A thermometer with large aspect ratio based on elastic support ring

Abstract

The present invention belongs to the field of temperature measurement technology, and specifically relates to a thermometer with a large aspect ratio based on an elastic support ring, comprising: a protective tube, a thermometer electrical interface, a thermometer installation interface, an elastic support ring, an armored cable and a thermometer probe; the thermometer probe is arranged in the inner cavity of the protective tube, the free end of the thermometer probe is in close contact with the bottom end of the inner cavity of the protective tube, the other end of the thermometer probe is fixedly connected to one end of the armored cable, the other end of the armored cable is fixedly connected to one end of the thermometer electrical interface, and the thermometer installation interface is fixedly connected to the open end of the protective tube; the elastic support ring is sleeved on the armored cable, the elastic support ring comprises an upper sleeve ring, a lower sleeve ring and a plurality of side strips, the plurality of side strips are evenly spaced between the upper sleeve ring and the lower sleeve ring, the two ends of each side strip are respectively fixedly connected to the upper sleeve ring and the lower sleeve ring, and the side strips are bendable elastic structures. The thermometer of the present invention is vibration-resistant and easy to disassemble, and can effectively cope with harsh environments.

Description

Technical Field

[0001] The invention belongs to the technical field of temperature measurement, and in particular relates to a thermometer with a large aspect ratio based on an elastic support ring. Background Art

[0002] In industrial applications, thermometers are widely used to measure the temperature parameters of internal media such as process system pipelines and containers. However, when using thermometers to measure the temperature of fluid media inside certain large-volume containers or pipelines with high operating pressures. In order to ensure the accuracy of temperature measurement, a longer thermometer is required to be effectively inserted into the interior. Depending on the different process system conditions, the insertion depth of some thermometers can reach 0.5 meters or even more than 1 meter. The design length of the thermometer exceeds the length of the thermometer in general industrial applications. At the same time, in order to improve the measurement sensitivity of the thermometer, the diameter of the thermometer probe is usually designed to be thinner, which is conducive to accelerating the conduction of temperature, and the thermometer has a shorter response time and higher sensitivity.

[0003] In the above industrial applications, in order to protect the thermometer body and avoid direct contact between the thermometer and the measured medium, a special thermometer protection tube is generally designed. The protection tube is usually welded on the wall of the container or pipeline, and the thermometer is installed in the protection tube. The medium temperature is transmitted to the thermometer through the protection tube, and the medium temperature is indirectly measured by measuring the wall temperature at the end of the protection tube. In order to ensure that the measurement accuracy and response time meet the requirements, the thermometer probe with a temperature sensing element such as a PT100 resistance wire needs to be in close contact with the end of the protection tube, and no looseness or obvious gap is allowed.

[0004] In practical applications, because the thermometer and its protective tube are long and placed in high-temperature, high-pressure fluid, the protective tube has a certain degree of vibration. With the long-term operation of the process system, coupled with the gravity of the thermometer itself, it is easy to cause the thermometer armored cable to bend and deform, which in turn causes the thermometer probe to be unable to fit tightly against the wall of the thermometer protection tube, affecting the measurement accuracy and response time. In some cases, the long-term vibration caused by fluid scouring may even cause the internal core wire of the thermometer to break, affecting the safe and stable operation and maintenance of the thermometer. Therefore, it is necessary to add a support ring in the middle of the thermometer to constrain the thermometer armored cable to ensure that the thermometer will not deform during long-term operation, while reducing the impact of the vibration caused by the fluid on the thermometer.

[0005] Take the primary circuit thermometer of a nuclear power plant as an example. The thermometer is more than 0.5 meters long and less than 4 millimeters in diameter. In order to protect the thermometer, a protective tube is designed for the thermometer. At the same time, in order to provide support for the thermometer and prevent the thermometer from vibrating due to the influence of the fluid, solid metal support rings are designed in sections on the thermometer. When the unit is running at full power, the medium temperature measured by the thermometer exceeds 300 degrees Celsius and the medium pressure exceeds 15 MPa.

[0006] However, in this high temperature and high pressure environment, after the thermometer has been running for a long time, due to the small diameter of the thermometer probe and armored cable, the middle support ring of the thermometer is close to the inner wall of the protection tube, and the assembly gap is small. The thermometer protection tube is deformed due to long-term high pressure, resulting in a smaller inner diameter of the protection tube, and the thermometer support ring is stuck. The thermometer cannot be pulled out or the thermometer is disconnected. In addition, the thermometer is located in the containment plant, where the radiation dose is high, and maintenance personnel should not carry out maintenance work for a long time.

