A method for preparing a large taper special-shaped ring disc component by roll forming and composite forming process

Abstract

A kind of big taper special-shaped ring disc component spin rolling composite forming process blank making method, by the initial blank of determined blank size, the initial blank is rolled into the intermediate blank of slightly smaller than the inner diameter, slightly higher than the inner circle and slightly larger than the outer diameter of final forming special-shaped ring disc piece by ring rolling, and finally the intermediate blank is plastically deformed by ring rolling to obtain the required big taper special-shaped spin rolling blank.The invention implements dynamic and continuous local rolling effect on ring piece by roller, makes material deformation concentrate in transient contact area, and significantly reduces overall rolling torque while realizing precise expansion of ring piece diameter by using metal flow characteristics.Firstly, this process method not only maintains the rigid support effect of non-contact area of ring blank, but also reduces forming resistance by 30%-50% compared with traditional overall deformation process.Secondly, it greatly reduces the cutting amount, increases the material utilization rate from 30% to 70%, thereby reducing the production cost by 20%-25%, finally, this process method can effectively solve the problems of low material utilization rate, high cost and difficult to guarantee performance in the production process of big taper special-shaped ring disc component.

Description

Technical Field

[0001] This invention belongs to the field of plastic processing technology, specifically relating to a method for preparing blanks using a rotary rolling composite forming process for large-tapered irregular-shaped ring-disc components. Background Technology

[0002] Irregularly shaped ring-disc components refer to metallic components with a rotating structure, including end faces, outer circles, and inner holes, with a thickness smaller than the ring width and a specific cross-sectional shape (Wei Pengfei. Design and Simulation of Robotic Automated Welding System for Ring-Disc Parts [D]. 2016). These components serve as key foundational components for various high-end equipment such as rockets and missiles, including the front and rear joints of rocket engine combustion chamber shells, and have extensive and significant strategic needs in the defense and aerospace industries. Due to their small height-to-diameter ratio and large surface taper, these components have very complex geometry and cross-sectional profiles, posing a significant challenge to traditional ring-disc forming processes. Currently, advanced and efficient forming and manufacturing methods are lacking. Another method involves first obtaining a rectangular cross-section ring blank from bar stock through upsetting, punching, and bulging processes. Then, a rectangular cross-section disc blank of the same height as the final product is rolled on a ring mill. Finally, mechanical cutting is performed directly on the rectangular cross-section disc blank to obtain a large-tapered irregularly shaped ring-disc component. While this forming process is simple, the large cutting allowance results in extremely low material utilization, high costs, and reduced production efficiency. Furthermore, the machining process severely disrupts the overall flow lines of the metal, making it difficult to guarantee the product's mechanical properties. Therefore, current forming methods suffer from problems such as poor geometric accuracy, low material utilization, high costs, and difficulty in guaranteeing performance. Thus, new forming processes need to be developed for the production of such large-tapered irregular ring-shaped components. Summary of the Invention

[0003] In order to overcome the shortcomings of existing technologies such as poor geometric accuracy, low material utilization, high cost, and difficulty in guaranteeing performance, this invention proposes a method for blank preparation by rotary rolling composite forming of large-tapered irregular ring disk components.

[0004] The specific process of this invention is as follows:

[0005] Step 1: Determine the initial blank and intermediate blank dimensions.

[0006] Determine the outer diameter D0, inner diameter d0, and height h0 of the initial blank.

[0007] Determine the outer diameter D1, inner diameter d1, and height h1 of the intermediate blank.

[0008] Step 2: Process the initial blank.

[0009] After heating the bar stock to the forming temperature, it undergoes upsetting, punching, and bulging processes to obtain the initial blank.

[0010] In the upsetting process, the forging hammer of the forging press is pressed down at a uniform speed of 3~6 mm / s until the height of the bar stock is reduced to the designed initial blank height h0, and the upset stock is obtained.

[0011] In the punching process, the punch pressing speed is 2~4 mm / s.

