plate 7 and the partition and the side wall of the box 21 can be a track structure or a chute structure, etc. The structure of the sliding mode is prior art, which is to ensure that the piston plate 7 slides smoothly on the bottom of the box 21 without other resistance. A sealing layer is provided on the sliding contact surface between the piston plate 7 and the partition and the side wall of the box 21 to ensure the sealing between the piston plate 7 and the box 21 below. Argon gas is filled in the cavity between the piston plate 7 and the box 21 below.

[0027] A piston rod 6 is connected to one side of the top of the piston plate 7. The piston rod 6 is vertically arranged and slides up and down when the piston plate 7 slides up and down. The mass of the piston rod 6 and the piston plate 7 has a certain relationship with the mass of the argon gas filled in the lower cavity.

[0028] A first cross rod is provided in the middle of the piston rod 6 and fixedly connected. Hook springs 8 are symmetrically provided on the first cross rod and located on both sides of the piston rod 6. The hook springs 8 are connected to the first cross rod by a set of spring buckles 10. The rocker 4 is located on one side of the piston rod 6. The rocker 4 includes a long rod part and a head part connected together. A second cross rod is provided in the middle of the end of the long rod part away from the head part and fixedly connected. The other ends of the two hook springs 8 away from the piston rod 6 are connected to the second cross rod by another set of spring buckles 10. When the piston rod 6 moves up and down, the long rod part of the rocker 4 is pulled by the hook springs 8, and then the head part of the rocker 4 is pulled. When connecting, make sure to take anti-loose measures and install spring washers.

[0029] A support shaft 16 is fixed on the side wall of the box 21 by a large nut 13. The center of the head part of the rocker 4 is rotatably connected to the support shaft 16. The top end of the head part of the rocker 4 is hingedly connected to the driving pawl 3.

[0030] Gear rotating shaft 15 is fixedly connected to the side wall of the box 21 by a medium nut 11; the center of the gear 1 is rotatably connected to the gear rotating shaft 15, and the driving pawl 3 is engaged with the gear 1; the gear 1 can be driven to rotate by the driving pawl 3.

[0031] The gear hole diameter of the gear 1 is smaller than the outer diameter of the gear rotating shaft 15, the gear rotating shaft 15 is a variable diameter shaft, the outer diameter of the shaft at the connection part with the gear 1 is substantially equal to the diameter of the gear hole of the gear 1, when the temperature measuring device is lowered by the lifting device, the gear 1 will not slide forward and backward on the gear rotating shaft 15, but only rotate.

[0032] A high-precision mechanical counter 2 is directly integrated on the gear 1, and when the gear 1 rotates, the counter 2 can more accurately measure the frequency of the meshing teeth passing through. The counter 2 adopts a worm and gear transmission mechanism to convert the rotating motion of the gear 1 into digital display, and each tooth corresponds to a specific temperature change amount, and the number of rotations of the gear 1 is measured to realize accurate temperature measurement. The connection structure of the gear 1 and the counter 2 is prior art, and the principle is as follows: 1)、‌Worm and gear transmission mechanism‌ The worm is coaxially connected with the gear 1, and the rotating motion of the gear 1 is transmitted to the worm through the spiral tooth engagement. This mechanism can realize power transmission between staggered shafts, and has self-locking characteristics, which is suitable for high-precision counting scenes.

[0033] 2)、‌Mechanical counter linkage‌ The output shaft of the worm directly drives the input shaft of the counter 2, and the rotating motion is converted into digital display through a gear train. The typical structure includes: the worm in the worm box drives the upper table plate to rotate (similar to the turnover mechanism of YMZ-1 mold assembly machine); the counter 2 adopts a 7-bit mechanical design, and is linked with the worm shaft through a pulling arm to realize cumulative counting.

[0034] 3)、Temperature-rotation conversion mechanism‌ Each tooth on the gear 1 corresponds to a specific temperature change amount, and the number of rotations of the gear 1 drives the counter 2 after being amplified by the worm and gear mechanism. For example: the Archimedes worm or involute worm can ensure transmission accuracy, and the mechanical counter processes pulse signals through photoelectric coupling or Schmidt trigger.

[0035] The key of this structure is the design of the speed reduction ratio of the worm and gear, which needs to match the corresponding relationship between the number of gear teeth and the temperature range, and at the same time, the non-resettable feature of the mechanical counter is used to ensure data reliability.

[0036] The counters 2 in the four measuring areas are connected to the computer, and the data of the four measuring areas are transmitted to the computer in the central cavity through the sensors, considering the uneven heating of the four heat transfer surfaces, and the counter values obtained by the four cavities are averaged by the computer, and more accurate heat storage data are obtained. The heat storage value can be clearly seen through the high-temperature transparent glass cover 20.

