A deep-cavity thin-wall bracket forging, a forging die and a forming method

Abstract

The present application relates to the technical field of forging forming, and particularly relates to a deep-cavity thin-wall support forging, a forging die and a forming method. A heated round bar is roll-forged to obtain a preform, and the roll-forged preform is cleaned of the oxide skin. The preform is placed in a pre-forging cavity of a forming die for pre-forging forming. After the pre-forging is completed, the pre-forging piece is transferred to a finish-forging cavity of the same forming die for finish-forging forming to obtain a left-right symmetrical finish-forging piece. The left-right symmetrical finish-forging piece is placed in a trimming die frame for trimming to remove the flash. The left-right symmetrical finish-forging piece after cold sizing is cut by a cutting device from a shunt bin to be separated into two independent single-piece forgings. The forming defects are eliminated, the yield of forgings is improved to a level that can be stably produced, the thickness tolerance of the functional surface of the product is ensured, the spot welding current is stable and the welding strength is ensured, the assembly demand is met, the dependence on subsequent machining is reduced, the material cost is reduced, and the die life is prolonged.

Description

Technical Field

[0001] This invention relates to the field of forging technology, and in particular to a deep cavity thin-walled support forging, forging die, and forming method. Background Technology

[0002] Deep-cavity, thin-walled steel brackets are key structural components in the new energy vehicle sector. According to the standard GB / T 12362-2016 "Tolerances and Machining Allowances for Steel Forgings", the shape complexity coefficient of such forgings reaches level S4 (complex level), further increasing the difficulty of forging production.

[0003] In the existing technology, the forging production of such parts mainly faces the following systemic challenges:

[0004] 1. During the forging and filling process, the metal has a long flow path and uneven resistance distribution. In particular, the right square end face is thinner, making material flow extremely difficult and prone to edge stepping. If bar stock is heated and forged in one step (the maximum equivalent diameter of the product is about Φ65mm), defects such as folding and incomplete filling are also very likely to occur, directly resulting in a low yield.

[0005] 2. The functional surfaces of the product need to be spot-welded to the other parts, which places extremely stringent requirements on wall thickness accuracy. Uneven wall thickness or a thickness exceeding the 2.6mm tolerance can easily cause fluctuations in the spot welding current, resulting in weak welds or weld failures. Traditional forging processes are affected by factors such as edge deformation and cooling stress, making it difficult to accurately control the dimensional accuracy of such precision assembly surfaces. They often require extensive subsequent machining for correction, which is not only inefficient but may also damage the internal metal flow lines of the parts, affecting structural performance.

[0006] In addition, the right square end face of the finished forging is relatively thin, making it difficult for material to flow in this area during forging, which can easily lead to risks such as edge tack and short die life.

[0007] 3. To ensure complete filling of complex cavities, traditional processes typically use large-margin blanks for one-step final forging, resulting in a material utilization rate as low as 30%, causing a large amount of material waste. At the same time, the forming of complex structures requires the application of huge tonnage loads, and the violent metal flow will have a strong impact on the mold. In particular, stress concentration is prone to occur in the protruding parts of the deep cavity of the mold, which will lead to early wear, plastic deformation or even cracking of the mold, significantly shortening the service life of the mold and increasing production costs and production risks. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to provide a deep cavity thin-walled bracket forging, forging die, and forming method that ensures product functional requirements, improves yield, material utilization, and mold life.

[0009] The technical solution adopted by this invention to solve its technical problem is: a deep cavity thin-walled support forging, comprising a forging body, the forging body being integrally formed, the forging body comprising...

[0010] Deep cavity area,

[0011] The shallow cavity is connected to the deep cavity through an arc-shaped transition section to form a smooth metal flow channel, avoiding eddies or shearing folds at sharp turns.

[0012] A square side plate is located at the end of the shallow cavity portion, and the square side plate is positioned away from the deep cavity portion;

[0013] A V-shaped notch is formed at the connection between the deep cavity and the shallow cavity to reduce the peak resistance of the metal filling. Both the deep cavity and the shallow cavity have local opening structures at the ends furthest from each other.