[0012] In the bulging process, the billet with through holes is heated in the furnace to the forming temperature, and then the outer diameter and inner diameter of the billet with through holes are expanded to the designed outer diameter D0 and inner diameter d0 of the initial blank through a forging press.

[0013] Step 3: Form the intermediate blank.

[0014] The initial blank is heated to a forming temperature of 1000 °C in an electric resistance furnace and then transferred to the ring mill worktable for rolling. During the rolling process, the main roll rotates uniformly around its own axis at a speed of 1.8~2.5 rad / s, and the clamping rolls hold the initial blank placed on the ring mill worktable from both sides via a hydraulic device. The initial blank rotates under the friction of the main roll until its linear velocity synchronizes with that of the main roll. When the linear velocity of the initial blank synchronizes with that of the main roll, the upper conical roll begins to feed downwards along the axial direction at a speed of 0.4~0.7 mm / s; the lower conical roll rotates synchronously with the upper conical roll only around its own axis, rolling the initial blank axially. As the upper conical roll continues to feed axially, the initial blank undergoes a decrease in height and a gradual increase in both its inner and outer diameters due to plastic deformation. When the size of the initial blank reaches the designed intermediate blank size, the rolling process ends, and the desired intermediate blank is obtained.

[0015] The inner diameter of the intermediate blank is slightly smaller than that of the final spun blank, and the inner circle is slightly larger than that of the final spun blank.

[0016] Step 4: Shape the end face irregular ring rolling into a large taper irregular shaped spin-rolled blank.

[0017] After heating the intermediate blank obtained in step three to the forming temperature, it is transferred to the ring rolling mill worktable for end face irregular ring rolling to form the required spin-rolled blank.

[0018] During ring rolling, the area in contact with the main roll generates a frictional driving force to achieve stable driving of the ring; the area in contact with the core roll and tapered roll undergoes synergistic plastic deformation under radial-axial rolling, and the diameter expansion and precise shaping of the cross-sectional profile are achieved through the flow of material along the radial, axial and circumferential directions of the ring.

[0019] During the forming process, the main roll rotates uniformly around its own axis, and the intermediate blank rotates under the action of friction in contact with the main roll. The core roll moves radially towards the main roll, and after contacting the intermediate blank, it causes plastic deformation of its inner and outer surfaces, gradually thinning the wall thickness and gradually increasing the inner diameter. The clamping roll holds the intermediate blank placed on the ring mill worktable from both sides through a hydraulic device to stabilize the forming process. At the same time, the upper conical roll continuously feeds axially towards the end face of the blank. Under the axial feeding action of the upper conical roll, the part that first contacts the conical roll profile begins to undergo significant height reduction plastic deformation, while the end face near the inner hole of the blank undergoes less deformation. As the conical roll presses down further, when the entire end face of the blank is in contact with the conical roll profile, the blank begins to undergo plastic deformation with a continuous decrease in overall height. Subsequently, with the feeding of the core roll and the conical roll, under the synergistic effect of radial and axial deformation, the wall thickness of the blank continues to thin, the height continues to decrease, the diameter continues to increase, and the conical cross-section profile gradually takes shape. When the maximum outer diameter of the intermediate blank increases to the target size, the end face irregular ring rolling process ends, and the required large taper irregular shaped rotary rolled blank is finally formed.

[0020] The specific process for determining the intermediate blank dimensions is as follows:

[0021] The dimensions of the intermediate blank are determined based on the dimensions of the final shaped spin-rolled blank, and the volume of the intermediate blank is equal to the volume of the final shaped spin-rolled blank.

[0022] The maximum outer diameter of the final shaped spin-rolled blank is D. f1 The minimum outer diameter is D f2 The inner diameter of the constant-diameter section of the rotary-rolled blank is D. f The axial length of the constant diameter section is h. f The angle between the conical surface of the spin-rolled blank and the horizontal plane is α; the length from the inner edge to the outer edge of the conical surface on the upper surface of the final shaped spin-rolled blank is L;

[0023] In this example, the inner diameter of the intermediate blank is D1=81 mm, the height is h1=55 mm, and the wall thickness is b1=126 mm.

