Method for solving upsetting and punching material pulling problems and ring forge piece forming method

Abstract

The invention relates to the technical field of forge piece forming, and discloses a method for solving the problems of upsetting, punching and material pulling and a ring forge piece forming method.The solving method comprises the steps that a bar heated to a first forging temperature is upset, an upset bar blank is obtained and comprises a first bar body and a second bar body, the first bar body is a cylinder, and the second bar body is a circular truncated cone; the diameter of the first rod body is the same as that of the second rod body; the upset bar blank heated to the second forging temperature is subjected to second bar body punching, then first bar body punching is conducted, an obtained annular blank comprises a first ring body and a second ring body, the first ring body is a circular ring body, the second ring body is a circular ring table, and the outer side face inclination of the second ring body is the same as that of the second bar body. By means of the method, material shortage caused by material pulling in the downward pressing process of the punch can be effectively compensated, the weight of the blank at the material pulling end after punching is guaranteed, corner collapse of the annular blank is prevented, and therefore the size of the follow-up ring forging forming production procedure is guaranteed, and the qualified rate of the size of the formed ring forging is increased.

Description

Technical Field

[0001] The present invention relates to the technical field of forging forming, and particularly relates to a method for solving the problems of upsetting and punching and pulling materials and a method for forming ring forgings. Background Art

[0002] During the forging process of ring forgings, opening holes in rod-shaped blanks is an essential process. Common hole-opening methods include punching with a punch, machining holes by turning, wire cutting holes, etc. Among them, the methods of machining holes by turning and wire cutting holes have disadvantages such as high cost, low efficiency, and high material consumption. Wire cutting holes require high equipment costs and relatively slow processing speeds. Therefore, the hole-opening method most commonly used is punching with a punch, which has the advantages of economy and speed.

[0003] When punching with a punch in the upsetting and punching processes, there is a problem of pulling materials. This is because there is friction between the punch and the blank. When the punch moves downward, the metal flow of the blank is hindered. Especially in the edge area where the punch contacts the blank, the metal is pulled, forming a pulling material phenomenon, resulting in uneven metal flow of the blank, causing metal accumulation or deformation around the hole after punching, and the metal at the edge of the hole will collapse inward, resulting in a large collapse angle of the blank after punching. Seriously, it will affect the forming size of the ring forgings in the subsequent horse-rack expanding or rolling processes.

[0004] To solve the problems of upsetting and punching and pulling materials, in the prior art, a conical punch or a stepped punch is used to make the metal flow more smoothly. However, such punches have high machining accuracy requirements and corresponding manufacturing costs will increase. For some ring forgings with special shapes or sizes, the optimized punch shape may need to be further adjusted and optimized, and the versatility is relatively poor. There is also the method of coating the surface of the punch with lubricating oil or using a lubricating coating to reduce the friction between the punch and the blank, thereby reducing the pulling material phenomenon. However, different materials and forging processes have different requirements for lubricants. Selecting a suitable lubricant requires a large number of experiments and verifications. At the same time, the lubricant may remain on the surface of the blank during the punching process and needs to be cleaned, increasing the production process and costs. Therefore, it is necessary to develop a new method for solving the problems of upsetting and punching and pulling materials. Summary of the Invention

[0005] The purpose of the present invention is to solve the problem that when punching with a punch in the existing upsetting and punching processes, there is pulling of materials, resulting in a large collapse angle of the blank and affecting the forming size of the subsequent production of ring forgings, and to provide a method for solving the problems of upsetting and punching and pulling materials and a method for forming ring forgings.

[0006] In the first aspect, the present invention provides a method for solving the problems of upsetting and punching and pulling materials, and the method includes: In the upsetting process, the bar heated to the first forging temperature is upset to obtain an upset bar blank. The upset bar blank includes a first bar body and a second bar body. The first bar body has a cylindrical structure, and the second bar body has a frustum structure. The diameter of the first bar body is the same as the diameter of the small end of the second bar body. In the punching process, the upset bar blank heated to the second forging temperature is punched. First, the second bar body is punched, and then the first bar body is punched to obtain an annular blank. The annular blank includes a first ring body and a second ring body. The first ring body has a toroidal structure, and the second ring body has a frustum of a toroid structure. The slope of the outer side surface of the second ring body is the same as the slope of the outer side surface of the second bar body. The design formula for the slope of the outer side surface of the second ring body is:

[0007] In the formula, α is the slope of the outer side surface of the second ring body. is the outer diameter of the first ring body, B is the inner diameter of the first ring body, and h is the height of the second ring body.

