Pre-debugging method for thermal resistor installed in hidden mode

Abstract

The invention relates to a pre-debugging method for thermal resistors installed in a hidden mode. The pre-debugging method comprises the following steps that S1, classified statistics is conducted on the thermal resistors installed in the hidden mode; s2, off-line detection before the thermal resistor is installed; s3, checking the installation condition of a thermal resistor and a connecting line; and S4, online monitoring in the hiding process after the thermal resistor is installed. According to the method, the specific content, requirements and method of inspection in the pre-debugging process of the thermal resistor which is installed in a hidden mode are defined, implementation is convenient, and construction quality is convenient to control; off-line detection is carried out on each thermal resistor before each thermal resistor is connected into an instrument loop, so that the thermal resistor of which the measurement error does not meet the process requirement is prevented from being put into use, the defects in the aspects of manufacturing and mounting of the thermal resistor can be found in advance, and the thermal resistor can be replaced in time; and meanwhile, through online monitoring, unnecessary reworking caused by the fact that the damaged thermal resistor and a connecting line thereof are difficult to find in time in the process of erecting, dismantling and hiding the scaffold of the thermal resistor is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of installation and debugging of instrument systems, in particular to a pre-debugging method for a concealed thermal resistor. Background Art

[0002] In industrial production temperature detection, thermal resistors are the most commonly used temperature detection elements in the medium and low temperature zones. They have the characteristics of high measurement accuracy and stable performance. Generally, thermal resistors are easy to replace and maintain. However, for thermal resistors that are hidden after installation, especially those deeply buried by insulation materials or covered by other materials, replacement and maintenance are very inconvenient and the cost is extremely high. Whether the hidden thermal resistors can be used normally is not only directly related to the accuracy, reliability and stability of the measurement, but also will affect the construction progress of the project and the quality of the final product.

[0003] During the construction phase, the common method used is to refer to the pre-installation inspection method of ordinary thermal resistors, and only conduct a simple inspection of the thermal resistor's on / off and connection lines at room temperature. There is no unified inspection and pre-commissioning method at the construction site. When installing pipelines and equipment where thermal resistors are located, scaffolding may be required for high-altitude operations. During the erection, removal and concealment of the scaffolding, the thermal resistor or its connection lines may be damaged.

[0004] Traditional methods have the following disadvantages for thermal resistors that are concealed after installation: (1) It is difficult to promptly detect thermal resistors with unqualified manufacturing and installation quality, especially those with unqualified response time; (2) If problems are found after the thermal resistor is installed and put into use, adjustments or rework are required, which will affect the construction period and be extremely costly; (3) The construction quality is greatly affected by human factors such as the skill level and sense of responsibility of the personnel. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a pre-debugging method for a thermal resistor that is deeply buried or concealed in other ways after installation and is inconvenient to maintain and replace, so as to ensure the normal use of the concealed thermal resistor and avoid problems such as inaccurate detection and unusable due to quality problems of the thermal resistor itself, improper installation, etc.; while improving construction efficiency, the reliability and accuracy of the thermal resistor detection element in operation are ensured.

[0006] The technical solution adopted by the present invention to solve the technical problem is: to provide a pre-debugging method for a concealed thermal resistor, the pre-debugging method comprising the following steps:

[0007] S1. Classify and count the concealed thermal resistors:

[0008] According to the instrument control schematic diagram, classify the concealed thermal resistors according to their installation locations and workstation numbers, and make a classification statistical diagram;

[0009] S2. Offline detection of thermal resistor before installation:

[0010] S2.1. Insulation inspection: confirm that the insulation of the external protection tube and the ground of each thermal resistor lead wire is qualified. For double-branch thermal resistors, confirm that the insulation between the two thermal resistor leads is also qualified.

[0011] S2.2. Measure the resistance value of the thermal resistor at room temperature. Compare it with the thermal resistor graduation table of this model. The measured resistance value should be consistent with the corresponding standard resistance value in the graduation table at the test temperature. Confirm that the resistance value is correct.