[0024] During the ring rolling process, the change in length of the tapered edge at the large end of the rotary rolled blank before and after deformation is ignored. Therefore, the outer diameter D1 of the intermediate blank is determined by the formula based on geometric relationships:

[0025] (1)

[0026] Where: D1 is the inner diameter of the intermediate blank, and b1 is the wall thickness of the intermediate blank.

[0027] Based on the outer diameter D1, inner diameter d1, and height h1 of the obtained intermediate blank, the volume V1 of the intermediate blank is calculated using formula (2): (2)

[0028] Where D1, d1, and h1 are the outer diameter, inner diameter, and height of the intermediate blank, respectively.

[0029] The profile of the upper tapered roll of the ring mill is a tapered surface that matches the outer cross-sectional profile of the final shaped spin-rolled blank; the main roll, core roll, and clamping roll are all straight-walled rectangular cross-section rolls.

[0030] This invention first determines the initial blank size and the intermediate blank size. Then, the initial blank is obtained from bar stock through upsetting, punching, and bulging processes. Next, the initial blank is rolled into an intermediate blank with inner and outer diameters slightly smaller than the final shaped spin-rolled blank, and an inner circle slightly larger than the final shaped blank through ring rolling. Finally, the intermediate blank undergoes uniform plastic deformation through ring rolling to obtain the final shaped spin-rolled blank. Compared to traditional processing methods, the processing method in this example significantly reduces the cutting amount, increases material utilization from 30% to 70%, and eliminates the need for developing new equipment; the ring rolling forming process can still be achieved using a ring rolling mill.

[0031] The ring undergoes uniform plastic deformation on the ring rolling mill, and has the following main characteristics:

[0032] The contact area between the ring and the main roll and the tapered roll undergoes cumulative radial-axial synergistic plastic deformation under circumferential progressive rolling, and its final shape is determined by the roll profile.

[0033] Because plastic deformation occurs only during circumferential progressive rolling, the shape of the ring changes uniformly. Furthermore, the amount of mechanical cutting during billet preparation is less, significantly improving material utilization compared to traditional processes.

[0034] Both billet preparation and final forming are carried out on the ring mill, eliminating the need for new equipment. This fully expands the role and function of the ring mill and provides new ideas for further exploring its effectiveness.

[0035] In the forming process of spin-rolled blanks, the blanks are ultimately formed by rolling with rollers. The geometry and dimensions of the spin-rolled blanks are guaranteed by the mold, and the forming process is stable, effectively avoiding defects such as distortion and ellipticity. In this invention, only a small amount of cutting is performed when the initial blank is formed from the bar stock. The taper of the spin-rolled blank is formed by tapered roller rolling. Compared with traditional mechanical cutting forming methods, this invention increases the material utilization rate from 40% to 70%, saving materials and thus reducing production costs by 20% to 25%. In addition, due to the smaller amount of mechanical cutting, the overall flow lines of the metal are not severely damaged, and the mechanical properties of the product are effectively guaranteed. This invention uses rollers to continuously roll the ring, ensuring that material deformation continues stably throughout the entire processing. At the same time, the fluidity of the metal is utilized to ensure that the diameter of the ring expands uniformly during processing, guaranteeing processing accuracy. Throughout the entire processing, under the synergistic action of the main roller and the tapered roller, the diameter of the ring increases to the ideal size, and the ring remains in constant contact with the tapered roller, ultimately resulting in a large-tapered irregular-shaped rotary rolled blank whose taper fits snugly against the upper tapered roller. This entire processing method ensures both processing accuracy and efficiency, reducing overall deformation costs by 30% to 50% compared to traditional processing methods. The technology proposed in this invention effectively solves the problems of poor roundness, low material utilization, high cost, and difficulty in guaranteeing performance in the current production of large-tapered irregular-shaped ring-disc components. Attached Figure Description

[0036] Figure 1 This is a schematic diagram illustrating the forming process of the large-tapered complex irregular-shaped ring-disc component in this invention; wherein, Figure 1 'a' refers to bar stock. Figure 1 b is the initial blank obtained after the expansion hole. Figure 1 c is the intermediate blank obtained through ring rolling. Figure 1 d is a large-tapered, irregularly shaped rotary rolled blank obtained through ring rolling.

