Gate molybdenum ring processing method for IGCT device

Abstract

The invention relates to the technical field of gate molybdenum ring processing, and discloses a gate molybdenum ring processing method for an IGCT device, which comprises the following steps: sequentially carrying out primary thinning, turning, secondary thinning, excircle chamfer manufacturing, inner hole manufacturing through laser cutting, inner hole manufacturing through linear cutting, inner hole manufacturing through boring, inner hole manufacturing through finish machining and third thinning on a molybdenum ring; in actual use, the initial hole diameter of the inner hole of the molybdenum ring is manufactured in a laser cutting mode, compared with a mode of manufacturing the molybdenum ring through a punching process, due to laser cutting machining, the molybdenum ring is good in overall flatness, an additional mold is not needed, in addition, the method is simple, convenient, high in precision and high in machining efficiency, and the large-scale production requirement can be met.

Description

Technical Field

[0001] The present invention relates to the technical field of gate molybdenum ring processing, and specifically relates to a method for processing a gate molybdenum ring for an IGCT device. Background Art

[0002] IGCT (Integrated Gate Commutated Thyristor), a switching device that combines the advantages of IGBT (Insulated Gate Bipolar Transistor) and GTO (Gate Turn-Off Thyristor), has a capacity equivalent to that of GTO, but its switching speed is ten times faster than that of GTO; moreover, it has advantages such as large current, high blocking voltage, high switching frequency, high reliability, compact structure, low conduction loss, low cost, and high yield, and is widely used in various fields.

[0003] In order to quickly dissipate the heat generated during the operation of IGCT, the gate molybdenum ring is adopted as the core heat dissipation device of IGCT due to its excellent heat dissipation characteristics and high throughput. Due to the unique form of the gate molybdenum ring, its diameter is mostly between 40 mm and 120 mm, the wall thickness is only between 1 mm and 3 mm, the thickness is mostly between 2 mm and 4 mm, and the overall flatness requirement is only 5 μm. Therefore, the processing difficulty of its overall flatness is extremely high.

[0004] When processing existing molybdenum alloy molybdenum rings, punching is often the main method. However, this processing method has problems such as large punching deformation and extremely poor flatness, and cannot meet the overall flatness requirements of the molybdenum ring. Summary of the Invention

[0005] In view of the deficiencies of the background art, the present invention provides a method for processing a gate molybdenum ring for an IGCT device, and the technical problem to be solved is the problems of large deformation and poor flatness when processing the molybdenum ring for IGCT heat dissipation by punching.

[0006] To solve the above technical problems, the present invention provides the following technical solutions: A method for processing a gate molybdenum ring for an IGCT device, including the following steps:

[0007] S1: Thinning the thickness of the molybdenum ring once to reduce the thickness of the molybdenum ring to the first thickness;

[0008] S2: Processing the outer diameter of the molybdenum ring by turning technology to process the diameter of the molybdenum ring to the first diameter;

[0009] S3: Thinning the thickness of the molybdenum ring twice to reduce the thickness of the molybdenum ring to the second thickness;

[0010] S4: Making an outer circular chamfer on the outer wall surface of the molybdenum ring;

[0011] S5: Processing the molybdenum ring by laser cutting technology to make an inner hole of the molybdenum ring, and the aperture of the inner hole is the first aperture;

[0012] S6: Continue to machine the inner hole of the molybdenum ring through wire cutting process, and machine the aperture of the inner hole of the molybdenum ring to the second aperture;

[0013] S7: Continue to machine the inner hole of the molybdenum ring through boring process, and machine the aperture of the inner hole of the molybdenum ring to the third aperture;

[0014] S8: Finish machining the inner hole of the molybdenum ring, and machine the aperture of the molybdenum ring to the fourth aperture, and the first aperture, the second aperture, the third aperture and the fourth aperture increase in sequence;

[0015] S9: Reduce the thickness of the molybdenum ring three times, and reduce the thickness of the molybdenum ring to the third thickness, and the first thickness, the second thickness and the third thickness decrease in sequence.

[0016] In a certain embodiment, the present invention further includes step S10, and step S10 is as follows:

[0017] S10: Clean the molybdenum ring.

[0018] In a certain embodiment, in step S1, the thickness of the molybdenum ring is reduced once through rough and finish grinding process.

