Thin steel plate wire cut electrical discharge machining fixing method

Abstract

The invention discloses a thin steel plate wire cut electrical discharge machining fixing method, which belongs to the technical field of machining, and comprises the following steps: S1, stacking a preset number of steel plates, ensuring that the edges of the steel plates are aligned and are not staggered, and placing the steel plates on a clamp for fixing; s2, all the side faces of the steel plate are welded, the welding position is selected to be in a non-machining area of the steel plate, and welding seams are vertically arranged; s3, proper cooling treatment is carried out on the welding part; s4, before subsequent cutting machining is conducted, the stacking state of the steel plates is checked again, it is guaranteed that all the edges of the steel plates are aligned and are not dislocated, and the phenomenon that the steel plates are loosened is avoided; and if the inspection is not qualified, returning to S1. The problems that during small-batch linear cutting production of thin steel plates, the steel plates clamped through a clamp are prone to loosening, the steel plates move relatively, and the size of parts is out of tolerance can be solved; meanwhile, the problem that a clamp affects fixation of the steel plate on an electric spark linear cutting machine tool is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of machining, and in particular to a method for fixing thin steel plates by wire electrical discharge machining (WEDM). Background Art

[0002] During the scientific research and trial production of mechanical equipment, there are often parts made of thin steel plates with a thickness of less than 0.5 mm. For parts with this thickness, the stamping process is the most suitable. However, due to the uncertain state of the scientific research and trial production products, the risk of investing in molds for stamping is relatively high. Therefore, wire electrical discharge machining is generally used in the stages of scientific research and trial production and small batch production.

[0003] Wire electrical discharge machining has high machining accuracy but low efficiency. To improve the wire cutting efficiency, a fixture is usually used to clamp and fix a stack (dozens of pieces) of thin steel plates, and then cutting is carried out, which greatly improves the machining efficiency.

[0004] During wire electrical discharge machining, the steel plate to be cut needs to be fixed to the machine tool, usually by bolts. When using the existing technical solutions for machining, the fixture is prone to looseness, resulting in relative movement of the steel plate, which leads to out-of-tolerance cutting dimensions and scrapping of parts. At the same time, since the thin steel plate has been fixed by the fixture in advance, there is often no suitable position when fixing it to the wire electrical discharge machine tool, and a special tooling needs to be used for alignment. Moreover, during cutting. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method for fixing thin steel plates by wire electrical discharge machining, which can solve the problems that when small batch production of thin steel plates is carried out by wire cutting, the steel plates are prone to looseness when clamped by the fixture, resulting in relative movement of the steel plates and out-of-tolerance part dimensions; at the same time, it solves the problem that the fixture affects the fixing of the steel plate on the wire electrical discharge machine tool.

[0006] To solve the above technical problems, the technical solution adopted by the present invention is as follows: A method for fixing thin steel plates by wire electrical discharge machining includes the following steps: S1. Stack a preset number of steel plates, ensure that each side of each steel plate is aligned and there is no dislocation, and place them on the fixture for fixing; S2. Weld all sides of the steel plates, select the welding positions in the non-machining areas of the steel plates, and set the weld seams vertically; S3. Perform appropriate cooling treatment on the welded parts; S4. Before carrying out subsequent cutting machining, check the stacked state of the steel plates again to ensure that each side of each steel plate is aligned and there is no dislocation, and there is no looseness between the layers of steel plates; if the inspection is unqualified, return to S1.

[0007] A further improvement of the technical solution of the present invention lies in that: in S1, a positioning tool is used to assist the operation to ensure that the edge error of each steel plate is controlled within the threshold range.

[0008] A further improvement of the technical solution of the present invention lies in that: the positioning tool includes a positioning caliper and a laser alignment device.

[0009] A further improvement of the technical solution of the present invention lies in that: in S1, during the stacking process, a special cleaning agent and wiping tool are used to clean the surface of the steel plate to ensure that the contact surface during welding is clean and flat.

