CN110986852A - Cable detection method - Google Patents
Cable detection method Download PDFInfo
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- CN110986852A CN110986852A CN201911232362.2A CN201911232362A CN110986852A CN 110986852 A CN110986852 A CN 110986852A CN 201911232362 A CN201911232362 A CN 201911232362A CN 110986852 A CN110986852 A CN 110986852A
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- cable
- measuring
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- test piece
- insulation
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B21/00—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant
- G01B21/02—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant for measuring length, width, or thickness
- G01B21/08—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant for measuring length, width, or thickness for measuring thickness
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
- G01B11/2408—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures for measuring roundness
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B5/00—Measuring arrangements characterised by the use of mechanical techniques
- G01B5/08—Measuring arrangements characterised by the use of mechanical techniques for measuring diameters
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B5/00—Measuring arrangements characterised by the use of mechanical techniques
- G01B5/20—Measuring arrangements characterised by the use of mechanical techniques for measuring contours or curvatures
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/08—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/025—Measuring very high resistances, e.g. isolation resistances, i.e. megohm-meters
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
- G01R31/1227—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials
- G01R31/1263—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials of solid or fluid materials, e.g. insulation films, bulk material; of semiconductors or LV electronic components or parts; of cable, line or wire insulation
- G01R31/1272—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials of solid or fluid materials, e.g. insulation films, bulk material; of semiconductors or LV electronic components or parts; of cable, line or wire insulation of cable, line or wire insulation, e.g. using partial discharge measurements
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
The invention discloses a cable detection method, which comprises the following steps: step 1, measuring the size of a cable; step 2, testing the mechanical property of the cable; and 3, testing the electrical performance of the cable. The cable detection method is simple and easy to master, clear in result and easy to distinguish, can comprehensively detect the quality of the cable, and improves the use safety of the cable.
Description
Technical Field
The invention relates to the technical field of cable production detection, in particular to a cable detection method.
Background
In recent years, Chinese economy develops rapidly, and the expanding development of the wire and cable industry is promoted to a great extent, so that a large amount of market demands cause fake and shoddy products to be popular, and a plurality of personal and property safety accidents are caused. In order to improve the product quality of the electric wire and the cable, ensure the safe operation of a power system and accelerate the stable development of national economy, a comprehensive detection project and a scientific detection method are necessary.
Therefore, it is urgently needed to provide a cable detection method for carefully and carefully performing quality inspection on the produced cable, and the cable can be normally used after being confirmed to be in accordance with the specification.
Disclosure of Invention
The invention aims to provide a cable detection method which is simple and easy to master in operation, clear in result and easy to distinguish, can comprehensively detect the quality of a cable and improves the use safety of the cable.
In order to achieve the above object, the present invention provides a cable detection method, including:
step 1, measuring the size of a cable;
step 2, testing the mechanical property of the cable;
and 3, testing the electrical performance of the cable.
Preferably, step 1 comprises:
step 1.1, measuring the insulation thickness;
step 1.2, measuring the thickness of the sheath;
and 1.3, measuring the ovality of the external dimension seam allowance.
Preferably, step 1.1 comprises preparing the sample, removing all the sheath from the insulation, extracting the conductor and the isolation layer; if the inner and outer semiconductor layers are adhered together with the insulation, the inner and outer semiconductor layers do not need to be removed; each test piece consisted of an insulating sheet cut along a plane perpendicular to the axis of the conductor using a sharp blade. The cores of the unsheathed flat cord should not be separated, and if the insulation has embossed marking indentations, the test piece should take a section containing the markings.