[0037] Figure 2 This is a schematic diagram illustrating the forming principle of the present invention; wherein, Figure 2 a is a top view of the initial state of the ring rolling process; Figure 2 b is a cross-sectional view of the initial state of ring rolling; Figure 2 c is a cross-sectional view of the final state of the ring rolling.

[0038] Figure 3 This is a schematic diagram of the complex, irregularly shaped, rotary-rolled blank structure with a large taper, as shown in the embodiment.

[0039] Figure 4 This is a schematic diagram of the initial blank structure in the embodiment;

[0040] Figure 5 This is a schematic diagram of the intermediate blank structure in the embodiment;

[0041] Figure 6 A cross-sectional view was obtained to simulate the forming result of the spin-rolled blank.

[0042] Figure 7 This is a flowchart of the present invention.

[0043] In the diagram, 1 is the main roll; 2 is the clamping roll; 3 is the core roll; 4 is the upper conical roll; 5 is the lower conical roll; 6 is the intermediate blank; and 7 is the spin-rolled blank. Detailed Implementation

[0044] This embodiment describes a ring rolling composite forming process for preparing large-tapered irregular-shaped ring disk components. First, the initial blank size and intermediate blank size are determined. Second, the initial blank is obtained from bar stock through upsetting, punching, and bulging processes. Then, the initial blank is rolled into an intermediate blank with inner and outer diameters slightly smaller than the final shaped rotary-rolled blank, and an inner circle slightly larger than the final shaped blank. Finally, the intermediate blank undergoes uniform plastic deformation during rolling to obtain the desired large-tapered rotary-rolled blank.

[0045] In this embodiment, the structural shape of the formed large-tapered spin-rolled blank is as follows: Figure 3 As shown. Maximum outer diameter D of the formed spin-rolled blank. f1 =506 mm, minimum outer diameter D f2 =356.5 mm, inner diameter D of the equal diameter section f =266 mm, axial length h of the constant diameter section of the formed spin-rolled blank f =42 mm, the final shaped spin-rolled blank has a conical surface with an inner edge to outer edge length L=78 mm, and the angle α between the conical surface and the horizontal plane is 9°. The blank is made of 42CrMo material and the forming temperature is 1000 ℃.

[0046] The specific processing steps in this example are as follows:

[0047] Step 1: Determine the initial blank size and the intermediate blank size.

[0048] The initial blank is a ring blank made from bar stock through upsetting, punching and bulging processes. The cross-section of the ring blank is rectangular. The intermediate blank is a disc blank obtained from the initial blank through ring rolling. The cross-section of the disc blank is rectangular.

[0049] Determine the outer diameter D0, inner diameter D0, and height h0 of the initial blank.

[0050] Determine the outer diameter D1, inner diameter D1, and height h1 of the intermediate blank.

[0051] The specific process for determining the blank size is as follows:

[0052] Ⅰ Determine the intermediate blank dimensions:

[0053] The dimensions of the intermediate blank are determined based on the dimensions of the final shaped spin-rolled blank, and the volume of the intermediate blank is equal to the volume of the final shaped spin-rolled blank.

[0054] In this embodiment, according to design requirements, the maximum outer diameter D of the final formed spin-rolled blank is... f1 =506 mm, minimum outer diameter D f2 =356.5 mm, inner diameter D of the equal meridian section f =266 mm, axial length h of the equal diameter section of the formed rotary rolled blank f =42 mm, the length L=78 mm from the inner edge to the outer edge of the conical surface on the upper surface of the final shaped spin-rolled blank, and the angle α between the conical surface and the horizontal plane is 9°.