[0008] In the technical solution of the present invention, in the upsetting process, the heated bar is upset to change its shape. The obtained upset bar blank includes a first bar body and a second bar body which are coaxially and integrally arranged. The first bar body has a cylindrical structure, and the second bar body has a frustum structure. The diameter of the first bar body is the same as the diameter of the small end of the second bar body. The upset bar blank of the present invention is not a cylinder prepared by conventional upsetting, but a frustum structure of the second bar body is obtained by upsetting with the compensation method. The part of the second bar body that is more than the outer diameter of the first bar body is used as a reserved material shortage compensation area. In the subsequent punching process, the second bar body is punched first, and then the first bar body is punched. The obtained annular blank includes a first ring body and a second ring body which are coaxially and integrally arranged. The first bar body becomes the first ring body after punching, and the second bar body becomes the second ring body after punching. The slope of the outer side surface of the second ring body is the included angle between the side surface of the frustum of a toroid and the axis. The slope of the outer side surface of the second ring body is calculated by using the design formula. By controlling the slope of the outer side surface of the second ring body to be the same as the slope of the outer side surface of the second bar body, the reserved material shortage compensation area of the upset bar blank can effectively compensate for the material shortage caused by the pulling of the punch during the pressing process, ensure the weight of the blank at the pulling end after punching, prevent the annular blank from having a collapsed corner, thereby ensuring the dimensions of the subsequent ring forging forming production process and improving the qualified rate of the dimensions of the formed ring forging.

[0009] As a preferred embodiment of the present invention, the bar stock is heated to the first forging temperature and held. Since the materials of the bar stock are different, the forging temperatures used are also different. For bar stock made of superalloy materials, the first forging temperature is 950 - 1180 °C; for bar stock made of titanium alloy materials, the first forging temperature is 60 °C below the phase transition temperature of the titanium alloy material to 10 °C below the phase transition temperature; for bar stock made of steel materials, the first forging temperature is 850 - 1180 °C; for bar stock made of aluminum alloy materials, the first forging temperature is 400 - 480 °C; for bar stock made of copper alloy materials, the first forging temperature is 600 - 950 °C; for bar stock made of magnesium alloy materials, the first forging temperature is 300 - 480 °C.

[0010] As a preferred embodiment of the present invention, the upset bar blank is heated to the second forging temperature and held. Since the materials are different, the temperatures used are also different. For superalloy materials, the second forging temperature is 950 - 1180 °C; for titanium alloy materials, the second forging temperature is 60 °C below the phase transition temperature of the titanium alloy material to 10 °C below the phase transition temperature; for steel materials, the second forging temperature is 850 - 1180 °C; for aluminum alloy materials, the second forging temperature is 400 - 480 °C; for copper alloy materials, the second forging temperature is 600 - 950 °C; for magnesium alloy materials, the second forging temperature is 300 - 480 °C. In the technical solution of the present invention, the first forging temperature and the second forging temperature can be the same or different. During the upsetting and stamping processes, the blank is heated to the corresponding forging temperature. An appropriate forging temperature can improve the plasticity of the metal and reduce the deformation resistance, making it easier to flow. If the temperature is too high, the metal may experience overheating or burning, resulting in a decline in metal properties; if the temperature is too low, the plasticity of the metal is insufficient, and it is difficult to upset or punch smoothly. Therefore, the first forging temperature or the second forging temperature is precisely controlled according to the specific material and blank size.

[0011] As a preferred embodiment of the present invention, during the punching process, the diameter of the punch is the same as the inner diameter of the first ring body. The conditions that the punch diameter design needs to meet are:

[0012] where is the inner diameter of the first ring body, that is, the punch diameter, and δ is the stamping forging constant, which is determined according to materials and forging process experience.

[0013] Furthermore, the stamping forging constant is selected within the range of 2.5 - 3.2.

[0014] As a preferred embodiment of the present invention, the design formula for the height of the second ring body is

[0015] Wherein is the height of the ring blank, is the blank holding constant, which is determined according to material and forging process experience.

[0016] Furthermore, the blank holding constant is selected within the range of 0.65 - 0.75.