[0014] The opening edges of the deep cavity and the shallow cavity are provided with outwardly extending convex edges, and the top surfaces of the deep cavity and the shallow cavity are both formed with burr bridges at their opposite corners.

[0015] Furthermore, the depth of the deep cavity is less than or equal to 70 mm, and the wall thickness of the deep cavity is 3.7 to 4.3 mm. Precise wall thickness control is the basis for ensuring the overall structural rigidity and functional surface accuracy, and avoids local deformation caused by uneven wall thickness.

[0016] A forging die for a deep-cavity thin-walled support forging as described in any of the preceding claims, comprising a die body, the die body including...

[0017] upper mold,

[0018] The lower die, positioned opposite the upper die, forms a closed cavity space through mold closing, providing constraint and forming force for the plastic deformation of the metal. After the lower and upper dies are closed, they form a pre-forging cavity and a precision forging cavity arranged side by side along the length of the mold, realizing the integration of the two key processes of pre-forging and precision forging on the same set of molds, reducing mold change time, and improving production efficiency and centering. The layout of both the pre-forging cavity and the precision forging cavity is a two-part structure of one mold, ensuring the finished quality of the most precision forged part, improving yield, production efficiency, and material utilization.

[0019] A flow divider is provided in the middle of the cavity of the precision forging mold for two parts. It is used to contain the excess material during precision forging, which significantly reduces the peak stress of the mold, improves the mold life and prevents cracking. The flow divider can be removed in the subsequent cutting process.

[0020] The locking structure is located on the contact surface between the upper and lower dies. It is used to position and guide the upper and lower dies during the mold closing process, resist the huge horizontal misalignment force generated during forging, prevent the die cavity from misalignment, and thus ensure the dimensional accuracy of the forging, the uniformity of the wall thickness, and the protection of the die itself from damage.

[0021] Furthermore, the depth of the deep cavity of the pre-forging cavity is less than the depth of the deep cavity of the precision forging cavity, and the difference between the volume of the bottom of the deep cavity of the pre-forging cavity and the volume of the corresponding bottom of the deep cavity of the precision forging cavity is within 5%.

[0022] Furthermore, the lower die is provided with a locking mechanism at the edges of the flash bridges at both ends of the pre-forging cavity. The locking mechanism is a protrusion with a width of 7-12mm and a height of 1.5-3mm, which is used to restrict the flow of the blank at both ends, so as to fill the die cavity and force more metal to flow to the deep cavity in the middle of the cavity under pressure, and preferentially fill the most difficult area to fill, thereby effectively preventing material shortage in the deep cavity.

[0023] Furthermore, a material feeding groove is provided at the entrance of the deep cavity of the pre-forging cavity in the lower die to facilitate the placement of the roll-forged billet into the pre-forging cavity, ensure accurate positioning, prevent billet rotation, and improve operational stability, production cycle time, and forming consistency.

[0024] Furthermore, the draft angle of the pre-forging cavity is 0.5° to 1° larger than that of the precision forging cavity, and the transition fillet of the pre-forging cavity is larger than that of the precision forging cavity, which reduces the resistance to metal flow and prevents folding during the pre-forging stage.

[0025] Furthermore, the width of the diversion compartment is 2-5mm and the height is 3-5mm.

[0026] Furthermore, the locking structure includes a protruding guide portion provided in the upper mold and a corresponding groove portion provided in the lower mold.

[0027] A forming method, employing a forging die as described above, comprises the following specific steps:

[0028] Step 1: Material preparation: Obtain round bars of the predetermined specifications;

[0029] Step 2: Heating: Induction heating of the round bar to the forging temperature;

[0030] Step 3: Roll forging: The heated round bar is roll forged to obtain a preform, and the oxide scale is removed from the forged preform.