[0055] During the ring rolling process, the intermediate blank undergoes radial-axial plastic deformation to form the required taper. Simultaneously, during forming, the inner diameter of the intermediate blank expands, and the height at the inner circle decreases. Therefore, in this example, the inner diameter of the intermediate blank is D1 = 81 mm, the height is h1 = 55 mm, and the wall thickness is b1 = 126 mm.

[0056] During the ring rolling process, the change in length of the tapered edge at the large end of the rotary rolled blank before and after deformation is ignored. Therefore, the outer diameter D1 of the intermediate blank is determined by the formula based on geometric relationships:

[0057] D1 = d1 + 2b1 = 332 mm (1)

[0058] Where: d1 is the inner diameter of the intermediate blank, and b1 is the wall thickness of the intermediate blank.

[0059] Based on the outer diameter D1, inner diameter d1, and height h1 of the obtained intermediate blank, the volume V1 of the intermediate blank is calculated using formula (2):

[0060] (2)

[0061] Where D1, d1, and h1 are the outer diameter, inner diameter, and height of the intermediate blank, respectively.

[0062] II. Determine the initial blank dimensions:

[0063] Based on the principle of constant volume, the dimensions of the initial blank are determined. The volume of the initial blank is equal to the volume V1 of the intermediate blank. According to the method for determining the axial rolling blank dimensions of the ring blank disclosed in patent application number 201010164754.2, firstly, a reasonable range of values ​​for the rolling ratio k is determined based on the diameter of the mandrel used during rolling. Then, a suitable rolling ratio k is selected from this range. Finally, based on the principle of equal volume, the outer diameter D0, inner diameter d0, and height h0 of the initial blank are designed respectively.

[0064] In this embodiment, the diameter of the core roll used during rolling is 40 mm. The reasonable range of the determined rolling ratio k is 1 < k < 2.1, and the selected rolling ratio is k = 1.85. Based on this, the outer diameter of the initial blank is designed to be D0 = 320 mm, the inner diameter is d0 = 60 mm, and the height is h0 = 100 mm.

[0065] Step two: Process the initial blank.

[0066] According to the dimensions of the initial blank, the required bar stock is obtained through the blanking process. The bar stock is heated to the forming temperature of 1000 °C in a resistance furnace and then transferred to the workbench of the forging press. After upsetting, punching, and hole expanding processes, the initial blank is obtained.

[0067] Upsetting process: The axis of the bar stock is kept perpendicular to the anvil surface of the forging hammer to ensure that the metal flows uniformly along the radius direction of the bar stock during the upsetting deformation process. During the upsetting process, the forging hammer of the forging press presses down at a uniform upsetting speed of 3 - 6 mm / s. Under the action of the forging hammer of the forging press, the height of the bar stock decreases and the diameter increases until the height of the bar stock decreases to 255 mm, and the upsetting process is completed, obtaining the upset blank.

[0068] In this embodiment, the pressing speed of the forging hammer of the forging press is 4 mm / s.

[0069] Punching process: The diameter of the punch is 30 mm. The pressing speed of the punch is 1 - 2 mm / s. After punching a blind hole in the upset blank, the blank is flipped 180° and the punch continues to press down at a speed of 1 - 2 mm / s to punch off the web, completing the punching process and obtaining the blank with a through hole. When punching the blind hole and the web, the punch should be placed in the center of the blank to prevent uneven wall thickness of the blank after punching due to punching eccentricity.

[0070] In this embodiment, the pressing speed of the punch is 3 mm / s.

