Method for complex defect detection and additive and subtractive material repair of track key parts

Abstract

The invention belongs to the field of defect detection and repair, and discloses a method for complex defect detection and additive and subtractive repair of track key parts, which comprises the following steps of: detecting the track key parts by using detection equipment to obtain defect characteristics of the parts; according to the types, sizes and position characteristics of the defects, a part subtractive machining area and a repairing method are determined; a machining method is adopted to remove materials in the subtractive machining area of the part; a line laser scanner is used for scanning the defect area of the key part of the rail after material reduction machining, a three-dimensional model of the area to be repaired is established, and a laser material increase repairing path of the area to be repaired is determined; a laser additive repairing technology is adopted to complete repairing of defect areas of the key parts of the rail; and the repaired surface of the rail key part is polished, and the outline morphology of the part is recovered. According to the method, high-efficiency and high-precision repair of complex defects of key parts of the track can be achieved, and the influence on undamaged areas is small.

Description

Technical Field

[0001] The present invention relates to the field of defect detection and repair, and particularly to a method for complex defect detection and additive and subtractive repair of key components of tracks. Background Art

[0002] Key components of tracks such as steel rails and fish plates work under the condition of high-frequency alternating loads for a long time, and are prone to defects such as depressions, spalling and cracks. If these defects cannot be detected and repaired in time, it will seriously threaten the operation safety of the rail transit system. Ultrasonic detection and line laser scanning are simple to operate and have high resolution, and can achieve high-precision detection of complex defects of key components of tracks and obtain accurate defect characteristics. The laser additive repair technology deposits powder or wire layer by layer in the area to be repaired by laser, and has advantages such as high repair efficiency and excellent performance of the repaired parts, and can effectively repair the defects of key components of tracks. However, in the process of laser additive repair of defects of key components of tracks, crack defects are more complex in shape than other defects, and the direct repair effect is poor. It is necessary to first use a subtractive processing method to remove the material in the defect area to obtain a relatively regular area to be repaired, and then complete the defect repair through the laser additive repair technology. Among them, the selection of the laser additive repair technology and the determination of the subtractive processing area have an important impact on the repair quality of complex defects of key components of tracks. Therefore, it is urgent to develop a method for complex defect detection and additive and subtractive repair of key components of tracks to achieve efficient and high-quality repair of complex defects of key components of tracks. Summary of the Invention

[0003] The purpose of the present invention is to obtain the defect characteristics of key components of tracks through a detection device, calculate the subtractive processing area V of the components and use a machining method to remove the material in this area, establish a three-dimensional model of the area to be repaired, determine the laser additive repair path, and use the laser additive repair technology to repair the defect area of the components, and provide a method for complex defect detection and additive and subtractive repair of key components of tracks.

[0004] The technical solution of the present invention is as follows: A method for complex defect detection and additive and subtractive repair of key components of tracks includes the following steps:

[0005] Step 1: Use a detection device to detect key components of tracks and obtain the defect characteristics of the components;

[0006] Step 2: Determine the subtractive processing area V of the components and the repair method according to the type, size and position characteristics of the defects;

[0007] Step 3: Use a machining method to remove the material in the subtractive processing area V of the components;

[0008] Step 4: Use a line laser scanner to scan the defective area of the key components of the track after subtractive machining, establish a three-dimensional model of the area to be repaired, and determine the laser additive repair path for the area to be repaired.

[0009] Step 5: Adopt laser additive repair technology to complete the repair of the defective area of the key components of the track.

[0010] Step 6: Grind the surface of the repaired key components of the track to restore the contour and morphology of the components.

[0011] Further, in Step 1, the detection equipment consists of a surface defect detection device and an internal defect detection device. During the detection process, the surface defects and internal defects are detected synchronously. A line laser scanner is selected as the surface defect detection device to detect the depression and spalling defects on the surface of the components and obtain their size and position characteristics; a phased array ultrasonic flaw detector is selected as the internal defect detection device to detect the crack defects on the surface and inside of the components and obtain their size and position characteristics.