[0010] A further improvement of the technical solution of the present invention lies in that: in S2, the width of each weld seam is not less than 2 mm, and the distance between adjacent weld seams is not greater than 20 mm.

[0011] A further improvement of the technical solution of the present invention lies in that: in S2, after welding is completed, the welded part is inspected, and repair welding is carried out if necessary.

[0012] A further improvement of the technical solution of the present invention lies in that: in S3, the cooling treatment includes natural cooling and air cooling.

[0013] Due to the adoption of the above technical solution, the technical progress achieved by the present invention is as follows: 1. The welding fixation of the present invention can provide a strong connection force to ensure that the steel plate does not move relatively during the wire electrical discharge machining process. This not only improves the machining accuracy but also reduces the machining defects caused by insecure fixation.

[0014] 2. Compared with the traditional mechanical fixture, the welding fixation of the present invention does not require complex adjustment and frequent inspection, greatly simplifying the operation process.

[0015] 3. The welding fixation method of the present invention is applicable to steel plates of various thicknesses and sizes, having wide applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic diagram of fixing a thin steel plate with a fixture in the present invention; Figure 2 is a schematic diagram of the improved steel plate fixing method in the present invention; Wherein, 1. Fixture, 2. Steel plate, 3. Weld seam. DETAILED DESCRIPTION OF THE INVENTION

[0017] The following further describes the present invention in detail with reference to the drawings and embodiments: In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the present invention.

[0018] A method for fixing a thin steel plate by wire electrical discharge machining includes the following steps: S1. Stack a preset number of steel plates 2, ensure that each side of each steel plate 2 is aligned without dislocation, and place them on the fixture 1 for fixing; this step is the basis of the entire process, and the alignment accuracy directly affects the effects of subsequent welding and machining. Use a positioning tool (such as a positioning caliper or a laser alignment device) to assist the operation to ensure that the edge error of each steel plate 2 is controlled within a very small range. During the stacking process, attention should also be paid to the cleanliness of the surface of the steel plate 2, and any impurities or oil stains that may affect the welding quality should be removed; use a special cleaning agent and wiping tool to clean the surface of the steel plate 2 to ensure that the contact surface during welding is clean and flat.

[0019] S2. Weld all sides of the steel plate 2. The welding position is selected in the non-machining area of the steel plate 2. The weld seams 3 are arranged vertically, the width of each weld seam 3 is not less than 2 mm, and the distance between adjacent weld seams 3 is not greater than 20 mm. During the welding process, adopt appropriate welding processes and parameters to ensure that each layer of the steel plate 2 can be firmly welded together. An automatic welding device can be used to accurately control parameters such as welding current, voltage, and welding speed through a preset welding program to ensure the uniformity and stability of the welding quality. After welding, check the welded parts to ensure that there are no defects in the weld seams 3, such as porosity, slag inclusion, etc., and perform repair welding if necessary.

[0020] S3. Perform appropriate cooling treatment on the welded parts to avoid deformation of the steel plate 2 due to excessive temperature. Natural cooling or air cooling can be adopted to ensure that the steel plate 2 remains stable during the cooling process.

[0021] S4. Before performing subsequent cutting machining, check the stacking state of the steel plates 2 again to ensure that each side of each steel plate 2 is aligned without dislocation and there is no loosening between each layer of the steel plates 2; if the inspection is unqualified, return to S1.

[0022] Embodiment 1 Taking the cutting of a 100 mm × 100 mm blank steel plate 2 as an example,Figure 1 Before improvement, it was pressed by bolts on the fixture 1. Figure 2 To improve the pressing structure, after pressing the steel plate 2, several weld seams 3 are welded on the side of the steel plate 2 to ensure the fixation between the steel plates 2. Cut the center part and discard the edges.

[0023] Example 2 Select twenty steel plates 2 with a thickness of 2 mm, and the size is 100 mm × 200 mm. Use a laser alignment device to assist in stacking to ensure that the edge alignment accuracy of each steel plate 2 is within ±0.3 mm. Wipe the surface of the steel plate 2 with a lint-free cloth and a special cleaning agent to remove dust and oil on the surface.