[0071] Hole expanding process: After punching, the obtained blank with a through hole is reheated to the forming temperature of 1000 °C in a furnace and then transferred to the workbench of the forging press. A punch with a diameter the same as the inner diameter d0 of the initial blank is used. Under the action of the forging press, the punch passes through the inner hole of the blank with a through hole, expanding the hole diameter and the outer diameter of the blank with a through hole obtained after punching, obtaining the initial blank.

[0072] In this embodiment, the diameter of the punch is the same as the inner diameter d0 of the initial blank, which is 40 mm. Under the action of the forging press, the punch passes through the inner hole of the blank with a through hole, expanding the hole diameter of the blank with a through hole obtained after punching from 30 mm to 40 mm and the outer diameter to 320 mm, finally obtaining the initial blank with an outer diameter D0 = 320 mm, an inner diameter d0 = 60 mm, and a height h0 = 100 mm.

[0073] Step 3: Form the intermediate blank.

[0074] The initial blank is heated to a forming temperature of 1000 °C in an electric resistance furnace and then transferred to the ring mill worktable for rolling. During the rolling process, the main roll rotates uniformly around its own axis at a speed of 1.8~2.5 rad / s, and the clamping rolls hold the initial blank placed on the ring mill worktable from both sides via a hydraulic device. The initial blank rotates under the friction of the main roll until its linear velocity synchronizes with that of the main roll. When the linear velocity of the initial blank synchronizes with that of the main roll, the upper conical roll begins to feed downwards along the axial direction at a speed of 0.4~0.7 mm / s; the lower conical roll rotates synchronously with the upper conical roll only around its own axis, rolling the initial blank axially. As the upper conical roll continues to feed axially, the initial blank undergoes a decrease in height and a gradual increase in both its inner and outer diameters due to plastic deformation. When the size of the initial blank reaches the designed intermediate blank size, the rolling process ends, and the desired intermediate blank is obtained.

[0075] In this embodiment, the rotational speed of the main roller around its own axis is 2.0 rad / s; the axial feed speed of the upper conical roller is 0.5 mm / s.

[0076] The dimensions of the intermediate blank are determined in step one. The inner diameter of the intermediate blank is smaller than the inner diameter of the equal-diameter section of the final shaped spin-rolled blank, i.e., D1 = 81 mm. The height of the intermediate blank is greater than the axial length of the equal-diameter section of the final shaped spin-rolled blank, i.e., h1 = 55 mm. In this embodiment, the outer diameter D1 of the intermediate blank is calculated using formula (3), and D1 = 332 mm. This satisfies the condition that the outer diameter of the intermediate blank is less than the maximum outer diameter of the final shaped spin-rolled blank, i.e., D1... <D f1 =506 mm.

[0077] Step 4: Shape the end face irregular ring rolling into a large taper spin-rolled blank.

[0078] After heating the intermediate blank to a forming temperature of 1000 ℃ in a resistance furnace, it is transferred to the ring rolling mill worktable for end face irregular ring rolling to obtain the required large taper irregular shaped rotary rolled blank.

[0079] The ring rolling mill includes a main roll 1, a core roll 2, a clamping roll 3, an upper conical roll 4, a lower conical roll 5, and an intermediate blank 6. The main roll 1, core roll 2, and clamping roll 3 are all rectangular in shape; the upper conical roll 4 has a conical surface that matches the outer cross-sectional profile of the final shaped spin-rolled blank; and the lower conical roll 5 is a traditional conical roll with a 30° apex angle and an isosceles trapezoidal cross-section.

[0080] When installing the spinning blank, the lower end faces of the main roll 1, core roll 2, and clamping roll 3 are all on the same plane as the working platform of the ring mill. The intermediate blank 6 is placed on the working table, so that it is in surface contact with the main roll 1 and core roll 2. The two clamping rolls 3 are symmetrically distributed on both sides of the spinning blank, and remain tangent to the outer circle of the intermediate blank 6 throughout the forming process. The upper conical roll 4 is always in contact with the outer circle of the intermediate blank 6, and the lower conical roll 5 is always horizontally tangent to the intermediate blank 6.

