Pressure type temperature measuring equipment

Abstract

The invention discloses pressure type temperature measuring equipment which comprises a pressure transmitter, the lower end of the pressure transmitter is provided with an installation thread, the outer wall of the installation thread is provided with a positioning nut and a connecting nut, the lower end of the connecting nut is provided with a connecting block, and the lower end of the connecting block is provided with a pressure detection pipe. When the pressure type temperature measurement equipment is used, the connection sealing performance of the pressure detection pipe and the pressure transmitter is absolutely reliable through the installation mode of the pressure transmitter and the pressure detection pipe, and the material type selection of the pressure detection pipe and the manufacturing of the diameter and the length of the pipe are reasonably carried out according to a single gas and then in a closed space; the filling gas can be fully heated and expanded, 99.9% nitrogen and the filling pressure are utilized to effectively reflect the temperature change of the measured medium and the principle that the volume is linearly expanded along with the temperature rise, and the practicability is higher.

Description

Technical Field

[0001] The invention relates to the technical field of pressure-type temperature measuring equipment, in particular to a pressure-type temperature measuring equipment. Background Art

[0002] The pressure-type temperature measurement equipment is a device that measures temperature based on the changing relationship between the saturated vapor pressure and temperature of the evaporating liquid in a closed temperature measurement system. When in use, such as the coke oven gas production and operation of the Chifeng Qinfeng Chemical Project, the first-level hydrogenation reactor is designed to detect the temperature with a PT100 thermistor. According to the design and use conditions, the temperature measurement range of the PT100 thermistor should be 0-500℃. According to the characteristics of the PT100 thermistor, it should be able to meet the actual use needs of the equipment. A total of 18 PT100 thermistor temperature measuring elements are designed for the first-level hydrogenation reactor and the pre-hydrogenation reactor. However, during the actual operation of the production unit, multiple PT100 thermistor measuring elements at the same measuring point and the same equipment deteriorated and could not be used, seriously affecting the stable operation of the production unit.

[0003] Currently, most pressure-type temperature measurement devices are disposable. Once the pressure tube is damaged, the device can no longer be used. The cost of repurchasing and installing the equipment will increase. The substitutability of equipment components is poor, and damaged components cannot be repaired and replaced efficiently.

[0004] Therefore, we propose a pressure-type temperature measurement device to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a pressure-type temperature measuring device. When using the pressure-type temperature measuring device, the connection sealing between the pressure detecting tube and the transmitter is absolutely reliable through the installation method of the pressure transmitter and the pressure detecting tube. In addition, based on a single gas in a closed space, the material selection, pipe diameter and length of the pressure detecting tube are reasonably carried out so that the filling gas can fully expand due to heat. By utilizing 99.9% nitrogen and the filling pressure, the temperature change of the measured medium can be effectively reflected. The principle of linear volume expansion with increasing temperature is adopted, and the practicality is stronger to solve the problems raised in the above-mentioned background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A device for measuring temperature by pressure type comprises a pressure transmitter, wherein the lower end of the pressure transmitter is provided with a mounting thread, and a positioning nut and a connecting nut are respectively provided on the outer wall of the mounting thread, a connecting block is installed at the lower end of the connecting nut, and a pressure detection tube is provided at the lower end of the connecting block.

[0008] In a further embodiment, the pressure detection tube is made of stainless steel, and argon arc welding is used at the joint between the pressure detection tube and the connecting block.

[0009] In a further embodiment, the experimental medium of the pressure detection tube is water, and the filling gas is nitrogen, and a thin hose is inserted into the bottom of the pressure detection tube and filled slowly.

[0010] In a further embodiment, the connecting nut thread is installed on the mounting thread, and a sealant is applied at the mounting location.

[0011] In a further embodiment, the pressure transmitter is provided with a back plate, a threaded hole is provided on the back plate, a mounting block is threadedly connected to the threaded hole, and a threaded cylinder and a telescopic rod are respectively provided on the mounting block.

