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CN-121994640-A - Method and device for detecting corrosion resistance of oil-proof product of enamelled copper wire

CN121994640ACN 121994640 ACN121994640 ACN 121994640ACN-121994640-A

Abstract

The invention relates to the technical field of corrosion detection and discloses a method and a device for detecting the corrosion resistance of an enamelled copper wire, wherein the method comprises the steps of selecting two enamelled copper wires, removing a coating layer on one enamelled copper wire, respectively weighing the two enamelled copper wires, and bending the two enamelled copper wires into a U shape with the same size; two enamelled copper wires are respectively communicated with a power supply and then immersed into a tank body filled with oil; heating and stirring oil liquid, switching on a power supply, cleaning the oil liquid on two enamelled copper wires after the test is finished, weighing again, calculating the weight change rate before and after the test, observing the two enamelled copper wires by using amplifying observation equipment, and judging that the corrosion resistance of the enamelled copper wires with/without the coating layer is good when the weight change rate of the enamelled copper wires without the coating layer is less than or equal to 1%, the weight change rate of the enamelled copper wires without the coating layer is less than or equal to 5% and the bending part is not corroded.

Inventors

  • LIU SHOUJIANG
  • GAO TE
  • ZHANG XIAOJU
  • ZHANG XIAOTIAN
  • YANG HONGWEI

Assignees

  • 陕西法士特汽车传动集团有限责任公司

Dates

Publication Date
20260508
Application Date
20260122

Claims (8)

  1. 1. The method for detecting the corrosion resistance of the enameled copper wire to the oil is characterized by comprising the following steps of: Selecting two enamelled copper wires with the same length, removing a coating layer on one enamelled copper wire, weighing the two enamelled copper wires respectively, and bending the two enamelled copper wires into U-shaped with the same size; the two enamelled copper wires are respectively communicated with a power supply, and then are immersed into a tank body filled with oil liquid, and the tank body is sealed; Heating the oil in the tank body, switching on the power supply of the two enamelled copper wires, and stirring the oil in the tank body; Weighing the two enamelled copper wires after the test is finished, and calculating the weight change rate of the two enamelled copper wires relative to the weight change rate before the test; When the weight change rate of the enamelled copper wire without the coating layer is less than or equal to 1 percent, the weight change rate of the enamelled copper wire without the coating layer is less than or equal to 5 percent, and the bending part is not corroded, the corrosion resistance is considered to be good.
  2. 2. The method for detecting the corrosion resistance of the enameled copper wire to oil is characterized in that oil in the tank body is heated to 140-160 ℃ in the testing process.
  3. 3. The method for detecting the corrosion resistance of an enameled copper wire according to claim 1, wherein the current is 4 mA-6 mA in the test process.
  4. 4. The method for detecting the corrosion resistance of an enameled copper wire according to claim 1 is characterized in that the test time is 230-250 hours in the test process.
  5. 5. The method for detecting the corrosion resistance of an enameled copper wire according to claim 1, wherein after the test is finished, two enameled copper wires are cleaned by using NY-120 solvent gasoline, the two enameled copper wires are sucked by using oil-absorbing paper, and then weighing measurement and microscopic morphology observation are carried out.
  6. 6. The method for detecting the oil corrosion resistance of an enameled copper wire according to claim 1, wherein the accuracy of the method is 0.1mg when two enameled copper wires are weighed before and after the test.
  7. 7. The method for detecting the corrosion resistance of the enamelled copper wire to the oil is characterized in that observation equipment is a scanning electron microscope, and the acceleration voltage of the scanning electron microscope is 15+/-5 kV, the electron beam current is 100+/-10 mu A, and the amplification factor is 400-600 times during observation.
  8. 8. The device for detecting the corrosion resistance of an enameled copper wire to oil according to claim 1, comprising: The tank body is used for containing oil; the sealing cover is detachably connected to the groove body; The two wiring boards are oppositely penetrated on the sealing cover, and a plurality of binding posts are oppositely arranged on the upper and lower wiring boards of the sealing cover respectively; The heating pipe is wound in the side wall of the tank body and is used for heating the oil in the tank body; the electromagnetic stirrer is arranged in the tank body and is used for stirring oil in the tank body.