[0081] During the ring rolling process, the area in contact with the main roll 1 generates a frictional driving force to achieve stable driving of the ring; the area in contact with the core roll 2 and the upper cone roll 4 undergoes synergistic plastic deformation under radial-axial rolling, and the diameter expansion and precise shaping of the cross-sectional profile are achieved through the flow of material along the radial, axial and circumferential directions of the ring.

[0082] During the forming process, the main roll 1 rotates uniformly around its own axis at a speed of w = 1.8~2.5 rad / s. The intermediate blank 6 rotates under the action of friction in contact with the main roll 1. The core roll 2 moves radially towards the main roll 1 at a speed of v = 0.5~1.0 mm / s. After contacting the intermediate blank 6, it causes plastic deformation on its inner and outer surfaces, gradually thinning the wall thickness and gradually increasing the inner diameter. The clamping roll 3 holds the intermediate blank 6, which is placed on the ring mill worktable, from both sides through a hydraulic device to stabilize the forming process. At the same time, the upper conical roll 4 continuously feeds axially towards the end face of the blank. Under the axial feeding action of the upper conical roll 4, the part that first contacts the conical roll profile begins to undergo significant height reduction plastic deformation, while the end face near the inner hole of the blank undergoes less deformation. As the conical roll presses down further, when the entire end face of the blank is in contact with the conical roll profile, the blank begins to undergo overall height reduction plastic deformation. Subsequently, as the core roll and tapered roll are fed, under the synergistic effect of radial and axial deformation, the wall thickness of the billet continues to decrease, the height continues to decrease, and the diameter continues to increase, gradually forming the tapered cross-section profile. When the maximum outer diameter of the intermediate billet 6 increases to 556 mm, the end-face irregular ring rolling process ends, and the required large-taper irregular shaped rotary rolled billet 7 is finally formed.

Claims

1. A method for preparing a billet using a ring rolling composite forming process for large-tapered irregular-shaped ring disk components, the specific process of which is as follows: Step 1: Determine the initial blank size and the intermediate blank size; Determine the outer diameter D0, inner diameter d0, and height h0 of the initial blank; Determine the outer diameter D1, inner diameter d1, and height h1 of the intermediate blank; Step 2: Process the initial blank; After heating the bar stock to the forming temperature, it undergoes upsetting, punching, and bulging processes to obtain the initial blank; Step 3: Form the intermediate blank; After the initial blank is heated to the forming temperature, it is transferred to the ring mill worktable for rolling. During the rolling process, the main roll of the ring mill rotates uniformly around its own axis at a speed of 1.8~2.5 rad / s. The clamping roll holds the initial blank placed on the ring mill worktable from both sides through a hydraulic device. The initial blank rotates under the friction of the main roll until the linear velocity of the initial blank is synchronized with the linear velocity of the main roll. When the linear velocity of the initial blank is synchronized with the linear velocity of the main roll, the upper conical roll begins to feed downward along the axial direction at a speed of 0.4~0.7 mm / s. The lower conical roll rotates synchronously with the upper conical roll only around its own axis, rolling the initial blank axially. As the upper conical roll continues to feed axially, the height of the initial blank decreases, and the inner and outer diameters increase uniformly under the action of the rolling force. When the size of the initial blank reaches the designed intermediate blank size, the rolling process ends, and the required intermediate blank is obtained. The inner diameter of the intermediate blank is slightly smaller than that of the final large-tapered spin-rolled blank, and the inner circle is slightly larger than that of the outer diameter. Step 4: Shape the end face irregular ring rolling into a large taper irregular shaped spin-rolled blank; After heating the intermediate blank obtained in step three to the forming temperature, it is transferred to the ring mill worktable for rolling and forming to obtain the required large taper spin-rolled blank. During ring rolling, frictional driving force is generated in the area in contact with the main roll to achieve stable driving of the ring; while the area in contact with the core roll and tapered roll undergoes synergistic plastic deformation under radial-axial rolling, and the diameter expansion and precise shaping of the cross-sectional profile are achieved through the flow of material along the radial, axial and circumferential directions of the ring. During the forming process, the main roll rotates uniformly around its own axis, and the intermediate blank rotates under the action of friction in contact with the main roll. The core roll moves radially towards the main roll, and after contacting the intermediate blank, it causes plastic deformation of its inner and outer surfaces, gradually thinning the wall thickness and gradually increasing the inner diameter. The clamping roll holds the intermediate blank placed on the ring mill worktable from both sides of the intermediate blank through a hydraulic device to stabilize the forming process. At the same time, the upper conical roll continuously feeds axially towards the end face of the blank. Under the axial feeding action of the upper conical roll, the part that first contacts the conical roll profile begins to undergo significant height reduction plastic deformation, while the end face near the inner hole of the blank deforms less. As the conical roll presses down further, when the entire end face of the blank contacts the conical roll profile, the blank begins to undergo plastic deformation with a continuous decrease in overall height. Subsequently, with the feeding of the core roll and the conical roll, under the synergistic effect of radial and axial deformation, the wall thickness of the blank continues to thin, the height continues to decrease, the diameter continues to increase, and the conical cross-section profile gradually takes shape. When the maximum outer diameter of the intermediate blank increases to the target size, the end face irregular ring rolling process ends, and the required large taper irregular shaped rotary rolled blank is finally formed.

