Cable joint lead sealing detection device and detection method thereof

Abstract

The invention discloses a cable joint lead sealing detection device, which comprises a heat insulation belt, at least one thermocouple, a temperature transmitter, a single-chip microcomputer and an upper computer, and is characterized in that the thermocouple is fixed on the lead sealing surface of a cable joint to be detected through the heat insulation belt, the thermocouple is connected with the single-chip microcomputer through the temperature transmitter, and the single-chip microcomputer is connected with the upper computer through the temperature transmitter. The single-chip microcomputer is connected with the upper computer. A measuring scale is arranged on the outer side face of the heat insulation belt. Meanwhile, the invention discloses a detection method based on the cable joint lead sealing detection device. The device is simple in structure, convenient to operate, accurate and rapid in detection and capable of providing reliable support for cable detection work.

Description

Technical Field

[0001] The invention relates to cable detection technology, and in particular to a cable joint lead sealing detection device and a detection method thereof. Background Art

[0002] Cable joints are an important part of the power transmission system, which can ensure the safe and reliable electrical connection between cables. The lead seal of the cable joint, as an important auxiliary component of the cable joint, not only has the functions of sealing, waterproofing, and dustproofing, but also protects the cable joint from external environmental interference and prolongs the service life of the cable. The quality of the lead seal directly affects the long-term stability and safety of the cable joint. Therefore, ensuring the quality of the lead seal is crucial to the safe operation of the power system.

[0003] However, there are major problems with the current production and processing standards for cable joint seals. So far, there has been no unified national standard (GB) issued in China to specify the design, materials, processing technology and quality requirements for cable joint seals. This has led to different manufacturers producing seals based on different standards and technical requirements, resulting in uneven quality of seals. Some products may even have problems such as poor sealing and poor anti-aging performance, which affects the long-term operating reliability of cable joints.

[0004] What is more serious is that there is a lack of effective lead seal quality detection equipment on the market, which makes it impossible to effectively evaluate and inspect the quality of lead seals during production or use. The quality of lead seals often relies on manual inspection or visual inspection, which is highly subjective and inaccurate and cannot meet the requirements of modern power equipment for high precision and high reliability. At the same time, whether the lead seal is qualified is closely related to the environment in which it is located (such as temperature and humidity), so the existing detection methods are difficult to comprehensively and objectively evaluate the quality of the lead seal. Summary of the invention

[0005] The first purpose of the present invention is to overcome the deficiencies of the above prior art and provide a cable joint lead sealing detection device. The cable joint lead sealing detection device has a simple structure and is easy to operate, and can meet the detection requirements of different load currents, different lead sealing positions, and different lead sealing thicknesses.

[0006] The second object of the present invention is to provide a detection method for a cable joint lead sealing detection device.

[0007] The first purpose of the present invention is achieved through the following technical scheme: the cable joint lead sealing detection device comprises an insulation belt, at least one thermocouple, a temperature transmitter, a single-chip microcomputer and a host computer, wherein the thermocouple is fixed to the lead sealing surface of the cable joint to be detected through the insulation belt, the thermocouple is connected to the single-chip microcomputer through the temperature transmitter, and the single-chip microcomputer is connected to the host computer; a measuring scale is provided on the outer side of the insulation belt.

[0008] Preferably, the number of the thermocouples is at least 2, and all the thermocouples are evenly distributed around the circumference of the axis of the lead seal.

[0009] Preferably, the thermal insulation belt is provided with Velcro.

[0010] Preferably, a display and a storage card are provided inside the single chip microcomputer.

[0011] The detection method of the cable joint lead sealing detection device based on the first purpose comprises the following steps:

[0012] S1. Put all the thermocouples close to the circumferential surface of the lead seal, and then wrap the thermocouples and the lead seal with an insulating tape. By observing the measuring scale of the insulating tape, the circumference of the lead seal is obtained, and the thickness of the lead seal is calculated using the circumference;

[0013] S2. Measure the current and power-on time of the cable at the lead sealing position through the host computer settings;

[0014] S3. The thermocouple detects the temperature at the sealing edge in real time, and determines the temperature when power is turned on and after power is turned off. The temperature before and after power is then subtracted to obtain a temperature variable Δ. This temperature variable is compared with the data in the standard database stored in the storage card, and the comparison result is used to determine whether the sealing lead meets the standard.

[0015] Preferably, in step S2, the power-on time is at least 1 hour.

[0016] Preferably, in step S2, the current is 400A to 800A.

[0017] Preferably, in step S3, the thermocouple detects the temperature at the sealing edge in real time once every 10 seconds, and transmits the detection structure to the single chip microcomputer through the temperature transmitter.