[0012] Further, in Step 2, based on the defect characteristics obtained by the surface defect detection device and the internal defect detection device, for the defective areas of depression and spalling on the surface of the components, the powder-fed laser additive repair technology is directly used for repair; for the crack defective areas on the surface and inside of the components, it is judged whether they can be repaired according to the size and position characteristics of the cracks. If they can be repaired, it is necessary to further confirm the subtractive machining area V of the components for machining, and select the wire-fed laser additive repair technology or the powder-fed laser additive repair technology according to the size of the subtractive machining area V of the components.

[0013] Further, the subtractive machining area V of the components is evenly divided into n layers along the height direction, and the subtractive machining areas V1, V2, V3...V of the components are calculated layer by layer. n , during the calculation process, it is assumed that the subtractive machining areas V1, V2, V3...V of each layer n are all straight cylinders, and the calculation process of the subtractive machining area V of the components is as follows:

[0014] According to the obtained size and position characteristics of the crack, establish a three-dimensional model of the crack. The height H of the subtractive machining area V of the components is determined according to the highest point Z of the upper surface of the components max and the lowest point Z of the crack min :

[0015] H = Z max - Z min

[0016] In order to minimize the impact of subtractive machining on the undamaged areas of components as much as possible, a smaller subtractive machining area V of the component is calculated on the premise of ensuring the complete removal of the defect area. The three-dimensional model of the crack is evenly divided into n layers along the height direction. The minimum circumscribed circle is made within each layer of slice so that it can completely enclose the crack area. The obtained circumscribed circles are denoted as S1, S2, S3...S n , where S1 corresponds to the minimum circumscribed circle of the slice at the lowest point of the crack, and S n corresponds to the minimum circumscribed circle of the slice at the upper surface of the component where the crack is located;

[0017] In order to ensure the quality of subsequent laser additive repair and ensure that the projected area of the lower-layer subtractive machining area on the upper-layer slice is completely surrounded by the upper-layer subtractive machining area, the minimum circumscribed circles S1, S2, S3...S of each layer of slice are compared and accumulated layer by layer n to obtain a more reasonable subtractive machining area. The bottom surfaces of the subtractive machining areas V1, V2, V3...V of each layer of slice are denoted as S'1, S'2, S'3...S n ', and the projected areas of the subtractive machining areas of each layer of slice on the upper-layer slice are denoted as T1, T2, T3...T n , and the calculation process of the bottom surfaces S'1, S'2, S'3...S n-1 ' is as follows: n The bottom surface S'1 of the subtractive machining area V1 of the first-layer slice is the minimum circumscribed circle S1 of the slice at the lowest point of the crack, that is, S'1 = S1;

[0018] The projected area T1 is obtained by projecting the bottom surface S'1 of the subtractive machining area V1 of the first-layer slice onto the minimum circumscribed circle S2 of the second-layer slice. If the minimum circumscribed circle S2 can completely enclose the projected area T1, then the bottom surface S'2 of the subtractive machining area V2 of the second-layer slice is the minimum circumscribed circle S2, that is, S'2 = S2. If the minimum circumscribed circle S2 cannot completely enclose the projected area T1, then the bottom surface S'2 of the subtractive machining area V2 of the second-layer slice is the combined area of the minimum circumscribed circle S2 and the projected area T1, that is, S'2 = S2 + T1;

[0019] The projected area T2 is obtained by projecting the bottom surface S'2 of the subtractive machining area V2 of the second-layer slice onto the minimum circumscribed circle S3 of the third-layer slice. If S'3 = S3, if the minimum circumscribed circle S3 cannot completely enclose the projected area T2, then the bottom surface S'3 of the subtractive machining area V3 of the third-layer slice is the combined area of the minimum circumscribed circle S3 and the projected area T2, that is, S'3 = S3 + T2;

[0020] And so on, the subtractive machining areas V1, V2, V3...V of each layer of slice are obtained

[0021] n ​The bottom surfaces S'1, S'2, S'3... S n ', then the material removal processing areas V1, V2, V3... V of each layer of slices n are straight cylinders with the bottom surfaces being S'1, S'2, S'3... S n ', and the height being H / n. The material removal processing area V of the component is the accumulation of the material removal processing areas V1, V2, V3... V of each layer of slices, that is, V = V1 + V2 + V3 +... + V n . n .