[0007] Therefore, it is extremely important to design a thermometer with high accuracy and sensitivity, vibration resistance, and easy disassembly to reduce the failure rate of the thermometer and improve the work efficiency of maintenance personnel. Summary of the invention

[0008] The purpose of the present invention is to provide a thermometer with a large aspect ratio based on an elastic support ring. The thermometer has a long length and a small diameter. The armored cable installed in a protective tube is supported by a new elastic support ring. The thermometer is vibration-resistant and easy to disassemble. It can effectively cope with harsh environments such as large insertion depth, high temperature, high pressure and flow-induced vibration, ensure temperature measurement accuracy and response time, reduce the failure rate of the thermometer, and improve the work efficiency of maintenance personnel.

[0009] A technical solution for achieving the purpose of the present invention: a large aspect ratio thermometer based on an elastic support ring, the thermometer comprising: a thermometer body, a protective tube, a thermometer electrical interface, a thermometer mounting interface and an elastic support ring, the thermometer body comprising an armored cable and a thermometer probe; the thermometer probe is arranged in the inner cavity of the protective tube, the free end of the thermometer probe is tightly attached to the bottom end of the inner cavity of the protective tube, the other end of the thermometer probe is fixedly connected to one end of the armored cable, the other end of the armored cable is fixedly connected to one end of the thermometer electrical interface, and the thermometer mounting interface is fixedly connected to the open end of the protective tube; the elastic support ring is sleeved on the armored cable, the elastic support ring comprises an upper sleeve ring, a lower sleeve ring and a plurality of side strips, the plurality of side strips are equidistantly arranged between the upper sleeve ring and the lower sleeve ring, the two ends of each side strip are respectively fixedly connected to the upper sleeve ring and the lower sleeve ring, and the side strips are bendable elastic structures.

[0010] Furthermore, when the elastic support ring is in a free state, the maximum spherical diameter of the elastic support ring is greater than the diameter of the cavity of the thermometer protection tube.

[0011] Furthermore, the upper sleeve ring of the elastic support ring is fixedly connected to the armored cable, and the lower sleeve ring of the elastic support ring is slidably connected to the armored cable.

[0012] Furthermore, the upper sleeve ring of the elastic support ring is fixedly connected to the armored cable through mechanical extrusion of the thermometer installation interface.

[0013] Furthermore, the elastic support ring is an ellipsoidal lantern structure.

[0014] Furthermore, the elastic support ring is made of a metal material with high yield strength.

[0015] Furthermore, a hole groove is opened at the center of the bottom end of the inner cavity of the protection tube, and the thermometer probe is arranged in the hole groove, and the free end of the thermometer probe is in close contact with the bottom end of the hole groove.

[0016] Furthermore, the diameter of the hole groove is the same as the diameter of the thermometer probe, and the depth of the hole groove is greater than the length of the thermometer probe.

[0017] Furthermore, the thermometer installation interface is fixedly connected to the cavity of the protection tube via threads.

[0018] The beneficial technical effects of the present invention are:

[0019] 1. The present invention provides a thermometer with a large aspect ratio based on an elastic support ring. By setting the side strip of the elastic support ring as a bendable elastic structure, the elastic support ring can maintain contact with the inner wall of the thermometer protection tube in real time, and has a good elastic damping effect. It can effectively reduce the vibration of the thermometer caused by fluid or mechanical operation, and effectively reduce the failure rate of the thermometer.

[0020] 2. The present invention provides a thermometer with a large aspect ratio based on an elastic support ring. By setting the side strip of the elastic support ring as a bendable elastic structure, the elastic support ring can maintain contact with the inner wall of the thermometer protection tube in real time. The elastic support ring will not be affected by the deformation of the protection tube, and will not change the assembly gap between the sleeve and the thermometer support ring. The thermometer is easy to plug and unplug and convenient to assemble and disassemble.