Description

Method and device for detecting corrosion resistance of oil-proof product of enamelled copper wire Technical Field The invention relates to the technical field of corrosion detection, in particular to an enameled copper wire oil corrosion resistance evaluation device and method. Background The oil-cooled motor has become a mainstream technical scheme of new energy vehicles because of higher power density. For effective insulation, the enameled rectangular copper wire for the oil-cooled motor is usually made by wrapping polyimide or polyamide imide on the surface of the rectangular copper wire, and in actual use, the enameled rectangular copper wire needs to be bent to form a motor hairpin, microcracks are easy to generate at the bent part, and when the enameled rectangular copper wire is in direct contact with cooling oil of the motor, when polyimide and oil are poor in compatibility, the oil possibly penetrates through an insulating layer or microcracks to be in direct contact with a copper body, and at the moment, active components in the oil possibly corrode the surface of the copper, so that insulation failure is caused, and therefore scientific evaluation of the corrosion capability of oil-proof products of the enameled wire is very important. At present, the conventional combination of directly soaking, putting the enameled wire into an environmental bin and performing high-low temperature impact is generally adopted for verifying the oil corrosion resistance of the enameled wire in the industry, namely, firstly, completely immersing a wire sample into specified oil, then performing impact experiments according to preset high-low temperature, taking out a sample after the period is finished, and visually observing whether cracking or corrosion and other phenomena occur in the enameled copper wire by an inspector. The whole process lacks quantitative indexes, the judgment result highly depends on personal experience, subjectivity is high, slight damage and early failure are difficult to accurately distinguish, and the mode cannot meet the increasingly severe requirements of a high-end motor and a new energy automobile driving system. Disclosure of Invention The invention provides a method and a device for detecting the oil corrosion resistance of an enamelled copper wire, which are used for solving the defects in the prior art. The technical scheme of the invention is that the method for detecting the corrosion resistance of the enamelled copper wire to the oil comprises the following steps: Selecting two enamelled copper wires with the same length, removing a coating layer on one enamelled copper wire, weighing the two enamelled copper wires respectively, and bending the two enamelled copper wires into U-shaped with the same size; the two enamelled copper wires are respectively communicated with a power supply, and then are immersed into a tank body filled with oil liquid, and the tank body is sealed; Heating the oil in the tank body, switching on a power supply, and stirring the oil in the tank body, taking out two enamelled copper wires after the test is finished, and cleaning the oil on the two enamelled copper wires; Weighing the two enamelled copper wires after the test is finished, and calculating the weight change rate of the two enamelled copper wires relative to the weight change rate before the test; When the weight change rate of the enamelled copper wire without the coating layer is less than or equal to 1 percent, the weight change rate of the enamelled copper wire without the coating layer is less than or equal to 5 percent, and the bending part is not corroded, the corrosion resistance is considered to be good. In at least one embodiment of the invention, the oil in the tank is heated to 140-160 ℃ during the testing process. In at least one embodiment of the present invention, the current is made to be 4mA to 6mA during the test. In at least one embodiment of the present invention, the test time 230h to 250h is maintained during the test. In at least one embodiment of the present invention, after the test is completed, two of the enameled copper wires are cleaned with NY-120 solvent gasoline, and the two enameled copper wires are blotted dry with oil absorbing paper, followed by weighing measurement and microscopic morphology observation. In at least one embodiment of the present invention, the two enameled copper wires are weighed to the nearest 0.1mg before and after testing. In at least one embodiment of the invention, the observation equipment is a scanning electron microscope, and the acceleration voltage of the scanning electron microscope is 15+/-5 kV, the electron beam current is 100+/-10 mu A, and the amplification factor is 400-600 times during observation. The oil tank comprises a tank body, a sealing cover, two pairs of wiring boards, heating pipes and an electromagnetic stirrer, wherein the tank body is used for containing oil, the sealing cover is detachably connected to t