[0012] S2.3, simulate the use conditions and measure the resistance value and response time of each thermal resistor;

[0013] S2.4. For thermal resistors that meet the requirements in S2.1, S2.2 and S2.3, make qualified marks in the remarks column of the statistical diagram of concealed thermal resistor classification;

[0014] S3. Check the installation of thermal resistors and connecting lines:

[0015] S3.1. Insulation inspection of connecting cable lines:

[0016] Check the insulation of the cable connected to the thermal resistor lead wire. The insulation resistance between the core wires, the core wire to the shield, the core wire to the sheath and the ground meet the requirements.

[0017] S3.2, thermal resistance and circuit installation inspection:

[0018] Confirm the installation position and workstation number of the installed thermal resistor, the fitting condition of the surface mounted thermal resistor, the thermal resistor protection tube, the insertion depth of the thermal resistor, the cable laying condition, the distance between the cable and the equipment, and the fixing condition of the thermal resistor to ensure that the thermal resistor itself is installed correctly and the line laying meets the use requirements;

[0019] S3.3 Connector inspection:

[0020] Check the line joints connected to the thermal resistor lead wires by welding to ensure that the cables are connected correctly, the welding is firm, and the insulation of the welding parts is well restored;

[0021] Check the line connectors connected to the thermal resistor lead wires through terminal transition to ensure that the cables are connected correctly and the terminals are firmly connected;

[0022] S4. Online monitoring of the thermal resistor during the concealed process after installation.

[0023] As a supplement to the technical solution described in the present invention, in the S2.3, the specific steps are as follows: for thermistors used for low-temperature and ultra-low-temperature working condition detection, liquid nitrogen is used as the test medium, the resistance value and response time of each thermistor are measured, the thermistors that do not meet the use requirements are excluded, and the thermistors that meet the requirements are marked according to the installation position and work station number of the schematic diagram; for thermistors used for medium-temperature working condition detection, boiling water is used as the test medium, the resistance value and response time of each thermistor are measured, the thermistors that do not meet the use requirements are excluded, and the thermistors that meet the requirements are marked according to the installation position and work station number of the schematic diagram.

[0024] As a supplement to the technical solution described in the present invention, in the above S2.1, the insulation check uses a megohmmeter with a voltage level of 100V to check the insulation of each thermal resistor lead wire to the external protection tube and the ground to confirm that the thermal resistor insulation is qualified.

[0025] As a supplement to the technical solution described in the present invention, in the S3.1, a megohmmeter with a voltage level of 250V is used for inspection.

[0026] As a supplement to the technical solution described in the present invention, in the S4, the specific steps are as follows: during the filling of insulation materials or other materials, the temperatures of all concealed thermal resistors are monitored online. For the concealment of double-branch thermal resistors, the outputs of the two groups of thermal resistors need to be monitored simultaneously. If there is an abnormality, the filling is stopped and processed. After the processing is completed, the filling is continued to ensure that the thermal resistors and connecting cables are not damaged during the concealment process.

[0027] Beneficial effects: The present invention relates to a pre-debugging method for concealed thermal resistors, which clarifies the specific content, requirements and methods of inspection during the pre-debugging of concealed thermal resistors, is convenient for implementation, and is easy to control the construction quality; since each thermal resistor is tested offline before being connected to the instrument loop, it is avoided that thermal resistors whose measurement errors do not meet the process requirements are put into use, and defects in the manufacture and installation of thermal resistors can be discovered in advance and replaced in time; at the same time, through online monitoring, it is avoided that during the erection, dismantling and concealment of scaffolding of the thermal resistors, damaged thermal resistors and their connecting lines are difficult to be discovered in time, resulting in unnecessary rework. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the structure of the present invention;

[0029] Figure 2 It is a schematic diagram of the present invention for measuring a thermal resistor under simulated use conditions;

[0030] Figure 3 It is a schematic diagram of the classification statistical schematic table described in the present invention.

[0031] 1. Test container, 2. Test medium, 3. Test line, 4. Thermal resistor to be tested, 5. Test instrument. DETAILED DESCRIPTION

[0032] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0033] An embodiment of the present invention relates to a pre-commissioning method for a concealed thermal resistor, such as Figure 1-3 As shown, the pre-debugging method includes the following steps:

[0034] S1. Classify and count the concealed thermal resistors:

[0035] According to the instrument control schematic diagram, classify the concealed thermal resistors according to their installation locations and workstation numbers, and make a classification statistical diagram;

[0036] S2. Offline detection of thermal resistor before installation:

[0037] S2.1. Insulation inspection: confirm that the insulation of the external protection tube and the ground of each thermal resistor lead wire is qualified. For double-branch thermal resistors, confirm that the insulation between the two thermal resistor leads is also qualified.