Preferably, said step 1.2 comprises: firstly, removing all elements inside and outside the sheath, and cutting a thin sheet by a blade along a plane vertical to the axis of the cable; if the jacket is provided with the impression mark dent, the test piece should take a section containing the mark; secondly, when the inner side of the test piece is circular, 6 points are measured in the standard radial direction; if the inner circular surface of the test piece is irregular or not smooth in nature, 6 points are measured radially at the thinnest part of the sheath according to the standard; when a conductor is arranged on the inner side of the test piece to form a deep groove, the radial measurement is carried out on the bottom of each groove according to the standard; for the sheathed flat cord, it should be measured in the direction parallel to the minor axis and the major axis of the cross section of each insulated wire core, respectively, as a standard, and it is necessary to measure a point at the thinnest point; the six-core and the following sheathed flat cables are required to be as follows: measuring at both ends of the arc along the long axis of the cross section, and measuring at the first and last insulated wire cores at both flat sides; if the thinnest thickness is not among the several measurements, the thickness measurement in the direction of the thinnest point and the opposite direction should be increased; and finally, averaging the numerical values obtained in the previous step and accurately obtaining the numerical values 2 bits after the decimal point.
Preferably, said step 1.3 comprises: when the outer diameter of the cable is not more than 25mm, respectively measuring in two mutually perpendicular directions by using a micrometer or a projector; when the outer diameter of the cable exceeds 25mm, measuring the circumference of the cable by using a measuring belt, and then calculating the diameter; the flat cable is measured along the major and minor axes of the cross-section with a micrometer or projector.
Preferably, the step 2 includes: cutting the wire core sample into small sections of 100mm, drawing out the conductor, removing all the outer protective layers, marking each tubular sample, and before an aging experiment, storing all the samples at the temperature of 18-28 ℃ for 3h while avoiding direct sunlight; aging the test piece by using a natural ventilation oven and a pressure ventilation oven, wherein air flows through the surface of the test piece in the treatment process and is discharged from the top of the oven, and the replacement frequency of all air in the oven is not less than 8 times and not more than 20 times per hour at the specified aging temperature; before the tensile test, all the test pieces are stored for 3h at the temperature of 18-28 ℃, then the tensile test is carried out on the test pieces by using a tensile tester, wherein the moving speed of a chuck of the tensile tester is 200-300mm/min, and the maximum tensile force is measured and recorded during the test.
Preferably, the step 3 comprises: conductor resistance inspection, product cable voltage test, insulation wire core voltage test and insulation resistance detection.
According to the technical scheme, the size of the cable is measured to ensure that the appearance size of the cable meets the use requirement; secondly, testing the mechanical property of the cable to ensure that the service life of the cable meets the requirement in the long-term use process; and finally, carrying out electrical performance test on the cable to ensure that the performance of the cable can meet the requirements on the electrical performance and can sufficiently bear load.
Additional features and advantages of the invention will be set forth in the detailed description which follows.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:
fig. 1 is a schematic flow chart of a cable detection method provided by the present invention.
Detailed Description
The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.
In the present invention, unless otherwise specified, the directional words "upper, lower, top, bottom" and the like included in a term merely represent the orientation of the term in a conventional use state or a colloquial meaning understood by those skilled in the art, and should not be construed as limiting the term.
Referring to fig. 1, the present invention provides a cable detection method, including:
step 1, measuring the size of a cable;
step 2, testing the mechanical property of the cable;
and 3, testing the electrical performance of the cable.
According to the technical scheme, the size of the cable is measured to ensure that the appearance size of the cable meets the use requirement; secondly, testing the mechanical property of the cable to ensure that the service life of the cable meets the requirement in the long-term use process; and finally, carrying out electrical performance test on the cable to ensure that the performance of the cable can meet the requirements on the electrical performance and can sufficiently bear load.
In order to perform measurement and detection on the cable size in all aspects, step 1 preferably includes:
step 1.1, measuring the insulation thickness;
step 1.2, measuring the thickness of the sheath;
and 1.3, measuring the ovality of the external dimension seam allowance.
Further, step 1.1 includes preparing a sample, removing all the protective layers from the insulation, and extracting the conductor and the isolation layer; if the inner and outer semiconductor layers are adhered together with the insulation, the inner and outer semiconductor layers do not need to be removed; each test piece consisted of an insulating sheet cut along a plane perpendicular to the axis of the conductor using a sharp blade. The cores of the unsheathed flat cord should not be separated, and if the insulation has embossed marking indentations, the test piece should take a section containing the markings.