[0031] Step 4: Pre-forging: The pre-formed billet is placed into the pre-forging cavity of the forming mold and pre-forging is performed to obtain a pre-forged part that is symmetrical on both sides; wherein, the pre-formed billet is positioned by the feeding groove and its flow at both ends is restricted by the locking mechanism;

[0032] Step 5: Precision forging: After pre-forging, the pre-forged part is transferred to the precision forging cavity of the same forming mold for precision forging to obtain a symmetrical precision forging part; the excess material generated during precision forging flows into the distribution chamber.

[0033] Step 6: Trimming: Place the symmetrical precision forgings into the planing die for trimming to remove the flash;

[0034] Step 7: Shot blasting: Perform surface shot blasting on the precision forgings after edge trimming to remove surface oxide scale;

[0035] Step 8: Cold forming: The functional surfaces of the symmetrical precision forgings are formed at room temperature to ensure their thickness and contour accuracy;

[0036] Step 9: Cutting: Install the cold-formed symmetrical precision forgings on the mounting fixture, and cut them from the flow divider into two independent single forgings using a cutting device;

[0037] Step 10: Clean, prevent rust, and store in the warehouse.

[0038] The beneficial effects of this invention are:

[0039] 1. It fundamentally and systematically eliminates forming defects such as edge stepping, folding, and incomplete filling, thereby improving the forging yield of such complex structural parts to a level that can be stably mass-produced;

[0040] 2. It can reliably and stably guarantee that the thickness tolerance of 7 functional surfaces of the product is within 2.6±0.1mm, ensuring stable spot welding current and welding strength, directly meeting the assembly requirements of high reliability fields such as new energy vehicles, and reducing the reliance on expensive and inefficient subsequent machining.

[0041] 3. Material utilization rate increased from about 30% to about 70%, significantly reducing raw material costs; mold life was extended several times, reducing mold consumption, replacement frequency and production downtime, significantly reducing unit production cost and improving production stability.

[0042] 4. This transforms the manufacturing of S4-level complex deep-cavity thin-walled stents from a high-difficulty, high-scrap-rate, and high-cost challenge into a mass production process with stable quality, controllable efficiency, and economic feasibility, giving it strong market competitiveness and industrialization promotion value. Attached Figure Description

[0043] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0044] Figure 1 This is a schematic diagram of the structure of the forging of the present invention;

[0045] Figure 2 This is the present invention. Figure 1A structural diagram from another direction;

[0046] Figure 3 This is a front view of the forging of the present invention;

[0047] Figure 4 This is a cross-sectional view of the present invention along direction AA;

[0048] Figure 5 This is a cross-sectional view of the present invention along the BB direction;

[0049] Figure 6 This is a cross-sectional view of the present invention along the CC direction;

[0050] Figure 7 This is a schematic diagram of the forging die of the present invention;

[0051] Figure 8 This is a schematic diagram of the structure of the upper die of the forging mold of the present invention;

[0052] Figure 9 This is a schematic diagram of the structure of the lower die of the forging mold of the present invention;

[0053] Figure 10 This is a partial enlarged view of point A in the present invention;

[0054] Figure 11 This is a front view of the lower die of the forging mold of the present invention;

[0055] Figure 12 This is a cross-sectional view at point DD of the present invention;

[0056] Figure 13 This is a cross-sectional view of the EE section of the present invention;

[0057] Figure 14 This is a schematic diagram of the structure after roll forging according to the present invention;

[0058] Figure 15 This is a schematic diagram of the structure of the pre-forged part produced by the present invention;

[0059] Figure 16 This is a schematic diagram of the structure of the precision forging produced by the present invention;

[0060] Figure 17 This is a flowchart of the molding method of the present invention;

[0061] In the diagram: 1. Upper die, 13. Protruding guide section, 2. Lower die, 21. Groove section, 3. Pre-forging cavity, 4. Precision forging cavity, 5. Diverter chamber, 6. Material locking mechanism, 7. Discharge groove, 8. Deep cavity section, 9. Shallow cavity section, 10. Square side flat section, 11. V-shaped notch, 12. Flash bridge. Detailed Implementation

[0062] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0063] like Figure 1 and Figure 2 As shown in the figure, the cross-sectional surface is the machined surface, and the 7 black-painted surfaces are the functional surfaces of the product, which need to be spot-welded to the other parts for assembly.