[0038] S2.2. Measure the resistance value of the thermal resistor at room temperature. Compare it with the thermal resistor graduation table of this model. The measured resistance value should be consistent with the corresponding standard resistance value in the graduation table at the test temperature. Confirm that the resistance value is correct.

[0039] S2.3. Simulate the use conditions and measure the resistance value and response time of each thermal resistor. For thermal resistors used for low-temperature and ultra-low-temperature conditions, use liquid nitrogen as the test medium, measure the resistance value and response time of each thermal resistor, exclude the thermal resistors that do not meet the use requirements, and mark the thermal resistors that meet the requirements according to the installation position and work position number of the schematic diagram. For thermal resistors used for medium-temperature conditions, use boiling water as the test medium, measure the resistance value and response time of each thermal resistor, exclude the thermal resistors that do not meet the use requirements, and mark the thermal resistors that meet the requirements according to the installation position and work position number of the schematic diagram.

[0040] Please refer to the schematic diagram of measuring the thermal resistor under simulated working conditions Figure 2As shown, the test container 1 contains a test medium 2, which is liquid nitrogen or boiling water. A thermal resistor 4 is placed in the test medium 2, and the upper end of the thermal resistor 4 is connected to a test instrument 5 through a test line 3.

[0041] S2.4. For thermal resistors that meet the requirements in S2.1, S2.2 and S2.3, make qualified marks in the remarks column of the statistical diagram of concealed thermal resistor classification;

[0042] S3. Check the installation of thermal resistors and connecting lines:

[0043] S3.1. Insulation inspection of connecting cable lines:

[0044] Use a 250V megohmmeter to check the insulation of the cable connected to the thermal resistor lead wire. The insulation resistance between the core wires, the core wire to the shield, the core wire to the outer sheath and the ground meet the requirements.

[0045] S3.2, thermal resistance and circuit installation inspection:

[0046] Confirm the installation position and workstation number of the installed thermal resistor, the fitting condition of the surface mounted thermal resistor, the thermal resistor protection tube, the insertion depth of the thermal resistor, the cable laying condition, the distance between the cable and the equipment, and the fixing condition of the thermal resistor to ensure that the thermal resistor itself is installed correctly and the line laying meets the use requirements;

[0047] S3.3 Connector inspection:

[0048] Check the line joints connected to the thermal resistor lead wires by welding to ensure that the cables are connected correctly, the welding is firm, and the insulation of the welding parts is well restored;

[0049] Check the line connectors connected to the thermal resistor lead wires through terminal transition to ensure that the cables are connected correctly and the terminals are firmly connected;

[0050] S4. Online monitoring of the concealed process of the thermal resistor after installation; online monitoring of the temperature of all concealed thermal resistors during the filling of insulation materials or other materials. For the concealed process of double-branch thermal resistors, the outputs of the two groups of thermal resistors must be monitored simultaneously. If there is any abnormality, stop filling and handle it. Continue filling after the processing is completed to ensure that the thermal resistors and connecting cables are not damaged during the concealment process.

[0051] In the above-mentioned S2.1, the insulation check uses a 100V voltage level megohmmeter to check the insulation of each thermal resistor lead wire to the external protection tube and the ground to confirm that the thermal resistor insulation is qualified.

[0052] Concealment in the present invention means that the thermal resistor (including the junction box) and part of the measurement circuit connected thereto are filled with other materials or blocked by obstacles after the construction is completed, resulting in that the thermal resistor (including the junction box) and part of the measurement circuit connected thereto cannot be normally touched, maintained or replaced. The double-branch thermal resistor in the present invention refers to a group of thermal resistors consisting of two thermal resistors, which are installed in an outer protective tube, measure the temperature of the same point, and have two groups of outputs.

[0053] The present invention clarifies the specific content, requirements and methods of inspection during the pre-debugging of concealed thermal resistors, which is convenient for implementation and for controlling the construction quality. Since each thermal resistor is tested offline before being connected to an instrument loop, it is avoided that a thermal resistor whose measurement error does not meet the process requirements is put into use, and defects in the manufacture and installation of the thermal resistor can be discovered in advance and replaced in time. At the same time, through online monitoring, it is avoided that the damaged thermal resistor and its connecting line are difficult to be discovered in time during the process of scaffold erection, dismantling and concealment of the thermal resistor, which causes unnecessary rework.