[0019] In a certain embodiment, in the turning process of step S2, a formed alloy tool is used to machine the outer diameter of the molybdenum ring.

[0020] In a certain embodiment, in step S4, an anti-vibration tool sleeve and a formed alloy tool are used to machine the molybdenum ring to make an outer circle chamfer.

[0021] In a certain embodiment, in the boring process of step S7, a cemented carbide tool is used to machine the inner hole of the molybdenum ring.

[0022] In a certain embodiment, in step S8, the inner hole of the molybdenum ring is finish machined through a cemented carbide tool sleeve and a cemented carbide tool.

[0023] In a certain embodiment, in step S9, the molybdenum ring is ground with 2000-mesh fine abrasive sand, and the thickness of the molybdenum ring is reduced to the third thickness.

[0024] In a certain embodiment, the value of the first thickness is between 3.82 mm and 3.85 mm, the value of the second thickness is between 3.70 mm and 3.73 mm, and the value of the third thickness is between 3.66 mm and 3.67 mm.

[0025] In some embodiments, the value of the first aperture is between 43.05 mm and 43.06 mm; the value of the second aperture is between 43.07 mm and 43.09 mm; the value of the third aperture is between 43.70 mm and 43.80 mm; the value of the fourth aperture is between 44.0 mm and 44.10 mm.

[0026] The beneficial effects of the present invention compared with the prior art are as follows: First, the initial aperture of the inner hole of the molybdenum ring is made by laser cutting. Compared with making the molybdenum ring using a punching process, since it is laser cutting, the overall flatness of the molybdenum ring is good, and no additional molds are required. In addition, it is simple, convenient, has high precision and fast processing efficiency, and can meet the needs of large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a flow chart of the present invention in the embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] Now, the present invention will be further described in detail with reference to the accompanying drawings. These drawings are all simplified schematic diagrams, only illustrating the basic structure of the present invention in a schematic manner, so they only show the components related to the present invention.

[0029] As Figure 1 shown, a method for processing a gate molybdenum ring for an IGCT device includes the following steps:

[0030] S1: Thinning the thickness of the molybdenum ring once to reduce the thickness of the molybdenum ring to the first thickness.

[0031] Specifically, in step S1, the thickness of the molybdenum ring is thinned once through a rough and fine grinding process; the rough and fine grinding process is as follows: According to the processed molybdenum ring specification size, a planetary gear and a 100-mesh rough and fine grinding wheel are used in combination to reduce the thickness of the molybdenum ring to the first thickness; in addition, the value of the first thickness is determined according to the actual required molybdenum ring size. Exemplarily, taking the molybdenum ring with an outer diameter of 47.2 mm, an inner diameter of 44 mm, and a thickness of 3.6 mm as an example, the value of the first thickness is between 3.82 mm and 3.85 mm.

[0032] S2: Processing the outer diameter of the molybdenum ring through a turning process to process the diameter of the molybdenum ring to the first diameter.

[0033] Specifically, in the turning process of step S2, a formed alloy tool is used to machine the outer diameter of the molybdenum ring, so as to ensure that the outer diameter dimensional tolerance of the molybdenum ring is within the range of 0.03 mm to 0.05 mm, and at the same time, the coaxiality of the molybdenum ring can be controlled within 0.03 mm to 0.04 mm; Exemplarily, taking the molybdenum ring with an outer diameter of 47.2 mm, an inner diameter of 44 mm, and a thickness of 3.6 mm as an example, the value of the first diameter is between 47.25 mm and 47.28 mm.

[0034] S3: Secondarily thin the thickness of the molybdenum ring to a second thickness.

[0035] Specifically, in step S3, the molybdenum ring is secondarily thinned by a rough grinding process. Specifically, 600-mesh abrasive sand and water are selected and used in conjunction with grinding equipment to machine the thickness of the molybdenum ring, and the thickness of the molybdenum ring is thinned to the second thickness; In actual production, through step S3, the thickness of the molybdenum ring can be preliminarily shaped. Among them, a 13B precision grinding equipment can be used to machine the molybdenum ring. During processing, it is necessary to ensure that the thickness dimensional tolerance is between 0.02 mm and 0.03 mm, and the flatness dimension of the molybdenum ring is controlled between 0.005 mm and 0.006 mm; Exemplarily, taking the molybdenum ring with an outer diameter of 47.2 mm, an inner diameter of 44 mm, and a thickness of 3.6 mm as an example, the value of the second thickness is between 3.70 mm and 3.73 mm.