[0064] like Figures 1-6 The forged deep-cavity thin-walled support includes a forging body, which is integrally formed, and the forging body comprises sequentially connected components.

[0065] Deep cavity section 8,

[0066] The shallow cavity 9 is connected to the deep cavity 8 as a whole through an arc-shaped transition section;

[0067] A square side flat portion 10 is located at the end of the shallow cavity portion 9, and the square side flat portion 10 is disposed away from the deep cavity portion 8;

[0068] A V-shaped notch 11 is formed at the connection between the deep cavity portion 8 and the shallow cavity portion 9. Both the deep cavity portion 8 and the shallow cavity portion 9 have local opening structures at the ends away from each other.

[0069] The opening edges of the deep cavity portion 8 and the shallow cavity portion 9 are provided with outwardly extending convex edges, and the top surfaces of the deep cavity portion and the shallow cavity portion are each provided with a fly-edge bridge 12 at their opposite corners.

[0070] like Figure 4 As shown, this cross-section reveals the internal structure of the deep cavity portion 8; the deep cavity portion 8 has a horizontal cavity bottom surface and inner cavity walls that are all inclined surfaces, each inner cavity wall having a specific, optimized draft angle relative to the vertical reference plane:

[0071] The angle α between the left cavity wall of the deep cavity 8 and the vertical reference plane is 1° to 3°. The smaller angle is conducive to ensuring the verticality of the side wall.

[0072] The angle β between the right cavity wall of the deep cavity section 8 and the vertical reference plane is 40° to 50°. The larger angle facilitates metal flow and demolding.

[0073] The angle γ between the front and rear cavity walls of the deep cavity section 8 and the vertical reference plane is 4° to 7°, which provides the necessary draft angle while ensuring structural strength.

[0074] The depth of the deep cavity 8 is less than or equal to 70 mm, and the wall thickness of the deep cavity is 3.7 to 4.3 mm. This uniform and controlled wall thickness is the basis for ensuring the overall rigidity of the forging and the accuracy of the subsequent functional surfaces.

[0075] like Figure 4 As shown, the V-shaped notch 11 has two sides, and the angle δ between the side of the deep cavity 8 and the vertical reference plane is 16° to 20°.

[0076] The angle ε between one side of the shallow cavity 9 and the vertical reference plane is 45° to 55°.

[0077] This V-shaped notch 11 is one of the core designs for optimizing metal flow. During the forging process, it acts as a directional flow channel, effectively distributing and guiding the metal material according to the set angles δ and ε, so that the material can synchronously and smoothly fill the deep cavity portion 8 and the shallow cavity portion 9, thereby fundamentally avoiding defects such as folding or incomplete filling at the joint.

[0078] As Figure 4 and Figure 6 As shown, the shallow cavity portion 9 has a horizontal cavity bottom surface and an inner cavity wall that is entirely inclined.

[0079] The angle θ between the right wall of the shallow cavity 9 and the vertical reference plane is 60° to 70°.

[0080] The angle η between the front and rear side walls of the shallow cavity 9 and the vertical reference plane is 10° to 13°.

[0081] These angle designs ensure good formability and demolding properties for the shallow cavity section 9.

[0082] Meanwhile, the cross-section clearly shows that the top surface of the square side plate 10 is lower than the top surface of the shallow cavity portion 9, and the square side plate 10 has a partial notch, the bottom surface of which is flush with the top inclined surface of the right side wall of the shallow cavity portion 9. This design makes the material distribution in this area more reasonable, reduces uneven shrinkage, and helps stabilize the overall dimensions. Figure 4 As shown, the height H3 of the deep cavity portion 8 is greater than the sum of the height difference H4 between the top surface of the shallow cavity portion 9 and the top surface of the square side plate portion 10 and the height H5 of the square side plate portion.