2. The specific process for determining the intermediate blank size in the ring rolling composite forming process of the large-tapered irregular ring-shaped component as described in claim 1 is as follows: The dimensions of the intermediate blank are determined based on the dimensions of the final spin-rolled blank, and the volume of the intermediate blank is equal to the volume of the final rolled spin-rolled blank. The maximum outer diameter of the final shaped spin-rolled blank is D. f1 The minimum outer diameter is D f2 The inner diameter of the constant-diameter section of the rotary-rolled blank is D. f The axial length of the constant diameter section is h. f The angle between the conical surface of the spin-rolled blank and the horizontal plane is α°; the length from the inner edge to the outer edge of the conical surface on the upper surface of the final shaped spin-rolled blank is L; In this example, the inner diameter of the intermediate blank is D1=81 mm, the height is h1=55 mm, and the wall thickness is b1=126 mm. During the ring rolling process, the change in length of the tapered edge at the large end of the rotary rolled blank before and after deformation is ignored. Therefore, the outer diameter D1 of the intermediate blank is determined by the formula based on geometric relationships: (1) in: D1 is the inner diameter of the intermediate blank, and b1 is the wall thickness of the intermediate blank. Based on the outer diameter D1, inner diameter d1, and height h1 of the obtained intermediate blank, the volume V1 of the intermediate blank is calculated using formula (2): (2) Where D1, d1, and h1 are the outer diameter, inner diameter, and height of the intermediate blank, respectively.

3. The billet preparation method of the large-tapered irregular ring disc type component ring rolling composite forming process as described in claim 1, wherein the profile of the upper tapered roll of the ring rolling mill is a tapered surface that matches the cross-sectional profile of the final formed spin-rolled billet; the main roll, core roll and clamping roll are all straight-walled rectangular cross-section rolls.

4. The billet preparation method for the ring rolling composite forming process of large-tapered irregular ring-disc type components as described in claim 1, wherein the initial blank processing involves: In the upsetting process, the forging hammer of the forging press presses down at a uniform upsetting speed of 3~6 mm / s until the height of the bar stock is reduced to the designed initial blank height h0, and the upset patty is obtained. In the punching process, the downward pressing speed of the punch is 1~2 mm / s; In the hole expansion process, after the blank with through holes is heated to the forming temperature in the furnace, the outer diameter of the blank with through holes is expanded to the designed outer diameter D0 of the initial blank, and the inner diameter of the blank with through holes is expanded to the designed inner diameter D0 of the initial blank.

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