[0017] As a preferred embodiment of the present invention, the downward pressing speed of the punch during stamping is 10 - 80 mm / s. In the above technical solution, the downward pressing speed of the punch will affect the stability of the forming size. If the punching speed is too fast, it will cause uneven metal flow, increasing the risk of blank holding and corner collapse; if the punching speed is too slow, it will reduce production efficiency. Through experiments and simulation analysis, the optimal downward pressing speed of the punch is determined to be 10 - 80 mm / s, making the metal flow more stable.

[0018] In a second aspect, the present invention provides a method for forming a ring forging, comprising the following steps: S1. Cutting a bar according to the finished product parameter requirements; S2. Upsetting and punching the bar by using the above method for solving the problems of upsetting and punching blank holding to obtain a ring blank; S3. Expanding and rolling the ring blank to obtain a ring forging.

[0019] In the above technical solution, the bar is upset and punched by the compensation method. The reserved material compensation area for upsetting the bar blank can effectively compensate for the material shortage caused by blank holding during the downward pressing process of the punch, ensuring the weight of the blank at the blank holding end after punching, preventing corner collapse of the ring blank, ensuring the size of the formed ring forging, and improving the qualified rate of the size of the formed ring forging.

[0020] In a third aspect, the present invention provides a ring forging, which is manufactured by using the above method for solving the problems of upsetting and punching blank holding.

[0021] Compared with the prior art, the beneficial effects of the present invention: 1. The present invention provides a method for solving the problems of upsetting and punching and pulling materials. In the upsetting process, the heated bar stock is upset to change its shape. The upset bar blank obtained includes a first bar body and a second bar body arranged coaxially and integrally. The first bar body is a cylindrical structure, and the second bar body is a frustum of a cone structure. The diameter of the first bar body is the same as the diameter of the small end of the second bar body. Instead of the conventional cylindrical shape prepared by upsetting, the second bar body is a frustum of a cone structure by upsetting with the compensation method. The part of the second bar body that is more than the outer diameter of the first bar body is used as a reserved material shortage compensation area. In the subsequent punching process, the second bar body is punched first, and then the first bar body is punched. The obtained annular blank includes a first ring body and a second ring body arranged coaxially and integrally. The slope of the outer side of the second ring body is the included angle between the side surface of the circular frustum and the axis. The slope of the outer side of the second ring body is calculated by using a design formula. By controlling the slope of the outer side of the second ring body to be the same as the slope of the outer side of the second bar body, the reserved material shortage compensation area of the upset bar blank can effectively compensate for the material shortage caused by pulling during the downward pressing of the punch, ensure the weight of the blank at the pulling end after punching, prevent the annular blank from having a collapsed corner, and thus ensure the dimensions of the subsequent ring forging forming production process and improve the qualified rate of the dimensions of the formed ring forging.

[0022] 2. The present invention solves the common problems in the blank making process of upsetting and punching for ring forgings of metal materials. This method can be widely used in various metal materials such as superalloys, steels, aluminum alloys, titanium alloys, copper alloys, and magnesium alloys. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a cross-sectional view of the bar stock in Example 2; Figure 2 It is a schematic diagram of the upsetting process in Example 2; Figure 3 It is a cross-sectional view of the upset bar blank in Example 2; Figure 4 It is a schematic diagram of the punching process in Example 2; Figure 5 It is a cross-sectional view of the annular blank in Example 2; Figure 6 It is a cross-sectional view of the ring forging in Example 3; Reference signs in the figures: 1 - bar stock, 2 - die set, 3 - backing plate, 4 - upset bar blank, 41 - first bar body, 42 - second bar body, 5 - annular blank, 51 - first ring body, 52 - second ring body, 6 - punch, 7 - ring forging. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] The present invention will be further described in detail below in conjunction with specific embodiments. However, this should not be construed as limiting the scope of the above-mentioned subject matter of the present invention to the following embodiments. All technologies implemented based on the content of the present invention belong to the scope of the present invention.

[0025] In the description of the specific embodiments of the present invention, without special explanation, the expression terms indicating the orientation or positional relationship such as "upper", "lower", "left", "right", "center", "inner", "outer", etc. are all based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship when the invention product / device / device is usually used. These terms of orientation or positional relationship are only for the convenience of describing the solution of the present invention or simplifying the description in the specific embodiment, so as to facilitate technicians to quickly understand the solution, rather than indicating or implying that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, it should not be construed as a limitation to the present invention.