[0083] Among them, the reverse side of the wing bridge 12 of the deep cavity part 8 and the shallow cavity part 9, the reverse side of the square side flat part 10, and the bottom surface of the cavity of the deep cavity part 8 are all product functional surfaces, and the thickness tolerance of the product functional surfaces is 2.4 to 2.7 mm.

[0084] The final product's functional surface thickness, maximum cavity depth, and cavity wall thickness all meet the design requirements.

[0085] Working principle:

[0086] The structure of this forging is a design result closely coupled with its manufacturing process. During the pre-forging and precision forging processes, the specific angles (α, β, γ, δ, ε, θ, η) of the aforementioned parts together constitute an optimized metal flow guiding system, ensuring the complete filling of complex cavities.

[0087] After forging and subsequent processing, the forging has multiple high-precision functional surfaces formed by the reverse side of the flash bridge 12, the reverse side of the square side flat part 10, and the bottom surface of the deep cavity part 8.

[0088] Through precise forging structure design (such as uniform wall thickness and balanced geometric relationship H3>H4+H5) and subsequent cold forming process, the thickness of these functional surfaces is strictly controlled within the tolerance range of 2.4 to 2.7 mm, thereby meeting the stringent requirements for high-reliability spot welding assembly with other parts.

[0089] like Figures 7-13 The forging die for a deep-cavity thin-walled support forging shown includes a die body, the die body comprising...

[0090] Upper die 1, the bottom surface of upper die 1 is machined with a pre-forged upper cavity and a precision forged upper cavity;

[0091] The lower die 2 has a pre-forging lower cavity and a precision forging lower cavity on its top surface, which are corresponding to those of the upper die 1 and are set opposite to the upper die 1.

[0092] After the lower mold 2 and the upper mold 1 are closed, a pre-forging cavity 3 and a precision forging cavity 4 are formed and arranged side by side along the length of the mold. The pre-forging cavity 3 and the precision forging cavity 4 are arranged on one mold with a total width of 400mm, which can meet the mold strength requirements.

[0093] To improve material utilization, reduce machining allowance on square end faces, increase production efficiency, and avoid misalignment forces during forging, both the pre-forging cavity 3 and the precision forging cavity 4 are designed with a two-piece structure in one die. This layout improves the production efficiency of a single forging and also improves the quality of the forged product. In addition, the two-piece design allows for the use of roll forging to optimize the billet.

[0094] A flow divider 5 is provided in the middle of the cavity of the precision forging mold 4, which contains excess material during precision forging. The flow divider 5 is a groove structure with a width of 2-5 mm and a height of 3-5 mm. Its working principle is that in the final stage of precision forging, the trace amount of excess metal in the cavity that can no longer participate in plastic deformation will be squeezed into this flow divider, thereby avoiding the mold from overload deformation or cracking due to the extremely high hydrostatic pressure, and significantly improving the mold life. The flow divider 5 can be removed in subsequent cutting and machining.

[0095] Because the precision forging cavity of the upper die 1 is relatively high, a locking structure is set on the contact surface between the upper die 1 and the lower die 2 to improve the utilization rate of the die. It is used to position and guide the upper die 1 and the lower die 2 during the die closing process to prevent the die cavity from shifting. The upper die 1 and the lower die 2 achieve precise guidance and die closing positioning through the locking structure, avoid the misalignment force generated during forging, ensure the accuracy of the forging, and facilitate the installation of the die.

[0096] Several ejector pins are installed on the upper mold 1 and the lower mold 2.

[0097] like Figure 6 , Figure 7 As shown, the depth H1 of the deep cavity of the pre-forging cavity 3 is less than the depth H2 of the deep cavity of the precision forging cavity 4, which can effectively improve the strength of the pre-forging die and withstand severe deformation.