[0018] Preferably, in step S3, the temperature at the beginning of power-on and after power-off is determined by the average of all thermocouple detection values.

[0019] The present invention has the following advantages over the prior art:

[0020] 1. The cable joint lead seal detection device of the present invention is mainly composed of an insulation belt, at least one thermocouple, a temperature transmitter, a single chip microcomputer and a host computer. It can monitor the temperature change at the lead seal in real time to determine whether the lead seal has good sealing performance and environmental resistance. At the same time, the present invention can also determine whether the cable has defects and the type of defects through the temperature difference before and after power-off.

[0021] 2. The present invention can not only fill the gap of the lack of standardized testing tools in the market, but also help promote the quality standardization of the cable joint industry, improve the operational reliability of power equipment, and reduce the risk of equipment failure caused by substandard lead sealing quality. At the same time, the promotion and application of the present invention can provide relevant enterprises with a scientific and accurate lead sealing quality testing method to ensure the long-term stable operation of cable joints. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the first viewing angle of the cable joint lead sealing detection device of the present invention.

[0023] Figure 2 It is a schematic diagram of the cable joint lead sealing detection device of the present invention from a second viewing angle.

[0024] Figure 3 It is a schematic diagram from a first viewing angle of the cable joint lead sealing detection device of the present invention connected to a cable to be detected.

[0025] Figure 4 It is a schematic diagram from a second viewing angle of the cable joint lead sealing detection device of the present invention connected to a cable to be detected.

[0026] Figure 5 It is a schematic diagram of a single-site machine, a display and a storage card of the present invention.

[0027] Among them, 1 is an insulating belt, 2 is a thermocouple, 3 is a temperature transmitter, 4 is a single-chip microcomputer, 5 is a host computer, 6 is a measuring ruler, 7 is a Velcro, 8 is a display, 9 is a storage card, 10 is a cable, and 11 is a sealing lead. DETAILED DESCRIPTION

[0028] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0029] like Figure 1 and Figure 2 The cable joint lead seal detection device shown includes an insulation belt, at least one thermocouple, a temperature transmitter, a single-chip microcomputer and a host computer. The thermocouple is fixed to the lead seal surface of the cable joint to be detected through the insulation belt, the thermocouple is connected to the single-chip microcomputer through the temperature transmitter, and the single-chip microcomputer is connected to the host computer; the outer side of the insulation belt is provided with a measuring scale. The number of the thermocouples is at least 2, and all the thermocouples are evenly distributed around the axis of the lead seal. Specifically, as Figure 3 and Figure 4As shown, the number of thermocouples in this embodiment is 2, and these 2 thermocouples are symmetrically arranged relative to the axis of the lead seal, and then fixed to the circumferential surface of the lead seal by winding the insulation belt, so that the temperature of the lead seal can be detected in real time. The number of thermocouples is not limited to 2, and can be determined according to the size of the cable to ensure the accuracy of the detection. At the same time, the insulation belt not only plays the role of being fixed to the thermocouple, but also prevents the thermocouple from being affected by the outside world to improve the accuracy of the thermocouple temperature detection. Moreover, the thermocouple is fixed with the insulation belt, which is convenient to operate and can meet the requirements of the cross-sectional area size, lead sealing position, load current size, etc. of the lead seal of different cable joints, and has wide applicability. The measuring scale is set on the outer side of the insulation belt, which is convenient for the detection personnel to directly observe the data with high accuracy.

[0030] The insulation belt is provided with Velcro. Specifically, the fur surface of the Velcro is arranged on the inner side of the insulation belt, and the back of the Velcro is arranged on the outer end of the insulation belt. This structure is simple, convenient for fixing the insulation belt, and can meet the detection of cables of different sizes.

[0031] like Figure 5 As shown, the single chip microcomputer is provided with a display and a storage card. Specifically, the storage card stores the different temperature differences caused by different currents and different defect types at the lead sealing of the cable joint, and can also store the data obtained by the thermocouple detection, that is, the data detected by the thermocouple in real time is transmitted to the single chip microcomputer through the temperature transmitter, and then stored in the storage card. The display displays the data detected by the thermocouple in real time, and also displays the result of the data processing by the single chip microcomputer.

[0032] The detection method of the cable joint lead sealing detection device based on the first purpose comprises the following steps:

[0033] S1. Place all thermocouples tightly against the circumferential surface of the lead seal, and then wrap the thermocouples and the lead seal with an insulating tape. By observing the measuring scale of the insulating tape, the circumference of the lead seal is obtained, and the thickness of the lead seal is calculated using the circumference. Specifically, the circumference of the lead seal is obtained as L, and the circumference formula L=πd is used to obtain the diameter d of the lead seal. According to the cable specifications, the diameter of the cable can be determined as d', and the thickness of the lead seal can be determined as (d-d') / 2.