[0026] In addition, if terms such as "horizontal", "vertical", "hanging", "parallel" appear, it does not mean that the corresponding device / component / element is required to be absolutely horizontal or vertical or hanging or parallel, but can be slightly inclined or have a deviation. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined. Or, it can be simply understood that the corresponding device / component / element is arranged in the directions of "horizontal", "vertical", "hanging", "parallel", etc., and can have an error / deviation of ±10% relative to the corresponding direction setting, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, more preferably within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still play its role in the solution of the present invention.

[0027] In addition, the expressions such as "first", "second", "third", etc. in the terms are only used to distinguish the description of the same or similar components, and should not be construed as emphasizing or implying the relative importance of specific components.

[0028] In addition, in the description of the embodiments of the present invention, "several", "multiple", "a number of" represent at least 2. It can be any situation such as 2, 3, 4, 5, 6, 7, 8, 9, etc., or even more than 9.

[0029] In addition, in the description of the technical solution of the present invention, unless otherwise clearly specified / defined / restricted, when the terms "set", "installed", "connected", "linked", "provided with", "laid", "arranged" appear, they should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection. It can be connection means commonly used in the art such as welding, riveting, bolting, and threaded connection. Such a connection can be a mechanical connection, an electrical connection, or a communication connection; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two components.

[0030] Embodiment 1 This embodiment provides a method for solving the problems of upsetting and punching and pulling materials. The method includes: In the upsetting process, the bar heated to the first forging temperature is upset to obtain an upset bar blank. The upset bar blank includes a first bar body and a second bar body. The first bar body is a cylindrical structure, and the second bar body is a frustum structure. The diameter of the first bar body is the same as the diameter of the small end of the second bar body. The bar is heated to the first forging temperature and held. Since the materials of the bar are different, the forging temperatures used are also different. For bars made of superalloy materials, the first forging temperature is 950 - 1180 °C. Superalloy materials include, but are not limited to, one of Waspaloy, GH4169, IN718, GH3536, IN783, IN625, GH4698. For different types of superalloy materials, the first forging temperature is different, and the forging temperature range is determined according to the specific material grade; for bars made of titanium alloy materials, the first forging temperature is 60 °C below the phase transition temperature of the titanium alloy material to 10 °C below the phase transition temperature. Titanium alloy materials include, but are not limited to, one of Ti6242, Ti64, TC11, TC4, TA12A, TA7, TA15, etc. For different types of titanium alloy materials, the first forging temperature will be adjusted according to the phase transition temperature of the specific material grade to ensure that the plasticity of the titanium alloy is relatively high and the deformation resistance is relatively low at the forging temperature; for bars made of steel materials, the first forging temperature is 850 - 1180 °C; for bars made of aluminum alloy materials, the first forging temperature is 400 - 480 °C; for bars made of copper alloy materials, the first forging temperature is 600 - 950 °C; for bars made of magnesium alloy materials, the first forging temperature is 300 - 480 °C. During the upsetting and stamping processes, the blank is heated to the corresponding forging temperature. The appropriate forging temperature can improve the plasticity of the metal and reduce the deformation resistance, making it easier to flow.

[0031] In the punching process, the upset bar blank heated to the second forging temperature is punched. First, the second bar body is punched, and then the first bar body is punched to obtain an annular blank. The annular blank includes a first ring body and a second ring body. The first ring body is a circular ring structure, and the second ring body is a frustum of a circular ring structure.

[0032] The upsetting billet is heated to the second forging temperature. Different materials have different applicable temperatures. For superalloy materials, the second forging temperature is 950 - 1180 °C; for titanium alloy materials, the second forging temperature is 60 °C below the phase transition temperature of the titanium alloy material to 10 °C below the phase transition temperature; for steel materials, the second forging temperature is 850 - 1180 °C; for aluminum alloy materials, the second forging temperature is 400 - 480 °C; for copper alloy materials, the second forging temperature is 600 - 950 °C; for magnesium alloy materials, the second forging temperature is 300 - 480 °C. The selection of the first forging temperature and the second forging temperature can be the same or different, without specific limitations.