[0098] Its design principle is that by forming a shallower deep cavity through pre-forging, the pre-forging tonnage can be significantly reduced, the load on the die in the pre-forging step can be reduced, and sufficient filling space is reserved for the precision forging step, so as to guide the metal to fill the deep cavity in an orderly and stable manner during precision forging and avoid folding.

[0099] In addition, the volume difference between the bottom of the pre-forging cavity 3 and the bottom of the corresponding deep cavity of the precision forging cavity 4 is within 5%. During forming, the deep cavity 8 preferentially fills the precision forging cavity 4 to avoid defects such as edge treading and side wall depression in this part. Excess metal in this part can flow to the flash 12 and the flow distribution chamber 5, which can reduce stress concentration in the corresponding part of the mold and avoid mold deformation.

[0100] like Figure 4 As shown, the lower die 2 has a locking mechanism 6 set at the edges of the flash bridges at both ends of the pre-forging cavity 3. The locking mechanism 6 is a protruding mechanism with a width of 7 to 12 mm and a height of 1.5 to 3 mm, which is used to restrict the flow of the blanks at both ends.

[0101] Its working principle is as follows: In the pre-forging step, the protrusion can physically block the metal at both ends of the roll forging billet from flowing laterally into the flash bin too quickly, thereby forcing more pressure to act on the middle of the billet, driving the metal to flow preferentially to and fill the deep cavity of the pre-forging cavity 3, providing a good material distribution basis for subsequent precision forging, and effectively preventing material shortage in the deep cavity during precision forging.

[0102] like Figure 4 As shown, a feeding groove 7 is provided at the entrance of the deep cavity of the pre-forging cavity 3 in the lower die 2. It plays a positioning and receiving role when placing the billet, ensuring that the billet can be placed into the pre-forging cavity quickly, accurately and in the same direction, preventing the billet from rotating or shifting before impact, and ensuring the stability of the production process and the consistency of the forgings.

[0103] The draft angle of the pre-forging cavity 3 is 0.5° to 1° larger than that of the precision forging cavity 4. The transition fillet of the pre-forging cavity 3 is larger than that of the precision forging cavity 4. The larger draft angle and fillet can significantly reduce the flow resistance of the metal in the pre-forging stage, making it easier for the material to fill the cavity and transition smoothly, thereby minimizing the risk of folding of the pre-forging part and providing a defect-free blank for precision forging.

[0104] like Figure 8 and Figure 9 As shown, the locking structure includes a protruding guide portion 13 provided on the upper mold 1 and a corresponding groove portion 21 provided on the lower mold 2. The locking structure contacts and guides the mold during mold closing to ensure precise alignment of the upper and lower molds, effectively resist the horizontal misalignment force generated during forging, ensure the accuracy of the forging and protect the mold.

[0105] The thickness of the flash bridge portion of the pre-forging cavity 3 is 0.5 to 2 mm greater than that of the flash bridge portion of the corresponding precision forging cavity 4. Increasing the flash thickness reduces the pre-forging tonnage and facilitates the smooth flow of excess material along the flash during precision forging.

[0106] Work process:

[0107] Step 1: Position the preformed billet obtained by roll forging into the feeding groove 7 of the lower die 2;

[0108] Step 2: The upper die 1 moves downwards, guided by the locking structure, and closes with the lower die 2 for pre-forging; the material locking mechanism 6 restricts the metal flow at both ends, forcing the material to fill the deep cavity and form a pre-forged part (its shape is as follows). Figure 15 (Illustration)

[0109] Step 3: Remove the pre-forged part, clean it, and transfer it to position 4 of the precision forging cavity in the same mold;

[0110] Step 4: The upper die 1 descends again to close, performing precision forging (final forging). The pre-forged part is finally formed in the precision forging cavity 4, and a small amount of excess metal flows into the distribution chamber 5, resulting in a precision forging (its shape is as follows). Figure 16 (Illustration)

[0111] Step 5: After the mold is opened, the precision forging is ejected by the ejector pin (not shown in the figure, but it is a conventional design), completing one forging cycle;

[0112] Step 6: After the precision forging is trimmed, shot blasted, cold-formed and cut (separating the two parts of one mold and removing the material handle of the distribution hopper), the finished forging is obtained.