[0036] S4: Make an outer circular chamfer on the outer wall surface of the molybdenum ring.

[0037] Specifically, in step S4, an anti-vibration tool sleeve and a formed alloy tool are used to machine the molybdenum ring to make an outer circular chamfer. During the manufacturing process, it is necessary to ensure that the chamfer dimension tolerance is controlled between 0.05 mm and 0.06 mm, and the concentricity dimension is controlled between 0.03 mm and 0.04 mm.

[0038] S5: Machine the molybdenum ring through a laser cutting process to make an inner hole in the molybdenum ring, and the aperture of the inner hole is the first aperture.

[0039] Specifically, a high-precision laser cutting equipment can be used to machine the inner hole of the molybdenum ring, so as to ensure the inner hole deformation amount and guarantee the accuracy for the following processing procedures; During the laser cutting process, the power of the laser can be set to 3KW. In addition, as the thickness of the molybdenum ring increases, the power of the laser becomes larger; Exemplarily, taking the molybdenum ring with an outer diameter of 47.2 mm, an inner diameter of 44 mm, and a thickness of 3.6 mm as an example, the value of the first aperture is between 43.05 mm and 43.06 mm.

[0040] S6: Continue to machine the inner hole of the molybdenum ring through a wire cutting process to machine the aperture of the inner hole of the molybdenum ring to the second aperture.

[0041] In actual production, the power amplifier of the wire cutting equipment can be set to 4, the pulse width of the wire cutting equipment can be set to 8 ms, and the pulse interval of the wire cutting equipment can be set to 8 ms.

[0042] In actual use, the value of the second aperture is determined according to the size of the molybdenum ring to be machined. Exemplarily, taking the molybdenum ring with an outer diameter of 47.2 mm, an inner diameter of 44 mm, and a thickness of 3.6 mm as an example, the value of the second aperture is between 43.07 mm and 43.09 mm.

[0043] S7: Continuously machine the inner hole of the molybdenum ring through the boring process to machine the aperture of the inner hole of the molybdenum ring to the third aperture.

[0044] Specifically, in the boring process of step S7, a cemented carbide tool is used to machine the inner hole of the molybdenum ring, so as to ensure that the dimensional tolerance is between 0.02 mm and 0.03 mm and the concentricity dimension is controlled between 0.03 mm and 0.04 mm when the aperture of the molybdenum ring is machined to the third aperture; Exemplarily, taking the molybdenum ring with an outer diameter of 47.2 mm, an inner diameter of 44 mm, and a thickness of 3.6 mm as an example, the value of the third aperture is between 43.70 mm and 43.80 mm.

[0045] S8: Finish machine the inner hole of the molybdenum ring to machine the aperture of the molybdenum ring to the fourth aperture, and the first aperture, the second aperture, the third aperture, and the fourth aperture increase in sequence.

[0046] Specifically, in step S8, the inner hole of the molybdenum ring is finish machined through a cemented carbide tool sleeve and a cemented carbide tool, so as to ensure that the aperture size error is controlled between 0.01 mm and 0.02 mm and the concentricity dimension is controlled between 0.01 mm and 0.02 mm when the aperture of the molybdenum ring is machined to the fourth aperture. At the same time, the tool vibration during machining is also reduced to avoid tool marks on the inner hole of the molybdenum ring. Exemplarily, taking the molybdenum ring with an outer diameter of 47.2 mm, an inner diameter of 44 mm, and a thickness of 3.6 mm as an example, the value of the fourth aperture is between 44.0 mm and 44.10 mm.

[0047] S9: Thinning the thickness of the molybdenum ring three times to thin the thickness of the molybdenum ring to the third thickness, and the first thickness, the second thickness, and the third thickness decrease in sequence.

[0048] Specifically, in step S9, the molybdenum ring is ground with 2000-mesh fine abrasive sand to thin the thickness of the molybdenum ring to the third thickness. Exemplarily, taking the molybdenum ring with an outer diameter of 47.2 mm, an inner diameter of 44 mm, and a thickness of 3.6 mm as an example, the value of the third thickness is between 3.66 mm and 3.67 mm.