[0034] S2. The upper computer is used to set the current size and power-on time of the cable at the lead seal. The current size in this embodiment is 600A, and the power-on time is 1 hour. At the same time, the time interval between each transmission of the temperature data detected by the thermocouple by the temperature transmitter is set, and the temperature collection time is set every 10 seconds to facilitate the understanding of the temperature changes at the lead seal.

[0035] S3. The thermocouple detects the temperature at the sealing edge in real time, and determines the temperature when power is turned on and after power is turned off. The temperature before and after power is then subtracted to obtain a temperature variable Δ. This temperature variable is compared with the data in the standard database stored in the storage card, and the comparison result is used to determine whether the sealing lead meets the standard.

[0036] Specifically, the quality of the lead seal is closely related to the thermal conductivity of its material. A lead seal with good quality will show a stable temperature change curve after being heated, while a low-quality lead seal may cause abnormal temperature changes due to poor sealing or unqualified materials. This paper can effectively reflect the sealing and overall quality of the lead seal through the change in temperature at the lead seal.

[0037] In step S3, the temperature at the beginning of power on and after power off is determined by the average of all thermocouple detection values. In this embodiment, two thermocouples are used, and the temperature values ​​of the first thermocouple when detecting are T 11 、T 12 、T 13 …T 1n The temperature values ​​of the second thermoelectric test are T 21 、T 22 、T 23 …T 2n , where n is a natural number. That is, T 11 and T 21 are the temperatures detected by the first thermocouple and the second thermocouple when the cable is first powered on, then T 1n and T 2n The first thermocouple and the second thermocouple respectively detect the last temperature value after the cable is powered off. It can be seen that the temperature at the beginning of power on and after power off is T1 = (T 11 +T 21 ) / 2 and T n =(T 1n and T 2n ) / 2, and then make a difference to get the temperature variable:

[0038] Δ=T n -T1;

[0039] After the single chip microcomputer performs the above data processing, it calls up the temperature difference stored in the storage card and compares it with the above obtained temperature variable to determine whether the lead seal has defects and the type of defects, and transmits the comparison result to the display and to the host computer for storage.

[0040] The above specific implementation modes are preferred embodiments of the present invention and cannot be used to limit the present invention. Any other changes or other equivalent replacement methods that do not deviate from the technical solution of the present invention are included in the protection scope of the present invention.

Claims

1. Cable joint lead sealing detection device, characterized by: It includes an insulation belt, at least one thermocouple, a temperature transmitter, a single-chip microcomputer and a host computer. The thermocouple is fixed to the lead sealing surface of the cable joint to be tested through the insulation belt, the thermocouple is connected to the single-chip microcomputer through the temperature transmitter, and the single-chip microcomputer is connected to the host computer; a measuring scale is provided on the outer side of the insulation belt.

2. The cable joint lead sealing detection device according to claim 1 is characterized in that: The number of the thermocouples is at least 2, and all the thermocouples are evenly distributed around the circumference of the axis of the lead seal.

3. The cable joint lead sealing detection device according to claim 1, characterized in that: The heat insulating belt is provided with Velcro.

4. The cable joint lead sealing detection device according to claim 1, characterized in that: A display and a storage card are arranged inside the single chip computer.

5. A detection method based on the cable joint lead sealing detection device according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Put all the thermocouples close to the circumferential surface of the lead seal, and then wrap the thermocouples and the lead seal with an insulating tape. By observing the measuring scale of the insulating tape, the circumference of the lead seal is obtained, and the thickness of the lead seal is calculated using the circumference; S2. Measure the current and power-on time of the cable at the lead sealing position through the host computer settings; S3. The thermocouple detects the temperature at the sealing edge in real time, and determines the temperature when power is turned on and after power is turned off. The temperature before and after power is then subtracted to obtain a temperature variable Δ. This temperature variable is compared with the data in the standard database stored in the storage card, and the comparison result is used to determine whether the sealing lead meets the standard.

6. The detection method of the cable joint lead sealing detection device according to claim 5, characterized in that: In step S2, the power-on time is at least 1 hour.

7. The detection method of the cable joint lead sealing detection device according to claim 5, characterized in that: In step S2, the current is 400A to 800A.

8. The detection method of the cable joint lead sealing detection device according to claim 5, characterized in that: In step S3, the thermocouple detects the temperature at the sealing edge in real time once every 10 seconds, and transmits the detection structure to the single chip microcomputer through the temperature transmitter.

9. The detection method of the cable joint lead sealing detection device according to claim 5, characterized in that: In step S3, the temperature at the beginning of power-on and after power-off is determined by the average of all the thermocouple detection values.

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