The step 1.2 comprises the following steps: firstly, removing all elements inside and outside the sheath, and cutting a thin sheet by a blade along a plane vertical to the axis of the cable; if the jacket is provided with the impression mark dent, the test piece should take a section containing the mark; secondly, when the inner side of the test piece is circular, 6 points are measured in the standard radial direction; if the inner circular surface of the test piece is irregular or not smooth in nature, 6 points are measured radially at the thinnest part of the sheath according to the standard; when a conductor is arranged on the inner side of the test piece to form a deep groove, the radial measurement is carried out on the bottom of each groove according to the standard; for the sheathed flat cord, it should be measured in the direction parallel to the minor axis and the major axis of the cross section of each insulated wire core, respectively, as a standard, and it is necessary to measure a point at the thinnest point; the six-core and the following sheathed flat cables are required to be as follows: measuring at both ends of the arc along the long axis of the cross section, and measuring at the first and last insulated wire cores at both flat sides; if the thinnest thickness is not among the several measurements, the thickness measurement in the direction of the thinnest point and the opposite direction should be increased; and finally, averaging the numerical values obtained in the previous step and accurately obtaining the numerical values 2 bits after the decimal point.
The step 1.3 comprises the following steps: when the outer diameter of the cable is not more than 25mm, respectively measuring in two mutually perpendicular directions by using a micrometer or a projector; when the outer diameter of the cable exceeds 25mm, measuring the circumference of the cable by using a measuring belt, and then calculating the diameter; the flat cable is measured along the major and minor axes of the cross-section with a micrometer or projector.
In order to comprehensively test the mechanical properties of the cable, preferably, the step 2 includes: cutting the wire core sample into small sections of 100mm, drawing out the conductor, removing all the outer protective layers, marking each tubular sample, and before an aging experiment, storing all the samples at the temperature of 18-28 ℃ for 3h while avoiding direct sunlight; aging the test piece by using a natural ventilation oven and a pressure ventilation oven, wherein air flows through the surface of the test piece in the treatment process and is discharged from the top of the oven, and the replacement frequency of all air in the oven is not less than 8 times and not more than 20 times per hour at the specified aging temperature; before the tensile test, all the test pieces are stored for 3h at the temperature of 18-28 ℃, then the tensile test is carried out on the test pieces by using a tensile tester, wherein the moving speed of a chuck of the tensile tester is 200-300mm/min, and the maximum tensile force is measured and recorded during the test.
Further, the step 3 comprises: conductor resistance inspection, product cable voltage test, insulation wire core voltage test and insulation resistance detection.
The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.
It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition.
In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.
Claims (7)
1. A method of cable testing, comprising:
step 1, measuring the size of a cable;
step 2, testing the mechanical property of the cable;
and 3, testing the electrical performance of the cable.
2. The cable detection method according to claim 1, wherein step 1 comprises:
step 1.1, measuring the insulation thickness;
step 1.2, measuring the thickness of the sheath;
and 1.3, measuring the ovality of the external dimension seam allowance.
3. The method of claim 2, wherein step 1.1 comprises preparing the sample, removing all of the sheath from the insulation, extracting the conductor and the barrier; if the inner and outer semiconductor layers are adhered together with the insulation, the inner and outer semiconductor layers do not need to be removed; each test piece consisted of an insulating sheet cut along a plane perpendicular to the axis of the conductor using a sharp blade. The cores of the unsheathed flat cord should not be separated, and if the insulation has embossed marking indentations, the test piece should take a section containing the markings.