[0022] Furthermore, in step 5, the area to be repaired is repaired according to the determined laser additive repair path. Among them, for the defects of depression and spalling, the powder feeding laser additive repair technology is used for repair. For the crack defects, a suitable additive manufacturing technology is selected according to the size of the material removal processing area V of the component. If the material removal processing area V of the component is large, the wire feeding laser additive repair technology is used to improve the repair efficiency. If the material removal processing area V of the component is small, the powder feeding laser additive repair technology is used to improve the repair accuracy.

[0023] Compared with the prior art, the above technical solution conceived by the present invention mainly has the following beneficial effects:

[0024] A method for detecting and additive / subtractive repair of complex defects of key components of tracks provided by the present invention uses a phased array ultrasonic flaw detector and a line laser scanner to detect the surface and internal defects of key components of tracks to obtain their size and position characteristics. On the premise of ensuring the complete removal of the defect area, a smaller material removal processing area V is calculated to reduce the impact of material removal processing on the undamaged area. For defects with different types, sizes and position characteristics, targeted laser additive repair technologies are used for repair to ensure the accuracy and efficiency of the repair of complex defects of key components of tracks. Description of the Drawings

[0025] Figure 1 is a flowchart of a method for detecting and additive / subtractive repair of complex defects of key components of tracks according to the present invention;

[0026] Figure 2 is a schematic diagram of the complex defect detection process according to the present invention;

[0027] Figure 3 is a schematic diagram of the additive / subtractive repair process according to the present invention;

[0028] In the figure: 1 - computer, 2 - phased array ultrasonic flaw detector, 3 - data line, 4 - line laser, 5 - line laser scanner, 6 - phased array probe, 7 - depression, 8 - spalling, 9 - crack, 10 - rail, 11 - material removal processing area V of the component, 12 - repaired defect area, 13 - polished defect area. Specific implementation manners

[0029] To make the technical problems, technical solutions, and advantages to be solved by the present invention clearer, the following will be described in detail with reference to the accompanying drawings and specific embodiments. The illustrative implementation manners of the present invention are only used to explain the present invention and are not intended to limit the present invention. The following uses several specific embodiments in combination with the accompanying drawings to further elaborate on the present invention.

[0030] Based on the detection and repair requirements of defects in key track components, the present invention provides a method for detecting and additive / subtractive repairing complex defects in key track components. In this embodiment, taking a steel rail 10 made of Q235 as an example, defects such as dents 7, spalling 8, and cracks 9 are detected and repaired using a laser additive / subtractive repair method. The process is as Figure 1 shown.

[0031] Step 1: Before using the detection equipment to detect defects, apply a coupling agent on the surface of the steel rail 10 to eliminate the interference of the air gap between the phased array probe 6 and the surface of the steel rail 10, so that ultrasonic waves can effectively enter the interior of the steel rail 10. Place the line laser scanner 5 above the steel rail 10, and the phased array probe 6 closely adheres to the surface of the steel rail 10. The line laser scanner 5 and the phased array probe 6 move along the length direction of the steel rail 10. Obtain the surface and internal defect characteristics of the entire section of the steel rail 10 through the line laser 4 and ultrasonic waves, and transmit the obtained defect characteristics to the computer 1 through the data line 3 for processing, as Figure 2 shown;

[0032] Step 2: According to the defect characteristics obtained by the surface defect detection equipment and the internal defect detection equipment, identify and classify the detected defects. According to the scanning results of the line laser scanner 5, it is found that there are dents 7 and spalling 8 defects on the surface of the steel rail. These defects are repaired using the powder feeding laser additive repair technology. According to the detection results of the phased array ultrasonic flaw detector 2, it is found that there is a crack 9 extending into the interior of the steel rail on the surface of the component. Analyze the size and position characteristics of the crack 9 through the computer 1 to determine that the crack 9 can be repaired. In order to repair the crack 9, it is necessary to first determine the subtractive machining area V11 of the component;