[0012] In a further embodiment, the inner wall of the threaded barrel is threadedly connected with a threaded rod, one end of the threaded rod is mounted with a rotating shaft, and the rotating shaft is movably embedded in the inner wall of the connecting plate.

[0013] In a further embodiment, a strong suction cup is provided at one end of the connecting plate, and is fixedly connected to the telescopic rod at the lower end of the connecting plate.

[0014] In a further embodiment, a twist nut is installed at the middle end of the outer wall of the threaded rod.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. When using the pressure-type temperature measurement equipment, the installation method of the pressure transmitter and the pressure detection tube makes the connection sealing between the pressure detection tube and the transmitter absolutely reliable. In addition, based on the single gas in a closed space, the material selection, pipe diameter and length of the pressure detection tube are reasonably made, so that the filling gas can fully expand due to heat. By using 99.9% nitrogen and the filling pressure, the temperature change of the measured medium can be effectively reflected. The principle of linear volume expansion with the increase of temperature is more practical.

[0017] Second, the device using the pressure-type temperature measurement is provided with a threaded hole on the back panel, and an adjustable strong suction cup can be installed when in use, which is adsorbed on a flat object to fix the pressure transmitter, and is used in conjunction with a pressure detection tube to assist in use, making it more convenient to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of a pressure-type temperature measurement device;

[0019] Figure 2 It is a structural schematic diagram of a self-locking shaft of a pressure-type temperature measuring device;

[0020] Figure 3 A pressure-type temperature measuring device Figure 2 The enlarged structural diagram at A in the middle;

[0021] Figure 4 This is a schematic diagram of the side view of the limit plate of a pressure-type temperature measurement device.

[0022] In the figure: 1. Pressure transmitter; 2. Mounting thread; 3. Positioning nut; 4. Connecting nut; 5. Connecting block; 6. Pressure detection tube; 7. Back plate; 8. Threaded hole; 9. Mounting block; 10. Threaded barrel; 11. Threaded rod; 12. Twist nut; 13. Rotating shaft; 14. Connecting plate; 15. Strong suction cup; 16. Telescopic rod. DETAILED DESCRIPTION

[0023] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0024] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] See also Figure 1-4 A pressure type temperature measuring device includes a pressure transmitter 1, which is an existing EJA transmitter model EJA110E-JFS5J-912DA, with an effective detection pressure of 0-5Kpa, a threaded connection, an accuracy level of 0.075%, a damping time of 1 second, and a linear output. The pressure detection tube 6 is made of 304s stainless steel and has a diameter of 6mm. When installing, a mounting thread 2 is provided at the lower end of the pressure transmitter 1, and the mounting screw is fixed to the fixed The positioning nut 3 and the connecting nut 4 are provided, and the installation thread 2 is divided into two sections, the upper and lower sections, which are opposite to each other, so that the positioning nut 3 and the connecting nut 4 are also opposite to each other when they are rotated, wherein the positioning nut 3 can be rotated on the installation thread 2 at will, and after the connecting nut 4 is installed, the positioning nut 3 is rotated and fitted on the connecting nut 4 to form a double nut structure, specifically, the positioning nut 3 and the connecting nut 4 are fitted after rotating in opposite directions to prevent the nuts from loosening. Here, in order to prevent the connecting nut 4 from loosening, a connecting block 5 is installed at the lower end of the connecting nut 4, and the connecting block 5 is directly connected to the pressure detection tube 6;

[0027] When installing the pressure detection tube 6, argon arc welding is used at the joint. The welding process should be well protected to ensure that the connecting thread is not damaged by welding. The other side of the pressure detection tube 6 is processed by an arc machine, and argon arc welding is used for welding after polishing. The smoothness of the pipeline must be ensured during welding;