[0021] 3. The present invention is a thermometer with a large aspect ratio based on an elastic support ring. By setting the edge strip of the elastic support ring as a bendable elastic structure, the elastic support ring can maintain contact with the inner wall of the thermometer protection tube in real time, thereby achieving effective support for the armored cable installed in the protection tube. Therefore, an armored cable with a smaller diameter can be used, which is conducive to reducing the mass of the armored cable, thereby reducing the vibration of the armored cable itself, and adapting to harsh use environments such as high temperature, high pressure and flow-induced vibration. At the same time, the use of armored cables with a smaller diameter is conducive to reducing the manufacturing difficulty and production cost of the thermometer;

[0022] 4. The thermometer with a large aspect ratio based on an elastic support ring of the present invention can use a temperature probe with a smaller diameter by effectively supporting the armored cable installed in the protective tube, which can effectively improve the measurement accuracy and accelerate the response time;

[0023] 5. The thermometer with a large aspect ratio based on an elastic support ring of the present invention has a simple structure and can be designed to be longer in length as needed. It can be widely used in process systems with large volumes and requiring a large insertion depth of the thermometer, and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic structural diagram of a thermometer with a large aspect ratio based on an elastic support ring provided by the present invention;

[0025] In the figure: 1-protection tube; 2-thermometer electrical interface; 3-thermometer installation interface; 4-armored cable; 5-elastic support ring; 6-thermometer probe. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0027] like Figure 1 As shown, the present invention provides a large aspect ratio thermometer based on an elastic support ring, comprising: a thermometer body, a protection tube 1, a thermometer electrical interface 2, a thermometer installation interface 3 and an elastic support ring 5; the thermometer body comprises an armored cable 4 and a thermometer probe 6.

[0028] A hole groove is opened at the center of the bottom of the inner cavity of the protection tube 1, and the diameter of the hole groove is the same as the diameter of the thermometer probe 6, and the depth of the hole groove is greater than the length of the thermometer probe 6. The thermometer probe 6 is arranged in the hole groove, and the free end of the thermometer probe 6 is in close contact with the bottom of the hole groove, and the other end of the thermometer probe 6 is fixedly connected to one end of the armored cable 4, and the other end of the armored cable 4 is fixedly connected to one end of the thermometer electrical interface 2, and the thermometer installation interface 3 is fixedly connected to the open end of the protection tube 1 through a thread; the elastic support ring 5 is sleeved on the armored cable 4.

[0029] The elastic support ring 5 includes an upper ring, a lower ring and a plurality of side strips, each of which has the same width and length, and is evenly spaced between the upper ring and the lower ring. The two ends of each side strip are fixedly connected to the upper ring and the lower ring, respectively, and the side strip is a bendable elastic structure. When the elastic support ring 5 is in a free state, the maximum spherical diameter of the elastic support ring 5 is greater than the diameter of the cavity of the thermometer protection tube 1. Specifically, the elastic support ring 5 can be an ellipsoidal lantern structure made of a metal material with high yield strength.

[0030] The upper collar of the elastic support ring 5 is fixedly connected to the armored cable 4 through mechanical extrusion of one end of the thermometer mounting interface 3; the lower collar of the elastic support ring 5 is not fixed, but is slidably connected to the armored cable 4 and can slide along the armored cable 4. The elastic support ring 5 can easily change its outer diameter when squeezed by external force, which can ensure that the elastic support ring 5 is in close contact with the inner wall of the protection tube 1. At the same time, the elastic change of the diameter of the elastic support ring 5 makes it very easy to disassemble and assemble the thermometer, and will not be affected by the deformation of the protection tube 1 or the diameter of the mounting interface 3.

[0031] When installing the thermometer body, the outer diameter of the elastic support ring 5 is changed by squeezing it, so that it can smoothly pass through the protection tube 1 and the thermometer installation interface 3, so that the thermometer body can be smoothly inserted into the protection tube 1. After the thermometer body is inserted into the protection tube 1, the edge strip of the elastic support ring 5 rebounds and always clings to the inner wall of the sleeve, so that the edge strip of the elastic support ring 5 supports the armored cable 4, ensuring that the armored cable 4 will not be deformed or drooped due to excessive length; the armored cable 4 is always in the axial position of the protection tube 1, thereby ensuring that the thermometer probe 6 is effectively in contact with the end of the protection tube 1, ensuring the measurement accuracy and response time of the thermometer. When there is pipeline vibration or fluid scouring that causes the thermometer protection tube 1 to vibrate, the elastic damping characteristics of the elastic support ring 5 can effectively alleviate the radial swing of the armored cable 4 in the protection tube 1, thereby preventing the thermometer probe 6 from detaching from the end of the protection tube 1 or generating a gap between the two, effectively reducing the impact of vibration on temperature measurement, and also greatly reducing the probability of failure of the core wire of the armored cable 4 inside the thermometer due to vibration.

[0032] In general, the protection tube 1 is welded to the wall of the container or pipe, and the interface form of the thermometer installation interface 3 is determined according to the interface of the protection tube 1. In general, the thermometer installation interface 3 is connected to the protection tube 1 through threads, and the thermometer body is fixed in the protection tube 1. The resistance value of the thermometer probe 6 is output to the processing unit of the temperature measurement circuit through the thermometer electrical interface 2 to complete the measurement of the temperature parameters of the process system.