[0049] In this embodiment, the present invention further includes step S10, and step S10 is as follows:

[0050] S10: Clean the molybdenum ring.

[0051] Specifically, clean the molybdenum ring with a mixed solution of nitric acid and sulfuric acid, where the ratio of nitric acid to sulfuric acid is 5:1, so as to clean the abrasive sand and the oxide layer of the metal flow layer on the molybdenum ring.

[0052] In summary, the present invention uses laser cutting to produce the initial aperture of the inner hole of the molybdenum ring. Compared with the production of molybdenum rings using the punching process, since it is a cutting process, the overall flatness of the molybdenum ring is good, and no additional molds are required. In addition, it is simple, convenient, has high precision and fast processing efficiency, and can meet the needs of mass production.

[0053] Based on the inspiration of the present invention, through the above description, relevant staff can completely make various changes and modifications without departing from the technical idea of the present invention. The technical scope of the present invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A method for processing the gate molybdenum ring for an IGCT device, characterized in that, It includes the following steps: S1: Thinning the thickness of the molybdenum ring for the first time to reduce the thickness of the molybdenum ring to the first thickness; S2: Processing the outer diameter of the molybdenum ring through a turning process to process the diameter of the molybdenum ring to the first diameter; S3: Thinning the thickness of the molybdenum ring for the second time to reduce the thickness of the molybdenum ring to the second thickness; S4: Making an external chamfer on the outer wall surface of the molybdenum ring; S5: Processing the molybdenum ring through a laser cutting process to make an inner hole in the molybdenum ring, and the aperture of the inner hole is the first aperture; S6: Continuing to process the inner hole of the molybdenum ring through a wire cutting process to process the aperture of the inner hole of the molybdenum ring to the second aperture; S7: Continuing to process the inner hole of the molybdenum ring through a boring process to process the aperture of the inner hole of the molybdenum ring to the third aperture; S8: Finishing the inner hole of the molybdenum ring to process the aperture of the molybdenum ring to the fourth aperture, and the first aperture, the second aperture, the third aperture, and the fourth aperture increase in sequence; S9: Thinning the thickness of the molybdenum ring for the third time to reduce the thickness of the molybdenum ring to the third thickness, and the first thickness, the second thickness, and the third thickness decrease in sequence.

2. The gate molybdenum ring processing method for an IGCT device according to claim 1, wherein It also includes step S10, and step S10 is as follows: S10: Cleaning the molybdenum ring.

3. The gate molybdenum ring processing method for an IGCT device according to claim 1, characterized in that In step S1, the thickness of the molybdenum ring is thinned for the first time through a rough and fine grinding process.

4. A method for processing a gate molybdenum ring for an IGCT device according to claim 1, characterized in that, In the turning process of step S2, a formed alloy tool is used to process the outer diameter of the molybdenum ring.

5. A method for machining a gate molybdenum ring for an IGCT device according to claim 1, characterized in that, In step S4, an anti-vibration tool sleeve and a formed alloy tool are used to process the molybdenum ring to make an external chamfer.

6. The gate molybdenum ring processing method for an IGCT device according to claim 1, characterized in that In the boring process of step S7, a cemented carbide tool is used to process the inner hole of the molybdenum ring.

7. A method for machining a gate molybdenum ring for an IGCT device according to claim 1, characterized in that, In step S8, the inner hole of the molybdenum ring is finely processed through a cemented carbide tool sleeve and a cemented carbide tool.

8. A method for processing a gate molybdenum ring for an IGCT device according to claim 1, characterized in that, In step S9, the molybdenum ring is ground with 2000-mesh fine abrasive to reduce the thickness of the molybdenum ring to the third thickness.

9. The gate molybdenum ring processing method for an IGCT device according to claim 1, characterized in that, The value of the first thickness is between 3.82 mm and 3.85 mm, the value of the second thickness is between 3.70 mm and 3.73 mm, and the value of the third thickness is between 3.66 mm and 3.67 mm.

10. A method for processing a gate molybdenum ring for an IGCT device according to claim 1, characterized in that, The value of the first aperture is between 43.05 mm and 43.06 mm; the value of the second aperture is between 43.07 mm and 43.09 mm; the value of the third aperture is between 43.70 mm and 43.80 mm; the value of the fourth aperture is between 44.0 mm and 44.10 mm.

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