[0113] A forming method, comprising a forging die as described in any of the preceding claims, comprising the following steps:

[0114] Step 1: Blanking: Obtain round bars of the predetermined specifications. The diameter of the round bars should be 50-60mm to meet the forging requirements. The round bars of the above diameter are then rolled to obtain... Figure 16 The material utilization rate of the blank shown can be increased to 70%.

[0115] Step 2: Heating: The round bar is heated to the forging temperature by medium frequency heating. The heating temperature is 1200±20℃, the heating power is 28%~35%, and the feeding cycle is 30 seconds.

[0116] Step 3: Roll forging: The heated round bar is roll forged to obtain a preform (e.g., Figure 14 (as shown), and clean the oxide scale off the billet after roll forging;

[0117] Step 4: Pre-forging: The pre-heated billet reaches 150-200℃, and is placed into the pre-forging cavity 3 of the forming mold for pre-forging to obtain a symmetrical pre-forged part (e.g., Figure 15 (as shown in the figure). The precast billet is positioned by the feeding trough 7, and its flow at both ends is restricted by the locking mechanism 6.

[0118] Step 5: Precision Forging: After pre-forging, the pre-forged part is transferred to the precision forging cavity 4 of the same forming die for precision forging to obtain a symmetrical precision forging part (e.g., Figure 16 (as shown); where excess material generated during precision forging flows into the diversion chamber 5;

[0119] Step 6: Trimming: Place the symmetrical precision forgings into the planing die for trimming to remove the flash. After trimming, place the product on a conveyor belt for air cooling. Turn on the fan at a speed of 50 Hz and a transmission cycle of 11.5 ± 5 minutes. The core tensile strength of the precision forgings is 400-550 MPa, and the surface hardness is 120-165 HBW 5 / 75.

[0120] Step 7: Shot blasting: Perform surface shot blasting on the precision forgings after edge trimming to remove surface oxide scale. If surface defects are found after shot blasting, such as dents, oxide scale indentations, macroscopic inclusions, or indentations, the forgings need to be ground and repaired. After grinding, shot blasting is performed. The shot blasting time for repaired parts is 10-15 minutes to ensure consistent surface quality of the forgings. Use 0.8mm diameter steel wire shot, and set the current between 18-24A, not exceeding 25A.

[0121] Step 8: Cold forming: The functional surfaces of the symmetrical precision forgings are formed at room temperature to ensure their thickness and contour accuracy;

[0122] Step 9: Cutting: Install the cold-formed symmetrical precision forgings onto the mounting fixture, and cut them from point 5 of the flow divider using a cutting device, separating them into two independent single forgings (e.g., Figure 1 (as shown)

[0123] Step 10: Clean, prevent rust, and store in the warehouse.

[0124] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A deep-cavity thin-walled support forging, characterized in that: Includes a forging body, which is integrally formed, and the forging body includes... Deep cavity (8) The shallow cavity (9) is connected to the deep cavity (8) as a whole through an arc-shaped transition section; A square side flat portion (10) is located at the end of the shallow cavity portion (9), and the square side flat portion (10) is disposed away from the deep cavity portion (8); A V-shaped notch (11) is formed at the connection between the deep cavity (8) and the shallow cavity (9). Both the deep cavity (8) and the shallow cavity (9) have local opening structures at the ends away from each other. The opening edges of the deep cavity (8) and the shallow cavity (9) are provided with outwardly extending convex edges, and the top surfaces of the deep cavity and the shallow cavity are both formed with burr bridges (12) at their opposite corners.

2. The deep cavity thin-walled support forging according to claim 1, characterized in that: The depth of the deep cavity (8) is less than or equal to 70 mm, and the wall thickness of the deep cavity is 3.7 to 4.3 mm.