[0054] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0055] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" may include both "above" and "below". The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0056] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0057] The above is a detailed introduction to a pre-debugging method for a concealed thermal resistor provided by the present application. Specific examples are used in this article to illustrate the principle and implementation method of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for a person skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A pre-debugging method for a concealed thermal resistor, characterized in that: The pre-debugging method comprises the following steps: S1. Classify and count the concealed thermal resistors: According to the instrument control schematic diagram, classify the concealed thermal resistors according to their installation locations and workstation numbers, and make a classification statistical diagram; S2. Offline detection of thermal resistor before installation: S2.

1. Insulation inspection: confirm that the insulation of the external protection tube and the ground of each thermal resistor lead wire is qualified. For double-branch thermal resistors, confirm that the insulation between the two thermal resistor leads is also qualified. S2.

2. Measure the resistance value of the thermal resistor at room temperature. Compare it with the thermal resistor graduation table of this model. The measured resistance value should be consistent with the corresponding standard resistance value in the graduation table at the test temperature. Confirm that the resistance value is correct. S2.3, simulate the use conditions and measure the resistance value and response time of each thermal resistor; S2.

4. For thermal resistors that meet the requirements in S2.1, S2.2 and S2.3, make qualified marks in the remarks column of the statistical diagram of concealed thermal resistor classification; S3. Check the installation of thermal resistors and connecting lines: S3.

1. Insulation inspection of connecting cable lines: Check the insulation of the cable connected to the thermal resistor lead wire. The insulation resistance between the core wires, the core wire to the shield, the core wire to the sheath and the ground meet the requirements. S3.2, thermal resistance and circuit installation inspection: Confirm the installation position and workstation number of the installed thermal resistor, the fitting condition of the surface mounted thermal resistor, the thermal resistor protection tube, the insertion depth of the thermal resistor, the cable laying condition, the distance between the cable and the equipment, and the fixing condition of the thermal resistor to ensure that the thermal resistor itself is installed correctly and the line laying meets the use requirements; S3.3 Connector inspection: Check the line joints connected to the thermal resistor lead wires by welding to ensure that the cables are connected correctly, the welding is firm, and the insulation of the welding parts is well restored; Check the line connectors connected to the thermal resistor lead wires through terminal transition to ensure that the cables are connected correctly and the terminals are firmly connected; S4. Online monitoring of the thermal resistor during the concealed process after installation.

2. A method for pre-debugging a concealed thermal resistor according to claim 1, characterized in that: In the above S2.3, the specific steps are as follows: for thermistors used for low-temperature and ultra-low-temperature working condition detection, liquid nitrogen is used as the test medium, the resistance value and response time of each thermistor are measured, the thermistors that do not meet the use requirements are excluded, and the thermistors that meet the requirements are marked according to the installation position and work station number of the schematic diagram; for thermistors used for medium-temperature working condition detection, boiling water is used as the test medium, the resistance value and response time of each thermistor are measured, the thermistors that do not meet the use requirements are excluded, and the thermistors that meet the requirements are marked according to the installation position and work station number of the schematic diagram.

3. The pre-debugging method of a concealed thermal resistor according to claim 1, characterized in that: In the above-mentioned S2.1, the insulation check uses a 100V voltage level megohmmeter to check the insulation of each thermal resistor lead wire to the external protection tube and the ground to confirm that the thermal resistor insulation is qualified.

4. A method for pre-debugging a concealed thermal resistor according to claim 1, characterized in that: In the above-mentioned S3.1, a megohmmeter with a voltage level of 250V is used for inspection.

5. The pre-debugging method of a concealed thermal resistor according to claim 1, characterized in that: In the above-mentioned S4, the specific steps are as follows: during the process of filling the insulation material or other materials, the temperatures of all concealed thermistors are monitored online. During the concealment process of the double-branch thermistors, the outputs of the two groups of thermistors need to be monitored simultaneously. If there is any abnormality, the filling is stopped and processed. After the processing is completed, the filling is continued to ensure that the thermistors and the connecting cables are not damaged during the concealment process.

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