[0037] A central shaft 14 is connected to the side wall of the box 21 through a small nut 12; the central shaft 14 is rotatably connected to an anti-reverse pawl 5; the anti-reverse pawl 5 is located below the gear 1 and engages with the gear 1; when the gear 1 rotates counterclockwise, the anti-reverse pawl 5 will be stuck in the teeth to prevent the gear 1 from rotating counterclockwise; the design requirements of the anti-reverse pawl 5 are consistent with the design requirements of the gear 1 tooth groove and the gear teeth; when the gear 1 rotates clockwise, the gear 1 can drive the anti-reverse pawl 5 to move upward, and after a certain distance, the anti-reverse pawl 5 will enter the next tooth groove. When the gear 1 rotates counterclockwise, the anti-reverse pawl 5 will be stuck in the tooth groove of the gear 1, preventing the gear 1 from rotating counterclockwise.

[0038] Among them, the support shaft 16, the central shaft 14 and the gear shaft 15 all have the characteristics of high temperature and high pressure resistance.

[0039] A limiting boss 9 is also provided on the side wall of the measuring area, and the limiting boss 9 is located above the piston plate 7. When the piston plate 7 moves upward due to the expansion of argon, the limiting boss 9 prevents the piston plate 7 from moving upward too far and colliding with the rocker 4, causing temperature measurement failure. The limiting boss 9 is designed according to the maximum distance of upward movement of the piston plate 7 at different temperatures during the experiment, and the height of the limiting boss 9 is set as high as possible without affecting the normal temperature measurement of the device.

[0040] The working principle of the temperature measuring device for deep geothermal wells proposed in the embodiment is as follows: 1) When using the device to measure temperature, first, the upper cavity between the piston plate 7 and the upper box 21 is evacuated, and then an external lifting device is used to lower the temperature measuring device to the measured position of the deep geothermal well for temperature measurement. 2), when measuring temperature, according to the gas state equation PV = NRT, when the pressure is constant, the volume of the gas changes with the change of temperature, that is, the argon gas in the lower cavity will change the volume V due to the thermal expansion and contraction characteristics, as the temperature measuring device is lowered to the measured position under the operation of the lifting device, the temperature in the lower cavity will gradually rise, the piston plate 7 will gradually move up, the piston rod 6 drives the rocker 4 to move, the rocker 4 in turn drives the driving pawl 3 to move, the driving pawl 3 is engaged with the gear 1, then the driving pawl 3 will push the gear 1 to rotate clockwise, when the gear 1 rotates, the counter 2 installed on the gear 1 gear teeth will record the number of rotations of the gear 1 in real time, finally the data of the counter 2 is converted into temperature data to obtain the temperature of the liquid to be measured in the high temperature geothermal well.

[0041] 3), when the temperature measuring device rises to the wellhead under the operation of the lifting device, the temperature in the lower cavity will gradually decrease, the piston plate 7 will gradually move down, and finally the gear 1 will rotate under the mechanical cooperation of the cavity piston rod 6, the rocker 4 and the driving pawl 3, which will cause the gear to rotate, resulting in the scrap of the final measurement data, the design of the anti-reverse pawl 5 will make the gear rotation phenomenon not occur under any circumstances, when measuring temperature, the anti-reverse pawl 5 will not affect the driving pawl 3 to push the gear 1 to rotate clockwise. The limiting boss 9 will ensure that the gas thermometer will not fail in mechanical movement during temperature measurement, so as to ensure that the gas thermometer can continuously measure temperature.

[0042] Considering the natural error of uneven heating of the four heat transfer surfaces, temperature measuring devices are arranged on the four heat transfer surfaces, and a computer is arranged in the central inner cavity. The counter values obtained from the four inner cavities can be averaged, and the heat storage value can be clearly seen through the high-temperature transparent glass cover 20. The measurement error is greatly reduced, and relatively accurate temperature data can be obtained.

[0043] In order to quickly obtain the temperature data of the liquid to be measured in the high temperature geothermal well, the corresponding number of gear rotations corresponding to the temperature can be obtained in advance through experiments in the laboratory, and a table is drawn, and the temperature data of the liquid to be measured is directly obtained by looking up the table after temperature measurement. The data displayed by the counter 2 is used to look up the table (the table is obtained by using experimental method on the ground to accurately convert the number of gear rotations at different temperatures into temperature data), and the two are compared, and finally the relatively accurate temperature of the liquid in the high temperature geothermal well can be obtained.