[0028] After the pressure detection tube 6 is installed on the pressure transmitter 1 through the connecting block 5 and the connecting nut 4, a test is carried out. The experimental medium is water, the test pressure is 5Mpa, the pressure maintenance time is 30 minutes, and the pressure loss is not less than 0.005Mpa to be qualified. The filling gas is selected as 99.9% nitrogen, and its volume expansion is 0.00131 / ℃. The volume expansion degree of nitrogen with the increase of temperature is directly related to its expansion coefficient, which is about 0.13% for every increase of 1 degree Celsius. In order to ensure that the gas can fill the pressure detection tube 6, the filling method uses a thin hose to insert the bottom of the measuring tube, and fill it slowly at a flow rate of 0.005ml / min, and then place a match at the outlet to ignite it until the flame goes out and cannot be ignited again. The filling is complete;

[0029] When the pressure detection tube 6 after filling is connected to the pressure transmitter 1, it must be installed vertically to prevent nitrogen from flowing out. Sealant should be applied to the threaded connection, i.e. the positioning nut 3 and the connecting nut 4, to ensure the reliability of the seal. After tightening the threaded connection, the pressure transmitter is tested with power on. At this time, the transmitter should have a pressure value. The reason is that when the connecting thread is tightened again, the excess gas at the connection cannot be discharged and is fastened in the detection tube, forming a positive pressure. At this time, the equipment should be placed still for 24 hours to observe whether the pressure value changes. At the same time, check whether the sealing of the connection is qualified. After 24 hours, the pressure value should not change, which is considered to be qualified. If the pressure value decreases, it needs to be refilled and assembled;

[0030] To assemble qualified pressure-type temperature detection equipment, the pressure transmitter must be cleared first to make it in the zero state, and its lower pressure limit value must be recorded. The assembled pressure-type temperature detection equipment must be installed in 200℃, 300℃, and 400℃ environments in stages, and the corresponding pressure values ​​must be recorded respectively. After calculating the linear first-order equation, the corresponding pressure value at 600℃ is obtained, and this pressure value is used as the upper pressure limit value of the pressure transmitter. At this point, the corresponding work between the pressure transmitter and the pressure change of 99.9% nitrogen with temperature is completed;

[0031] During the use stage, when the pressure detection tube 6 is connected to the pressure transmitter 1, it is necessary to ensure that it is installed vertically. For this purpose, a strong suction cup 15 can be connected externally through the threaded hole 8 set on the back plate 7 of the pressure transmitter 1, and the pressure transmitter 1 is placed at a high place in a vertical state with the pressure detection tube 6. The strong suction cup 15 can be any suction cup with strong suction in reality, and the pressure transmitter 1 can be adsorbed and installed on a plane. Specifically, when in use, the set strong suction cup 15 is installed through the connecting plate 14, and when the connecting plate 14 is installed, first, a telescopic rod 16 and a threaded rod 11 are arranged on the upper and lower sides, and the outer wall of the threaded rod 11 is threadedly connected to the threaded cylinder 10, and a mounting block 9 is installed on one side of the threaded cylinder 10 and the telescopic rod 16, and the mounting block 9 can be threadedly connected by bolts On the threaded hole 8, a strong suction cup 15 is installed on the pressure transmitter 1. After the strong suction cup 15 is adsorbed on a device or wall with a flat surface, the pressure transmitter 1 is fixed. After it is fixed, the threaded rod 11 can be driven to rotate on the threaded tube 10 by turning the twist nut 12. When the threaded rod 11 rotates, a rotating shaft 13 is also provided on the other side. The rotating shaft 13 is embedded and installed on the connecting plate 14, so that the threaded rod 11 can rotate smoothly. Therefore, the threaded rod 11 connected by thread can adjust the distance between the back plate 7 and the strong suction cup 15 after the threaded tube 10 rotates. The telescopic rod 16 set during adjustment will also be telescoped to adjust the position of the pressure transmitter 1, so that the display screen position of the pressure transmitter 1 is easy to observe and more convenient to use.

