A method for evaluating the quality of resistance welding seams of cold-rolled plates

Abstract

The present invention discloses a method for evaluating the quality of resistance weld seams on cold-rolled sheet metal, comprising the following steps: S1. Disposing a lens above the weld seam; S2. Disposing a dichroic spectroscope to the right of the lens; S3. Infrared detectors I and II correspondingly receive infrared bands from narrowband filters I and II; S4. A microprocessor receives digital signals of radiance from two different infrared bands and calculates the temperature of the weld using a colorimetric method; S5. Constructing a temperature curve of the weld seam based on the temperature values ​​of different weld seams; S6. Using the temperature curve to evaluate the weld. The present method provides a fast and convenient method for evaluating the quality of resistance weld seams on cold-rolled sheet metal, simplifies the testing process, and improves work efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of welding, and in particular relates to a method for evaluating the quality of resistance welding seams of cold-rolled plates. Background Art

[0002] With the rapid development of aerospace, transportation, and marine engineering, higher requirements are placed on welding technology. The most direct way to improve welding level is to implement strict testing of welding quality. However, the current testing methods usually require a lot of manpower and material resources and take a long time.

[0003] A Chinese patent specification discloses an intelligent online weld detection device based on multi-source information fusion (publication number CN 109483107 A). This device obtains high-quality, time-varying infrared imaging information based on the residual heat of the weld. It uses an infrared array sensor and a visible light camera to capture real-time infrared and visible light videos of the weld during the welding process. The device then fuses and intelligently identifies the two types of video information through a video information acquisition module and an intelligent processing module. This information, including weld width, center trajectory, weld texture, and surface temperature distribution, is then acquired, and weld quality evaluation is performed using a deep learning algorithm. This device provides decision support for welding process evaluation by constructing a quality evaluation database for the entire welding process. However, the entire detection process is cumbersome and time-consuming, hindering rapid and convenient evaluation of welding quality. Summary of the Invention

[0004] 1. Technical Problems to be Solved

[0005] The present invention provides a method for evaluating the quality of resistance weld seams of cold-rolled plates, the purpose of which is to provide a fast and convenient evaluation method for detecting the quality of resistance weld seams of cold-rolled plates.

[0006] 2. Technical Solution

[0007] In order to achieve the above object, the method adopted by the present invention specifically comprises the following steps:

[0008] S1. Place a lens on the upper part of the weld and focus the lens on the weld to receive infrared radiation energy from the weld.

[0009] S2. A dichroic beam splitter is arranged on the right side of the lens. The transmitted light of the dichroic beam splitter includes all the wavelengths of the narrowband filter I, and the reflected light of the dichroic beam splitter includes all the wavelengths of the narrowband filter II.

[0010] S3, infrared detector I receives the infrared band from narrowband filter I and converts it into an electrical signal and inputs it into analog-to-digital converter I, infrared detector II receives the infrared band from narrowband filter II and converts it into an electrical signal and inputs it into analog-to-digital converter II;

[0011] S4, the microprocessor receives the digital signals of radiance of two different infrared bands and calculates the temperature of the soldering point using colorimetry;

[0012] S5. The temperature change curve of the weld is formed by the temperature values ​​of different welding points and displayed on the display;

[0013] S6. Use the temperature change curve to evaluate welding:

[0014] 1) When the welding heat state is too low and the temperature is ≤700℃, re-welding is necessary;

[0015] 2) When the temperature is >700°C and <1200°C, and the temperature change per unit length is greater than 200°C, it is determined to be a suspicious weld and a hammer test is required on the weld;

[0016] 3) When the temperature is 1200℃ and the temperature change per unit length is less than 30℃, it is determined to be a good weld and there is no need to perform a hammer test on the weld;

[0017] 4) When the temperature is 1000℃ and the temperature change per unit length is less than 100℃, it is determined to be spatter welding and the weld is required to be visually inspected.

[0018] Preferably, in step S2, the wavelength band of the narrowband filter I is 0.95-1.1 μm, and the wavelength band of the narrowband filter II is 0.75-1.1 μm.

[0019] Furthermore, the lens, dichroic spectroscope, narrowband filter I, narrowband filter II, infrared detector I, analog-to-digital converter I, infrared detector II, analog-to-digital converter II, microprocessor, and display move synchronously with the welding machine as a whole.

[0020] Furthermore, the weld is located between an upper welding wheel and a lower welding wheel, the upper welding wheel rotates counterclockwise, and the lower welding wheel rotates clockwise.

[0021] 3. Beneficial Effects

[0022] The cold-rolled plate resistance welding seam quality assessment method of the present invention provides a fast and convenient assessment method for detecting the quality of the cold-rolled plate resistance welding seam, simplifies the detection process, and improves work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of an application device of the cold-rolled plate resistance welding weld quality assessment method of the present invention.

[0024] Figure 2 The present invention is a flow chart of the cold-rolled plate resistance welding weld quality evaluation method. DETAILED DESCRIPTION

[0025] The technical solution of the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can have a clearer understanding.