[0044] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting; it is not intended to exclude myriad other embodiments of the present application that other inventors can develop based on the same general inventive concepts embodied by the described embodiments. That is, although the present application is described in terms of particular embodiments and implementations, it is to be understood that the terminology used is for the purpose of descriptive clarity and that it should be taken in its broadest possible sense. For example, the terms "a", "an", and "the" include both singular and plural referents unless the context clearly dictates otherwise. The terms "comprises", "comprising", "includes", "including" and the like can be used in conjunction with the term "consisting of to include the elements or steps listed after such conjunctive language, but not to the exclusion of other elements or steps. The singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise.

[0045] While the embodiments of the application have been shown and described herein, it is to be understood that the application is not limited to these embodiments. Rather, many modifications, changes and substitutions are intended to fall within the scope of the present application, which is limited only by the scope of the claims hereinafter appended.

Claims

1. A temperature measuring device for deep geothermal wells, characterized in that, The assembly includes a piston plate (7), a piston rod (6), a rocker arm (4), a drive pawl (3), a gear (1), and a counter (2). The piston plate (7) is slidably connected to the housing (21) and is in a horizontal state. The piston plate (7) divides the housing (21) into an upper chamber and a lower chamber. The lower chamber is filled with inert gas. The piston rod (6) is connected to one side of the top of the piston plate (7). The rocker arm (4) is located on one side of the piston rod (6). The rocker arm (4) includes a long rod and an end head connected together. The long rod of the rocker arm (4) is connected to the piston rod (6) by means of a... The hook spring (8) is connected; the center of the end of the rocker arm (4) is rotatably connected to the housing (21), and the top of the end of the rocker arm (4) is hinged to the drive pawl (3); the center of the gear (1) is rotatably connected to the housing (21), and the drive pawl (3) meshes with the gear (1); a mechanical counter (2) is directly integrated on the gear (1), and the counter (2) adopts a worm gear transmission mechanism to convert the rotational motion of the gear (1) into a digital display. Each tooth of the gear (1) corresponds to a certain amount of temperature change, and temperature measurement is achieved by measuring the number of revolutions of the gear (1).

2. The temperature measuring device for deep geothermal wells according to claim 1, characterized in that, A first crossbar is inserted through and fixedly connected to the piston rod (6). Hook springs (8) are symmetrically arranged on the first crossbar and on both sides of the piston rod (6). The hook springs (8) are connected to the first crossbar through a set of spring clips (10).

3. The temperature measuring device for deep geothermal wells according to claim 2, characterized in that, A second crossbar is inserted and fixedly connected to the middle of the long rod of the rocker arm (4) away from the end head. The other ends of the two hook springs (8) away from the piston rod (6) are connected to the second crossbar through another set of spring clips (10).

4. The temperature measuring device for deep geothermal wells according to claim 1, characterized in that, A support shaft (16) is fixed on the side wall of the housing (21) by a large nut (13), and the center of the end of the rocker arm (4) is rotatably connected to the support shaft (16).

5. A temperature measuring device for deep geothermal wells according to claim 1, characterized in that, A gear shaft (15) is fixedly connected to the side wall of the housing (21) by a medium nut (11); the center of the gear (1) is rotatably connected to the gear shaft (15).

6. A temperature measuring device for deep geothermal wells according to claim 1, characterized in that, It also includes an anti-reverse pawl (5), which is rotatably connected to the housing (21). The anti-reverse pawl (5) is located on the underside of the gear (1) and meshes with the gear (1).

7. A temperature measuring device for deep geothermal wells according to claim 6, characterized in that, A central shaft (14) is connected to the side wall of the housing (21) by a small nut (12); the anti-reverse pawl (5) is rotatably connected to the central shaft (14).

8. A temperature measuring device for deep geothermal wells according to claim 1, characterized in that, A limiting boss (9) is also provided on the side wall of the housing (21), and the limiting boss (9) is located above the piston plate (7).

9. A temperature measuring device for deep geothermal wells according to claim 1, characterized in that, The top of the box (21) is provided with a high temperature resistant sealed cover (19); a high temperature resistant transparent glass cover (20) is provided in the middle of the high temperature resistant sealed cover (19).

10. A temperature measuring device for deep geothermal wells according to any one of claims 1-9, characterized in that, The box (21) is equipped with four partitions, which divide the inside of the box (21) into four measurement areas around the perimeter and a processing area in the middle. A temperature measuring device is installed in each of the four measurement areas around the perimeter to measure the temperature of the four areas inside the box (21). The processing area in the middle is used to place a computer for data processing. The data of the counters (2) in the four measurement areas are transmitted to the computer through the sensors.

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