[0033] According to the accuracy of the laser additive repair equipment and the defect repair requirements, the subtractive machining area V11 of the component is evenly divided into n layers along the height direction, and the subtractive machining areas V1, V2, V3...V n of the component are calculated layer by layer. During the calculation process, it is assumed that the subtractive machining areas V1, V2, V3...V n of each layer are all straight cylinders. The calculation process of the subtractive machining area V11 of the component is as follows:

[0034] Based on the obtained size and position characteristics of crack 9, a three-dimensional model of crack 9 is established. The height H of the machining area V11 for component material removal is determined according to the highest point Z on the upper surface of the component max and the lowest point Z of the crack min as follows:

[0035] H = Z max - Z min

[0036] From the three-dimensional model of the crack, H = 10 mm is obtained. To minimize the impact of material removal machining on the undamaged area of the component as much as possible, a smaller machining area V for component material removal is calculated on the premise of ensuring complete removal of the defect area. The three-dimensional model of crack 9 is evenly divided into n layers along the height direction, and the height of each layer is H / n. The minimum circumscribed circle is made within each layer slice so that it can completely enclose the crack 9 area. The obtained circumscribed circles are denoted as S1, S2, S3... S n , where S1 corresponds to the minimum circumscribed circle of the slice at the lowest point of the crack, and S n corresponds to the minimum circumscribed circle of the slice at the highest point on the upper surface of the component. In this embodiment, n = 10 is taken, and the height of each layer H / n = 1 mm;

[0037] To ensure the subsequent additive repair quality and ensure that the projection area of the lower layer machining area for material removal is completely surrounded by the upper layer machining area for material removal, by comparing and accumulating the minimum circumscribed circles S1, S2, S3... S of each layer slice layer by layer 10 , a more reasonable machining area for material removal is obtained. The bottom surfaces of the machining areas V1, V2, V3... V 10 for each layer slice are denoted as S'1, S'2, S'3... S' 10 , and the projection areas of the machining areas for material removal of each layer slice on the upper layer slice are denoted as T1, T2, T3... T9. The calculation process of the bottom surfaces S'1, S'2, S'3... S' 10 is as follows:

[0038] The bottom surface S'1 of the machining area V1 of the first layer slice is the minimum circumscribed circle S1 of the slice at the lowest point of the crack, that is, S'1 = S1;

[0039] The projection area T1 is obtained by projecting the bottom surface S'1 of the machining area V1 of the first layer slice onto the minimum circumscribed circle S2 of the second layer slice. It is found that the minimum circumscribed circle S2 cannot completely enclose the projection area T1. The bottom surface S'2 of the machining area V2 of the second layer slice is the combined area of the minimum circumscribed circle S2 at the second layer slice and the projection area T1, that is, S'2 = S2 + T1;

[0040] The bottom surface S'2 of the material removal processing area V2 of the second layer slice is projected onto the minimum circumscribed circle S3 of the third layer slice to obtain a projection area T2. It is found that the minimum circumscribed circle S3 cannot completely enclose the projection area T2. Then, the bottom surface S'3 of the material removal processing area V3 of the third layer slice is the combined area of the minimum circumscribed circle S3 and the projection area T2 at the third layer slice, that is, S'3 = S3 + T2;

[0041] And so on, the material removal processing areas V1, V2, V3...V 10 of each layer slice are obtained, and the bottom surfaces S'1, S'2, S'3...S' 10 of them are obtained. Then, the material removal processing areas V1, V2, V3...V 10 of each layer slice are straight cylinders with bottom surfaces being S'1, S'2, S'3...S' 10 and a height of 1 mm. The component material removal processing area V11 is the accumulation of the material removal processing areas V1, V2, V3...V 10 of each layer slice, that is, V = V1 + V2 + V3 +... + V 10 . The calculated component material removal processing area V11 is relatively large, and the wire feeding laser additive repair technology is selected to repair this defect.