4. The cable detection method according to claim 2, wherein the step 1.2 comprises: firstly, removing all elements inside and outside the sheath, and cutting a thin sheet by a blade along a plane vertical to the axis of the cable; if the jacket is provided with the impression mark dent, the test piece should take a section containing the mark; secondly, when the inner side of the test piece is circular, 6 points are measured in the standard radial direction; if the inner circular surface of the test piece is irregular or not smooth in nature, 6 points are measured radially at the thinnest part of the sheath according to the standard; when a conductor is arranged on the inner side of the test piece to form a deep groove, the radial measurement is carried out on the bottom of each groove according to the standard; for the sheathed flat cord, it should be measured in the direction parallel to the minor axis and the major axis of the cross section of each insulated wire core, respectively, as a standard, and it is necessary to measure a point at the thinnest point; the six-core and the following sheathed flat cables are required to be as follows: measuring at both ends of the arc along the long axis of the cross section, and measuring at the first and last insulated wire cores at both flat sides; if the thinnest thickness is not among the several measurements, the thickness measurement in the direction of the thinnest point and the opposite direction should be increased; and finally, averaging the numerical values obtained in the previous step and accurately obtaining the numerical values 2 bits after the decimal point.
5. The cable detection method according to claim 2, wherein the step 1.3 comprises: when the outer diameter of the cable is not more than 25mm, respectively measuring in two mutually perpendicular directions by using a micrometer or a projector; when the outer diameter of the cable exceeds 25mm, measuring the circumference of the cable by using a measuring belt, and then calculating the diameter; the flat cable is measured along the major and minor axes of the cross-section with a micrometer or projector.
6. The cable detection method of claim 1, wherein the step 2 comprises: cutting the wire core sample into small sections of 100mm, drawing out the conductor, removing all the outer protective layers, marking each tubular sample, and before an aging experiment, storing all the samples at the temperature of 18-28 ℃ for 3h while avoiding direct sunlight; aging the test piece by using a natural ventilation oven and a pressure ventilation oven, wherein air flows through the surface of the test piece in the treatment process and is discharged from the top of the oven, and the replacement frequency of all air in the oven is not less than 8 times and not more than 20 times per hour at the specified aging temperature; before the tensile test, all the test pieces are stored for 3h at the temperature of 18-28 ℃, then the tensile test is carried out on the test pieces by using a tensile tester, wherein the moving speed of a chuck of the tensile tester is 200-300mm/min, and the maximum tensile force is measured and recorded during the test.
7. The cable detection method of claim 1, wherein the step 3 comprises: conductor resistance inspection, product cable voltage test, insulation wire core voltage test and insulation resistance detection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911232362.2A CN110986852A (en) | 2019-12-05 | 2019-12-05 | Cable detection method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911232362.2A CN110986852A (en) | 2019-12-05 | 2019-12-05 | Cable detection method |
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| CN110986852A true CN110986852A (en) | 2020-04-10 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911232362.2A Pending CN110986852A (en) | 2019-12-05 | 2019-12-05 | Cable detection method |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112903449A (en) * | 2021-01-22 | 2021-06-04 | 福建省南平南线电力电缆有限公司 | Intelligent detection device for performance of cable sheath material and online test method thereof |
| CN113125224A (en) * | 2021-04-14 | 2021-07-16 | 海检检测有限公司 | Test piece of cable target layer, test piece manufacturing method and thickness measuring method |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103439611A (en) * | 2013-08-31 | 2013-12-11 | 安徽省电力科学研究院 | Electric wire and cable conductivity, tensile strength and aging comprehensive testing device |
-
2019
- 2019-12-05 CN CN201911232362.2A patent/CN110986852A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103439611A (en) * | 2013-08-31 | 2013-12-11 | 安徽省电力科学研究院 | Electric wire and cable conductivity, tensile strength and aging comprehensive testing device |
Non-Patent Citations (2)
| Title |
|---|
| 梁道俊: "电线电缆检测与质量控制重点探讨", 《中华民居》 * |
| 韩素玉: "《功能材料》", 30 November 2018, 中国建材工业出版社 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112903449A (en) * | 2021-01-22 | 2021-06-04 | 福建省南平南线电力电缆有限公司 | Intelligent detection device for performance of cable sheath material and online test method thereof |
| CN113125224A (en) * | 2021-04-14 | 2021-07-16 | 海检检测有限公司 | Test piece of cable target layer, test piece manufacturing method and thickness measuring method |
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Application publication date: 20200410 |