3. A forging die for a deep-cavity thin-walled support forging as described in any one of claims 1 to 2, characterized in that: Includes a mold body, the mold body comprising Upper mold (1), The lower mold (2) is set opposite to the upper mold (1). After the lower mold (2) and the upper mold (1) are closed, a pre-forging cavity (3) and a precision forging cavity (4) are set side by side along the length of the mold. The layout of the pre-forging cavity (3) and the precision forging cavity (4) is a two-piece structure layout. A flow divider (5) is provided in the middle of the cavity of the precision forging cavity (4) for two pieces to accommodate excess material during precision forging; The locking structure is located on the contact surface between the upper mold (1) and the lower mold (2) and is used to position and guide the upper mold (1) and the lower mold (2) during the mold closing process to prevent the mold cavity from shifting.

4. A forging die according to claim 3, characterized in that: The depth of the deep cavity of the pre-forging cavity (3) is less than the depth of the deep cavity of the precision forging cavity (4), and the difference between the volume of the bottom of the deep cavity of the pre-forging cavity (3) and the volume of the bottom of the corresponding deep cavity of the precision forging cavity (4) is within 5%.

5. A forging die according to claim 4, characterized in that: The lower die (2) is provided with a locking mechanism (6) at the edges of the flash bridges at both ends of the pre-forging cavity (3). The locking mechanism (6) is a protruding mechanism with a width of 7-12mm and a height of 1.5-3mm, which is used to restrict the flow of the blanks at both ends and facilitate filling the die cavity.

6. A forging die according to claim 5, characterized in that: The lower die (2) has a material feeding groove (7) at the entrance of the deep cavity of the pre-forging cavity (3) to facilitate the placement of the roll forging blank into the pre-forging cavity, ensure accurate positioning, and prevent the blank from rotating.

7. A forging die according to claim 3, characterized in that: The draft angle of the pre-forging cavity (3) is 0.5° to 1° larger than that of the precision forging cavity (4), and the transition fillet of the pre-forging cavity (3) is larger than that of the precision forging cavity (4).

8. A forging die according to claim 3, characterized in that: The width of the diversion chamber (5) is 2-5 mm and the height is 3-5 mm.

9. A forging die according to claim 3, characterized in that: The locking structure includes a protruding guide portion (13) provided on the upper mold (1) and a corresponding groove portion (21) provided on the lower mold (2).

10. A forming method, employing a forging die as described in claim 6, characterized in that: The specific steps are as follows: Step 1: Material preparation: Obtain round bars of the predetermined specifications; Step 2: Heating: Induction heating of the round bar to the forging temperature; Step 3: Roll forging: The heated round bar is roll forged to obtain a preform, and the oxide scale is removed from the forged preform. Step 4: Pre-forging: The pre-formed billet is placed into the pre-forging cavity (3) of the forming mold and pre-forging is performed to obtain a pre-forged part with left and right symmetry; wherein, the pre-formed billet is positioned by the feeding groove (7) and its flow at both ends is restricted by the locking mechanism (6); Step 5: Precision forging: After the pre-forging is completed, the pre-forged part is transferred to the precision forging cavity (4) of the same forming mold for precision forging to obtain a precision forging part with left and right symmetry; wherein, the excess material generated during precision forging flows into the distribution chamber (5). Step 6: Trimming: Place the symmetrical precision forgings into the planing die for trimming to remove the flash; Step 7: Shot blasting: Perform surface shot blasting on the precision forgings after edge trimming to remove surface oxide scale; Step 8: Cold forming: The functional surfaces of the symmetrical precision forgings are formed at room temperature to ensure their thickness and contour accuracy; Step 9: Cutting: Install the cold-formed symmetrical precision forgings on the mounting fixture, and cut them from the flow divider (5) using a cutting device to separate them into two independent single forgings; Step 10: Clean, prevent rust, and store in the warehouse.

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