[0042] Step 3: Determine the machining process parameters according to the component material removal processing area V11, such as the cutter speed, cutting depth, and feed per tooth, remove the material within the component material removal processing area V11. After the material removal processing is completed, clean the processing area, and clean up the remaining waste materials and impurities, etc., to avoid affecting the subsequent laser additive repair quality, as Figure 3 shown;

[0043] Step 4: After completing the material removal processing and cleaning work, use the line laser scanner 5 to scan the surface profile of the rail again. Transmit the three-dimensional point cloud data of the depression 7, spalling 8, and the area to be repaired in the component material removal processing area V11 to the computer 1. The computer 1 establishes a three-dimensional model according to the three-dimensional point cloud data of the area to be repaired and determines the laser additive repair path of the area to be repaired;

[0044] Step 5: Repair the area to be repaired according to the determined laser additive repair path. For the defects of the depression 7 and spalling 8, the powder feeding laser additive repair technology is used for repair, and for the crack 9 defect, the wire feeding laser additive repair technology is used for repair, as Figure 3 shown. In this embodiment, the powder material and wire material are Q235. The laser power during powder feeding is 1000 W, the powder feeding speed is 15 g / min, the laser scanning speed during powder feeding is 7 mm / s, the laser power during wire feeding is 1100 W, the wire feeding speed is 20 mm / s, and the laser scanning speed during wire feeding is 40 mm / s;

[0045] Step 6: After repairing the defects such as the depression 7, spalling 8 and crack 9 by using the laser additive repair technology, there are differences in the surface roughness and profile between the surface of the repaired defect area 12 and the surface of the original rail 10. Use a grinding wheel, sandpaper, etc. to polish the surface of the repaired defect area 12 to restore the surface profile of the rail and obtain the polished defect area 13, as Figure 3 shown;

[0046] Through the above embodiments, the purpose, method and content of the present invention have been further described in detail. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the protection scope of the present invention. The present invention can be appropriately modified to be applied to other suitable scenarios in the welding field. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for detecting complex defects and additive and subtractive repair of key components of tracks, characterized in that, Including the following steps: Step 1: Use a detection device to detect key components of the track and obtain the defect characteristics of the components; Step 2: Determine the material removal processing area V of the component and the repair method according to the type, size and position characteristics of the defect; Step 3: Use a machining method to remove the material within the material removal processing area V of the component; Step 4: Use a line laser scanner to scan the defect area of the key track component after material removal, establish a three-dimensional model of the area to be repaired, and determine the laser additive repair path of the area to be repaired; Step 5: Use laser additive repair technology to complete the repair of the defect area of the key track component; Step 6: Grind the surface of the repaired key track component to restore the contour and morphology of the component.

2. A method for detecting complex defects and additive and subtractive repair of key track components according to claim 1, characterized in that, In Step 1, the detection device consists of a surface defect detection device and an internal defect detection device. During the detection process, the surface defects and internal defects are detected synchronously. A line laser scanner is selected as the surface defect detection device to detect the depression and spalling defects on the surface of the component and obtain their size and position characteristics; A phased array ultrasonic flaw detector is selected as the internal defect detection device to detect the crack defects on the surface and inside of the component and obtain their size and position characteristics.

3. A method for complex defect detection and additive and subtractive repair of key track components according to claim 1, characterized in that, In Step 2, based on the type, size and position characteristics of the defects obtained by the surface defect detection device and the internal defect detection device, for the depression and spalling defect areas on the surface of the component, the powder feeding laser additive repair technology is directly used for repair; for the crack defect areas on the surface and inside of the component, it is judged whether they can be repaired according to the size and position characteristics of the cracks. If they can be repaired, the material removal processing area V of the component for machining is further confirmed, and the wire feeding laser additive repair technology or the powder feeding laser additive repair technology is selected according to the size of the material removal processing area V of the component.