[0033] When disassembling the thermometer body, the thermometer body can be directly pulled out. During the pulling out process, the elastic support ring 5 is naturally squeezed to change the outer diameter of the elastic support ring 5, and the protective tube 1 and the thermometer installation interface 3 can be freely passed through. The thermometer body can be directly pulled out of the protective tube 1 to complete the disassembly of the thermometer body.

[0034] The number of side strips of the elastic support ring 5 can be designed and adjusted according to the diameter of the armored cable. The larger the diameter, the more side strips can be designed to ensure effective support in all radial directions of the armored cable 4. The elastic support ring 5 is fixed to the armored cable 4 by mechanical extrusion of one end of the thermometer installation interface 3 to ensure that the thermometer body can be smoothly pulled out and disassembled from the protection tube 1.

[0035] The thermometer body and the protective tube 1 in the thermometer with a large aspect ratio based on an elastic support ring of the present invention need to be matched to ensure that the two have a high degree of matching. In some special applications, high temperature measurement accuracy and fast response time are required. In this case, the thermometer probe 6 and the armored cable 4 should be selected with a smaller diameter. At the same time, the diameter of the hole groove at the bottom of the protective tube 1 should match the diameter of the thermometer probe 6, and the assembly tolerance of the two should be minimized to ensure the temperature measurement accuracy and response time.

[0036] The present invention is described in detail above with reference to the accompanying drawings and embodiments, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of ordinary technicians in the field without departing from the purpose of the present invention. The contents not described in detail in the present invention can adopt the existing technology.

Claims

1. A thermometer with a large aspect ratio based on an elastic support ring, characterized in that: The thermometer comprises: a thermometer body, a protective tube (1), a thermometer electrical interface (2), a thermometer installation interface (3) and an elastic support ring (5); the thermometer body comprises an armored cable (4) and a thermometer probe (6); the thermometer probe (6) is arranged in the inner cavity of the protective tube (1); the free end of the thermometer probe (6) is in close contact with the bottom end of the inner cavity of the protective tube (1); the other end of the thermometer probe (6) is fixedly connected to one end of the armored cable (4); the other end of the armored cable (4) is fixedly connected to one end of the thermometer electrical interface (2); the thermometer installation interface (3) is fixedly connected to the open end of the protective tube (1); the elastic support ring (5) is sleeved on the armored cable (4); the elastic support ring (5) comprises an upper sleeve ring, a lower sleeve ring and a plurality of side strips; the plurality of side strips are arranged between the upper sleeve ring and the lower sleeve ring at equal intervals; the two ends of each side strip are respectively fixedly connected to the upper sleeve ring and the lower sleeve ring; the side strip is a bendable elastic structure; When the elastic support ring (5) is in a free state, the maximum spherical diameter of the elastic support ring (5) is greater than the diameter of the cavity of the thermometer protection tube (1); The upper sleeve ring of the elastic support ring (5) is fixedly connected to the armored cable (4), and the lower sleeve ring of the elastic support ring (5) is slidably connected to the armored cable (4).

2. A thermometer with a large aspect ratio based on an elastic support ring according to claim 1, characterized in that: The upper sleeve ring of the elastic support ring (5) is fixedly connected to the armored cable (4) through mechanical extrusion of the thermometer installation interface (3).

3. The thermometer with a large aspect ratio based on an elastic support ring according to claim 1, characterized in that: The elastic support ring (5) is an ellipsoidal lantern structure.

4. The thermometer with a large aspect ratio based on an elastic support ring according to claim 1, characterized in that: The elastic support ring (5) is made of a metal material with high yield strength.

5. The thermometer with a large aspect ratio based on an elastic support ring according to claim 1, characterized in that: A hole groove is provided at the center of the bottom end of the inner cavity of the protection tube (1), and a thermometer probe (6) is arranged in the hole groove, with the free end of the thermometer probe (6) in close contact with the bottom end of the hole groove.

6. A thermometer with a large aspect ratio based on an elastic support ring according to claim 5, characterized in that: The diameter of the hole groove is the same as the diameter of the thermometer probe (6), and the depth of the hole groove is greater than the length of the thermometer probe (6).

7. The thermometer with a large aspect ratio based on an elastic support ring according to claim 1, characterized in that: The thermometer installation interface (3) is fixedly connected to the cavity of the protection tube (1) via threads.

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