[0033] The slope of the outer side of the second ring body is the same as that of the outer side of the second rod body. The slope of the outer side refers to the inclination degree of the side surface of the frustum of a circular cone, which is defined by an angle. The slope of the outer side of the second ring body is the angle between the side surface of the frustum of a circular cone and the axis of the frustum of a circular cone. The larger the angle, the greater the slope; the smaller the angle, the smaller the slope. According to the length relationship, the relational formula between the length and the angle is derived, and then the angle is obtained through the arctangent function. Thus, the design formula for the slope of the outer side of the second ring body is:

[0034] In the formula, α is the slope of the outer side of the second ring body, with the unit of °; is the outer diameter of the first ring body, with the unit of mm; B is the inner diameter of the first ring body, with the unit of mm; h is the height of the second ring body, with the unit of mm. The punch diameter is the same as the inner diameter of the first ring body. The conditions that the punch diameter design needs to meet are:

[0035] In the formula, δ is the stamping forging constant, which is determined according to materials and forging process experience and is selected within the range of 2.5 - 3.2.

[0036] The design formula for the height of the second ring body is:

[0037] In the formula is the height of the annular blank, with the unit of mm; is the material drawing constant, which is determined according to materials and forging process experience and is selected within the range of 0.65 - 0.75.

[0038] Furthermore, during the stamping process, the downward pressing speed of the punch is 10 - 80 mm / s. The downward pressing speed of the punch will affect the stability of the forming size. When the downward pressing speed of the punch is 10 - 80 mm / s, the metal flow is more stable.

[0039] Example 2 This embodiment provides a method for solving the problems of upsetting and punching and pulling materials. The method of Embodiment 1 is adopted, and the bar stock 1 used is as follows Figure 1 shown. The bar stock 1 is made of the superalloy GH4169, with a diameter of 250 mm and a height of 325 mm.

[0040] In the upsetting process, the bar stock 1 is heated to the first forging temperature of 1000 - 1080 °C and held for a period of time. After heating, the bar stock 1 is upset in the die set 2. The bottom of the die set 2 is the backing plate 3, and the profile of the die set matches the formed upset bar blank 4, as Figure 2 shown, to obtain the upset bar blank 4. The upset bar blank 4 includes a first bar body 41 and a second bar body 42. The first bar body 41 and the second bar body 42 are coaxially arranged integral structures, as Figure 3 shown. The first bar body 41 is a cylindrical structure, and the second bar body 42 is a frustum structure. The diameter of the first bar body 41 is the same as the diameter of the small end of the second bar body 42. After upsetting, the height of the upset bar blank 4 is 215 mm, the diameter of the small end is 301 mm, and the diameter of the large end is 313.4 mm.

[0041] In the punching process, the upset bar blank 4 is heated to the second forging temperature of 1000 - 1080 °C and held for a period of time. The punch 6 is first used to punch the second bar body 42, as Figure 4 shown. After turning it over, the first bar body 41 is punched to obtain the ring blank 5. The ring blank 5 includes a first ring body 51 and a second ring body 52. The first ring body 51 and the second ring body 52 are coaxially arranged integral structures, as Figure 5 shown. After punching, the first bar body 41 becomes the first ring body 51, and the second bar body 42 becomes the second ring body 52. The first ring body is a circular ring structure, and the second ring body is a circular frustum structure. The inner diameter of the first ring body is the same as the inner diameter of the small end of the second ring body. After punching, the height of the ring blank 5 is 215 mm, the inner diameter is 110 mm, the outer diameter of the small end is 320 mm, the inner diameter of the large end is 140 mm, the outer diameter of the large end is 332.4 mm, and the slope of the outer side of the second ring body is 2.21°. The inner diameter of the large end is the dimension at the upper end face of the second ring body. The ring forging prepared by subjecting the prepared ring blank to horse - frame hole expanding, rectangular rolling, and final rolling does not have the defect of corner collapse.

[0042] Embodiment 3 In a second aspect, this embodiment provides a ring forging. The forming method of the ring forging includes the following steps: S1. Cut the bar stock according to the requirements of the finished product parameters; S2. Use the method for solving the problems of upsetting and punching and pulling materials in Embodiment 2 to upset and punch the bar stock to obtain the ring blank; S3. Perform cage expanding, rectangular rolling, and finish rolling on the ring blank to obtain the ring forging 7, as Figure 6 shown. Inspect the appearance and dimensions of the obtained ring forging. The dimensions are to measure the thickness, inner diameter, and outer diameter at different heights of the ring forging. The different heights are based on the lower end face. For example, the 1 / 4 height position is the position at 1 / 4 of the height of the ring forging from the lower end face. No corner collapse defects or other defects are found in the appearance inspection of the ring forging. The dimensional results are shown in Table 1. It can be seen from the data that the dimensions of the ring forging fluctuate within a certain range, meeting the process design requirements.