4. A method for detecting complex defects and additive and subtractive repair of key components of tracks according to claim 3, characterized in that, The subtractive machining area V of the component is evenly divided into n layers along the height direction, and the subtractive machining areas V1, V2, V3... V of the component are calculated layer by layer. n , assuming that the subtractive machining areas V1, V2, V3... V of each layer n are all straight cylinders during the calculation process, and the calculation process of the subtractive machining area V of the component is as follows: According to the obtained crack size and position characteristics, a three-dimensional model of the crack is established. The height H of the machining area V of the component is determined based on the highest point Z of the upper surface of the component max and the lowest point Z of the crack min as follows: H = Z max -Z min In order to minimize the impact of subtractive machining on the undamaged areas of components as much as possible, a smaller subtractive machining area V of the component is calculated on the premise of ensuring the complete removal of the defect area. The three-dimensional model of the crack is evenly divided into n layers along the height direction. The minimum circumscribed circle is made within each layer of the slice so that it can completely enclose the crack area. The obtained circumscribed circles are denoted as S1, S2, S3...S n , where S1 corresponds to the minimum circumscribed circle of the slice at the lowest point of the crack, and S n corresponds to the minimum circumscribed circle of the slice at the highest point of the upper surface of the component; To ensure the quality of subsequent laser additive repair and guarantee that the projection area of the lower subtractive machining area on the upper layer slice is completely surrounded by the upper subtractive machining area, by comparing and accumulating the minimum circumscribed circles S1, S2, S3...S of each layer slice layer by layer n , to obtain a more reasonable subtractive machining area of the component. The bottom surfaces of the subtractive machining areas V1, V2, V3...V of each layer slice are denoted as S′1, S′2, S′3...S′ n , and the projection areas of the subtractive machining areas of each layer slice on the upper layer slice are denoted as T1, T2, T3...T n , and the calculation process of the bottom surfaces S′1, S′2, S′3...S′ n-1 is as follows: n The calculation process is as follows: The bottom surface S′1 of the material removal processing area V1 of the first layer slice is the minimum circumscribed circle S1 of the slice at the lowest point of the crack, that is, S′1 = S1; Project the bottom surface S′1 of the material removal processing area V1 of the first layer slice onto the minimum circumscribed circle S2 of the second layer slice to obtain the projection area T1. If the minimum circumscribed circle S2 can completely enclose the projection area T1, the bottom surface S′2 of the material removal processing area V2 of the second layer slice is the minimum circumscribed circle S2, that is, S′2 = S2. If the minimum circumscribed circle S2 cannot completely enclose the projection area T1, the bottom surface S′2 of the material removal processing area V2 of the second layer slice is the combined area of the minimum circumscribed circle S2 and the projection area T1, that is, S′2 = S2 + T1; Project the bottom surface S′2 of the material removal processing area V2 of the second layer slice onto the minimum circumscribed circle S3 of the third layer slice to obtain the projection area T2. If the minimum circumscribed circle S3 can completely enclose the projection area T2, the bottom surface S′3 of the material removal processing area V3 of the third layer slice is the minimum circumscribed circle S3, that is, S′3 = S3. If the minimum circumscribed circle S3 cannot completely enclose the projection area T2, the bottom surface S′3 of the material removal processing area V3 of the third layer slice is the combined area of the minimum circumscribed circle S3 and the projection area T2, that is, S′3 = S3 + T2; And so on, the material removal regions V1, V2, V3... V of each layer of slices are obtained n The bottom surfaces S′1, S′2, S′3... S′ n Then, the material removal regions V1, V2, V3... V of each layer of slices n Are straight cylinders with bottom surfaces S′1, S′2, S′3... S′ n And height H / n. The material removal region V of the component is the sum of the material removal regions V1, V2, V3... V of each layer of slices n Accumulated, that is, V = V1 + V2 + V3 +... + V n .

5. A method for complex defect detection and additive and subtractive repair of key components of a track according to claim 1, characterized in that, In step 5, the area to be repaired is repaired according to the determined laser additive repair path. Among them, for the defects of depression and spalling, the powder feeding laser additive repair technology is used for repair. For the crack defects, a suitable laser additive repair technology is selected according to the size of the machining area V of the component. If the machining area V of the component is large, the wire feeding laser additive repair technology is used to improve the repair efficiency. If the machining area V of the component is small, the powder feeding laser additive repair technology is used to improve the repair accuracy.

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