[0032] The working principle of the present invention is as follows: as shown in the figure, it includes a pressure transmitter 1, which is an existing EJA transmitter model EJA110E-JFS5J-912DA, with an effective detection pressure of 0-5Kpa, a threaded connection, an accuracy level of 0.075%, a damping time of 1 second, and a linear output. The pressure detection tube 6 is made of 304s stainless steel and a 6mm diameter stainless steel tube. When installing, a mounting thread 2 is provided at the lower end of the pressure transmitter 1, and the mounting screw is fixed to the fixed The positioning nut 3 and the connecting nut 4 are provided, and the installation thread 2 is divided into two sections, the upper and lower sections, which are opposite to each other, so that the positioning nut 3 and the connecting nut 4 are also opposite to each other when they are rotated, wherein the positioning nut 3 can be rotated on the installation thread 2 at will, and after the connecting nut 4 is installed, the positioning nut 3 is rotated and fitted on the connecting nut 4 to form a double nut structure, specifically, the positioning nut 3 and the connecting nut 4 are fitted after rotating in opposite directions to prevent the nuts from loosening. Here, in order to prevent the connecting nut 4 from loosening, a connecting block 5 is installed at the lower end of the connecting nut 4, and the connecting block 5 is directly connected to the pressure detection tube 6;

[0033] When installing the pressure detection tube 6, argon arc welding is used at the joint. The welding process should be well protected to ensure that the connecting thread is not damaged by welding. The other side of the pressure detection tube 6 is processed by an arc machine, and argon arc welding is used for welding after polishing. The smoothness of the pipeline must be ensured during welding;

[0034] After the pressure detection tube 6 is installed on the pressure transmitter 1 through the connecting block 5 and the connecting nut 4, a test is carried out. The experimental medium is water, the test pressure is 5Mpa, the pressure maintenance time is 30 minutes, and the pressure loss is not less than 0.005Mpa to be qualified. The filling gas is selected as 99.9% nitrogen, and its volume expansion is 0.00131 / ℃. The volume expansion degree of nitrogen with the increase of temperature is directly related to its expansion coefficient, which is about 0.13% for every increase of 1 degree Celsius. In order to ensure that the gas can fill the pressure detection tube 6, the filling method uses a thin hose to insert the bottom of the measuring tube, and fill it slowly at a flow rate of 0.005ml / min, and then place a match at the outlet to ignite it until the flame goes out and cannot be ignited again. The filling is complete;

[0035] When the pressure detection tube 6 after filling is connected to the pressure transmitter 1, it must be installed vertically to prevent nitrogen from flowing out. Sealant should be applied to the threaded connection, i.e. the positioning nut 3 and the connecting nut 4, to ensure the reliability of the seal. After tightening the threaded connection, the pressure transmitter is tested with power on. At this time, the transmitter should have a pressure value. The reason is that when the connecting thread is tightened again, the excess gas at the connection cannot be discharged and is fastened in the detection tube, forming a positive pressure. At this time, the equipment should be placed still for 24 hours to observe whether the pressure value changes. At the same time, check whether the sealing of the connection is qualified. After 24 hours, the pressure value should not change, which is considered to be qualified. If the pressure value decreases, it needs to be refilled and assembled;

[0036] To assemble qualified pressure-type temperature detection equipment, the pressure transmitter must be cleared first to make it in the zero state, and its lower pressure limit value must be recorded. The assembled pressure-type temperature detection equipment must be installed in 200℃, 300℃, and 400℃ environments in stages, and the corresponding pressure values ​​must be recorded respectively. After calculating the linear first-order equation, the corresponding pressure value at 600℃ is obtained, and this pressure value is used as the upper pressure limit value of the pressure transmitter. At this point, the corresponding work between the pressure transmitter and the pressure change of 99.9% nitrogen with temperature is completed;