[0026] Example

[0027] like Figure 1 As shown, the application device of this embodiment includes a lens 3, a dichroic spectrometer 5, a narrowband filter I 6, a narrowband filter II 8, an infrared detector I 7, an analog-to-digital converter I, an infrared detector II 9, an analog-to-digital converter II, a microprocessor, and a display. The application device as a whole moves synchronously with the welding machine; the welding machine includes an upper welding wheel 1 and a lower welding wheel 2. The upper welding wheel rotates counterclockwise, and the lower welding wheel rotates clockwise. The weld seam 4 is located between the upper welding wheel and the lower welding wheel.

[0028] like Figure 2 As shown, the cold-rolled plate resistance welding weld quality assessment method of this embodiment adopts the following specific steps:

[0029] S1. Place lens 3 above the weld and focus the lens on weld 4 to receive infrared radiation energy from the weld.

[0030] S2. A dichroic spectroscope 5 is provided on the right side of the lens. The transmitted light of the dichroic spectroscope includes all wavelength bands of the narrowband filter I 6, and the reflected light includes all wavelength bands of the narrowband filter II 8.

[0031] As a preferred embodiment of this embodiment, the wavelength range of the narrowband filter I (6) is 0.95-1.1 μm, and the wavelength range of the narrowband filter II (8) is 0.75-1.1 μm;

[0032] S3, infrared detector I 7 receives the infrared band from narrowband filter I and converts it into an electrical signal and inputs it into analog-to-digital converter I, infrared detector II 9 receives the infrared band from the narrowband filter II and converts it into an electrical signal and inputs it into analog-to-digital converter II;

[0033] S4, the microprocessor receives the digital signals of radiance of two different infrared bands and calculates the temperature of the soldering point using colorimetry;

[0034] S5. The temperature change curve of the weld is formed by the temperature values ​​of different welding points and displayed on the display;

[0035] S6. Use the temperature change curve to evaluate welding:

[0036] 1) When the welding heat state is too low and the temperature is ≤700℃, re-welding is necessary;

[0037] 2) When the temperature is >700°C and <1200°C, and the temperature change per unit length is greater than 200°C, it is determined to be a suspicious weld and a hammer test is required on the weld;

[0038] 3) When the temperature is 1200℃ and the temperature change per unit length is less than 30℃, it is determined to be a good weld and there is no need to perform a hammer test on the weld;

[0039] 4) When the temperature is 1000℃ and the temperature change per unit length is less than 100℃, it is determined to be spatter welding and the weld is required to be visually inspected.

[0040] The cold-rolled plate resistance welding seam quality assessment method of the present invention provides a fast and convenient assessment method for detecting the quality of the cold-rolled plate resistance welding seam, simplifies the detection process, and improves work efficiency.

[0041] The present invention is not limited to the above-mentioned specific embodiments. Various improvements made by those skilled in the art to the technical solution based on the concept of the present invention should fall within the scope of protection required by the present invention.

Claims

1. A method for evaluating the quality of cold-rolled plate resistance welding seams, characterized in that: The quality of the weld is evaluated through feedback of the weld temperature field, which specifically includes the following steps: S1. A lens (3) is arranged above the weld, and the focus of the lens is placed on the weld (4), thereby receiving infrared radiation energy from the weld; S2. A dichroic spectroscope (5) is provided on the right side of the lens, wherein the transmitted light of the dichroic spectroscope includes all the wavelengths of the narrowband filter I (6), and the reflected light of the dichroic spectroscope includes all the wavelengths of the narrowband filter II (8); S3, infrared detector I (7) receives the infrared band from narrowband filter I and converts it into an electrical signal and inputs it into analog-to-digital converter I, infrared detector II (9) receives the infrared band from narrowband filter II and converts it into an electrical signal and inputs it into analog-to-digital converter II; S4, the microprocessor receives the digital signals of radiance of two different infrared bands and calculates the temperature of the soldering point using colorimetry; S5. The temperature change curve of the weld is formed by the temperature values ​​of different welding points and displayed on the display; S6. Use the temperature change curve to evaluate welding: 1) When the welding heat state is too low and the temperature is ≤700℃, re-welding is necessary; 2) When the temperature is >700°C and <1200°C, and the temperature change per unit length is greater than 200°C, it is determined to be a suspicious weld and a hammer test is required on the weld; 3) When the temperature is 1200℃ and the temperature change per unit length is less than 30℃, it is determined to be a good weld and there is no need to perform a hammer test on the weld; 4) When the temperature is 1000℃ and the temperature change per unit length is less than 100℃, it is determined to be spatter welding and the weld is required to be visually inspected.

2. The method for evaluating the quality of cold-rolled sheet resistance welding seams according to claim 1, wherein: In step S2, the wavelength band of the narrowband filter I (6) is 0.95-1.1 μm, and the wavelength band of the narrowband filter II (8) is 0.75-1.1 μm.

3. The method for evaluating the quality of cold-rolled sheet resistance welding seams according to claim 2, wherein: The lens, dichroic spectroscope, narrowband filter I, narrowband filter II, infrared detector I, analog-to-digital converter I, infrared detector II, analog-to-digital converter II, microprocessor and display move synchronously with the welding machine as a whole.

4. The method for evaluating the quality of cold-rolled sheet resistance welding seams according to claim 3, wherein: The welding seam (4) is located between an upper welding wheel (1) and a lower welding wheel (2); the upper welding wheel rotates counterclockwise, and the lower welding wheel rotates clockwise.

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