[0024] Weld on the side of the steel plate 2. Use an automatic welding device, and the welding parameters are set as follows: welding current 200 A, welding voltage 25 V, welding speed 300 mm / min. After welding, use an ultrasonic flaw detector to detect the weld seam 3, and no defects such as pores and slag inclusions are found.

[0025] After welding, cool it by air cooling, and the cooling time is 10 minutes. After cooling, check the stacking state of the steel plate 2 again to confirm that the welding fixation effect is good and there is no loosening between the steel plates 2 of each layer. Then carry out cutting processing. During the processing, the stability of the steel plate 2 is good, and the processing accuracy meets the design requirements.

[0026] Example 3 Select thirty steel plates 2 with a thickness of 1 mm, and the size is 50 mm × 100 mm. Use a positioning caliper to assist in stacking to ensure that the edge alignment accuracy of each steel plate 2 is within ±0.2 mm. Wipe the surface of the steel plate 2 with alcohol and a lint-free cloth to remove dust and oil on the surface.

[0027] Weld on the side of the steel plate 2. Use a manual welding device, and the welding parameters are set as follows: welding current 100 A, welding voltage 20 V, welding speed 200 mm / min. After welding, use a magnifying glass to visually inspect the weld seam 3, and no defects such as pores and slag inclusions are found.

[0028] After welding, cool it by natural cooling, and the cooling time is 5 minutes. After cooling, check the stacking state of the steel plate 2 again to confirm that the welding fixation effect is good and there is no loosening between the steel plates 2 of each layer. Then carry out wire cutting processing. During the processing, the stability of the steel plate 2 is good, and the processing accuracy meets the design requirements.

[0029] In summary, the present invention can solve the problems that when small-batch production of wire cutting of thin steel plates, it is easy for the steel plates to loosen when clamped by fixtures, resulting in relative movement of the steel plates and causing the part dimensions to exceed the tolerance; at the same time, it can solve the problem that the fixture affects the fixation of the steel plate on the wire electrical discharge machining machine tool.

Claims

1. A method for fixing a thin steel plate during wire electrical discharge machining, characterized in that: It includes the following steps: S1. Stack a preset number of steel plates (2), ensuring that each side of each steel plate (2) is aligned without misalignment, and place them on the fixture (1) for fixation; S2. Weld all sides of the steel plates (2), select the welding positions in the non-machining areas of the steel plates (2), and set the weld seams (3) vertically; S3. Conduct appropriate cooling treatment on the welded parts; S4. Before subsequent cutting processing, check the stacking state of the steel plates (2) again to ensure that each side of each steel plate (2) is aligned without misalignment and there is no loosening between the layers of steel plates (2); if the inspection is unqualified, return to S1.

2. The method for fixing a thin steel plate by wire electrical discharge machining according to claim 1, wherein: In S1, use positioning tools to assist the operation to ensure that the edge error of each steel plate (2) is controlled within the threshold range.

3. The method for fixing a thin steel plate during wire electrical discharge machining according to claim 2, characterized in that: The positioning tools include positioning calipers and laser alignment devices.

4. The method for fixing the thin steel plate by wire electrical discharge machining according to claim 1, characterized in that: In S1, during the stacking process, use special cleaning agents and wiping tools to clean the surface of the steel plates (2) to ensure that the contact surfaces during welding are clean and flat.

5. The method for fixing a thin steel plate by wire electrical discharge machining according to claim 1, characterized in that: In S2, the width of each weld seam (3) is not less than 2 mm, and the distance between adjacent weld seams (3) is not more than 20 mm.

6. The method for fixing the thin steel plate by wire electrical discharge machining according to claim 1, characterized in that: In S2, after welding is completed, check the welded parts and perform repair welding if necessary.

7. The method for fixing the thin steel sheet by wire electrical discharge machining according to claim 1, characterized in that: In S3, the cooling treatment includes natural cooling and air cooling.

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