[0043] Table 1 Dimensional inspection results of the ring forging in Example 3

[0044] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for solving the problems of upsetting and punching and pulling materials, characterized in that, The method includes: In the upsetting process, the bar heated to the first forging temperature is upset to obtain an upset bar blank. The upset bar blank includes a first bar body and a second bar body. The first bar body is a cylindrical structure, and the second bar body is a frustum structure. The diameter of the first bar body is the same as the diameter of the small end of the second bar body. In the punching process, the upset bar blank heated to the second forging temperature is punched. First, the second bar body is punched, and then the first bar body is punched to obtain an annular blank. The annular blank includes a first ring body and a second ring body. The first ring body is a circular ring structure, and the second ring body is a frustum of a circular ring structure. The slope of the outer side of the second ring body is the same as the slope of the outer side of the second bar body. The design formula for the slope of the outer side of the second ring body is: where α is the slope of the outer side surface of the second ring body, is the outer diameter of the first ring body, B is the inner diameter of the first ring body, and h is the height of the second ring body.

2. A method for solving the problems of upsetting, punching and pulling materials according to claim 1, characterized in that The bar is heated to the first forging temperature and held. For bars made of superalloy materials, the first forging temperature is 950 - 1180 °C; for bars made of titanium alloy materials, the first forging temperature is 60 °C below the phase transition temperature of the titanium alloy material to 10 °C below the phase transition temperature; for bars made of steel materials, the first forging temperature is 850 - 1180 °C; for bars made of aluminum alloy materials, the first forging temperature is 400 - 480 °C; for bars made of copper alloy materials, the first forging temperature is 600 - 950 °C; for bars made of magnesium alloy materials, the first forging temperature is 300 - 480 °C.

3. A method for solving the problems of upsetting, punching and pulling materials according to claim 1, characterized in that, The upset bar blank is heated to the second forging temperature and held. For superalloy materials, the second forging temperature is 950 - 1180 °C; for titanium alloy materials, the second forging temperature is 60 °C below the phase transition temperature of the titanium alloy material to 10 °C below the phase transition temperature; for steel materials, the second forging temperature is 850 - 1180 °C; for aluminum alloy materials, the second forging temperature is 400 - 480 °C; for copper alloy materials, the second forging temperature is 600 - 950 °C; for magnesium alloy materials, the second forging temperature is 300 - 480 °C.

4. A method for solving the problems of upsetting, punching and material drawing according to claim 1, characterized in that During the punching process, the diameter of the punch is the same as the inner diameter of the first ring body. The conditions that the punch diameter design needs to meet are: In the formula, δ is the stamping forging constant, which is determined according to materials and forging process experience.

5. A method for solving the problems of upsetting, punching and material drawing according to claim 4, characterized in that, The stamping forging constant is selected within the range of 2.5 - 3.

2.

6. A method for solving the problems of upsetting and punching and pulling materials according to claim 1, characterized in that The design formula for the height of the second ring body is: In the formula is the height of the ring blank, is the blank holding constant, which is determined according to material and forging process experience.

7. A method for solving the problems of upsetting, punching and pulling materials according to claim 6, characterized in that, The draw constant is selected within the range of 0.65 - 0.

75.

8. A method for solving the problems of upsetting, punching and material drawing according to any one of claims 1-7, characterized in that, The downward pressing speed of the punch during stamping is 10 - 80 mm / s.

9. A method for forming a ring forging, characterized in that, It includes the following steps: S1. Cut the bar according to the requirements of the finished product parameters to obtain the bar. S2. Use the method for solving the problems of upsetting, punching, and drawing of the bar described in any one of claims 1 - 8 to upset and punch the bar to obtain the annular blank. S3. Expand and roll the annular blank to obtain a ring forging.

10. A ring forging, characterized in that, The ring forging is manufactured by using the method for forming a ring forging described in claim 9.

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