[0037] During the use stage, when the pressure detection tube 6 is connected to the pressure transmitter 1, it is necessary to ensure that it is installed vertically. For this purpose, a strong suction cup 15 can be connected externally through the threaded hole 8 set on the back plate 7 of the pressure transmitter 1, and the pressure transmitter 1 is placed at a high place in a vertical state with the pressure detection tube 6. The strong suction cup 15 can be any suction cup with strong suction in reality, and the pressure transmitter 1 can be adsorbed and installed on a plane. Specifically, when in use, the set strong suction cup 15 is installed through the connecting plate 14, and when the connecting plate 14 is installed, first, a telescopic rod 16 and a threaded rod 11 are arranged on the upper and lower sides, and the outer wall of the threaded rod 11 is threadedly connected to the threaded cylinder 10, and a mounting block 9 is installed on one side of the threaded cylinder 10 and the telescopic rod 16, and the mounting block 9 can be threadedly connected by bolts On the threaded hole 8, a strong suction cup 15 is installed on the pressure transmitter 1. After the strong suction cup 15 is adsorbed on a device or wall with a flat surface, the pressure transmitter 1 is fixed. After it is fixed, the threaded rod 11 can be driven to rotate on the threaded tube 10 by turning the twist nut 12. When the threaded rod 11 rotates, a rotating shaft 13 is also provided on the other side. The rotating shaft 13 is embedded and installed on the connecting plate 14, so that the threaded rod 11 can rotate smoothly. Therefore, the threaded rod 11 connected by thread can adjust the distance between the back plate 7 and the strong suction cup 15 after the threaded tube 10 rotates. The telescopic rod 16 set during adjustment will also be telescoped to adjust the position of the pressure transmitter 1, so that the display screen position of the pressure transmitter 1 is easy to observe and more convenient to use.

[0038] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0039] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A device for measuring temperature by pressure, comprising a pressure transmitter (1), characterized in that: The pressure transmitter (1) is provided with a mounting thread (2) at the lower end, and a positioning nut (3) and a connecting nut (4) are respectively provided on the outer wall of the mounting thread (2), a connecting block (5) is installed at the lower end of the connecting nut (4), and a pressure detection tube (6) is provided at the lower end of the connecting block (5).

2. The pressure-type temperature measuring device according to claim 1, characterized in that: The material of the pressure detection tube (6) is 304s stainless steel, and argon arc welding is used at the joint between the pressure detection tube (6) and the connection block (5).

3. A pressure-type temperature measuring device according to any one of claims 1-2, characterized in that: The experimental medium of the pressure detection tube (6) is water, and the gas filled is nitrogen. A thin hose is inserted into the bottom of the pressure detection tube (6) and filled slowly.

4. The device for measuring temperature by pressure according to claim 1, characterized in that: The connecting nut (4) is threadedly mounted on the mounting thread (2), and a sealant is applied at the mounting location.

5. The pressure-type temperature measuring device according to claim 1, characterized in that: The pressure transmitter (1) is provided with a back plate (7) having a threaded hole (8) on it, a mounting block (9) being threadedly connected to the threaded hole (8), and a threaded cylinder (10) and a telescopic rod (16) are respectively provided on the mounting block (9).

6. The pressure-type temperature measuring device according to claim 5, characterized in that: The inner wall of the threaded cylinder (10) is threadedly connected to a threaded rod (11), one end of the threaded rod (11) is mounted with a rotating shaft (13), and the rotating shaft (13) is movably embedded in the inner wall of the connecting plate (14).

7. The pressure-type temperature measuring device according to claim 6, characterized in that: A strong suction cup (15) is provided at one end of the connecting plate (14), and is fixedly connected to a telescopic rod (16) at the lower end of the connecting plate (14).

8. The pressure-type temperature measuring device according to claim 6, characterized in that: A twist nut (12) is installed at the middle end of the outer wall of the threaded rod (11).

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