Drawing die and forming method suitable for large-diameter thin-wall dish-shaped body

Abstract

The invention discloses a deep drawing die suitable for a large-diameter thin-wall dish-shaped body and a forming method. The deep drawing die comprises a male die assembly, an edge pressing assembly, a female die assembly and an ejection mechanism. The male die assembly comprises a male die, and the molded surface of the bottom end of the male die is consistent with the inner concave molded surface of the butterfly-shaped body part; an inverted-T-shaped die handle is installed in the male die, the inverted-T-shaped bottom of the die handle is installed in the male die, and the inverted-T-shaped upper portion of the die handle is located above the male die. Connecting columns are arranged on the periphery of the inverted-T-shaped upper portion of the die handle, and the axial direction of the connecting columns is parallel to the axial direction of the die handle. Fastening studs are arranged in the two symmetrical sides of the connecting column correspondingly, and each fastening stud is of a transversely-arranged double-end structure. A clamping groove matched with one end of the fastening stud is formed in the position, close to the fastening stud, of the die handle, and the other end of the fastening stud is connected with the lengthened adjusting rod in a positioning mode. The production cost is reduced, the production period is shortened, and the obtained disc-shaped body is high in inner molded surface size precision, stable in quality and excellent in consistency.

Description

Technical Field

[0001] This invention belongs to the field of metal deep drawing technology, specifically referring to a deep drawing die and forming method suitable for large-diameter, thin-walled disc-shaped bodies. Background Technology

[0002] In the field of solid rocket engine combustion chamber shell manufacturing, ultra-high strength steel is the dominant material in engine shell manufacturing. Deep drawing of large-diameter, ultra-high strength thin-walled discs has always been a technical challenge in forming. In actual production, there are two processing schemes for ultra-high strength thin-walled discs.

[0003] One approach is reverse drawing. This method uses a floating blank holder, with the punch remaining stationary while the die moves with the machine's slide. However, reverse drawing often results in problems such as localized bulging, wrinkling, and excessive thinning in the transition zone between the cylindrical section and the disc-shaped body.

[0004] Another option is to spin the forging and then machine it into a thin-walled disc shape. This option has the disadvantages of high cost, long processing time per piece, and inability to meet the schedule requirements of mass production. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention proposes a deep-drawing die and forming method suitable for large-diameter, thin-walled disc-shaped bodies. This method enables the forming of ultra-high-strength steel plate thin-walled disc-shaped bodies in a single cold-state process. The process is simple, each disc-shaped body has high dimensional accuracy, and the quality is stable and consistent, avoiding problems such as local bulging and wrinkling. Compared with the method of spinning forged blanks and then machining to obtain thin-walled large-diameter disc-shaped bodies, this method has lower costs, higher efficiency, and saves more raw materials.

[0006] To achieve the above objectives, this invention designs a deep drawing die suitable for large-diameter, thin-walled disc-shaped bodies, used for forming disc-shaped parts for engine combustion chamber housings. Its special feature is that it comprises a punch assembly, a blank holder assembly, a die assembly, and an ejection mechanism. The punch assembly includes a punch, the bottom surface of which is consistent with the concave surface of the butterfly-shaped part; a shank is installed inside the punch, the bottom of the shank is installed inside the punch, and the upper part of the shank is located above the punch. The upper part of the mold handle is provided with connecting posts around its perimeter, and the axial direction of the connecting posts is parallel to the axial direction of the mold handle; fastening studs are respectively provided on the symmetrical sides of the connecting posts, and each fastening stud is a horizontally arranged double-headed structure. The mold handle is provided with a slot that matches one end of the fastening stud near the fastening stud. The other end of the fastening stud is positioned and connected to the extension adjustment rod. By rotating the extension adjustment rod, the fastening stud is moved in the connecting column by the thread transmission until one end of the fastening stud enters the slot of the mold handle for positioning and connection. The top of the connecting column is mounted on the drawing block of the hydraulic press. The blank holder assembly includes a fixed blank holder ring disposed around the punch, and the upper end face of the fixed blank holder ring is flush with the upper end face of the punch; the upper end face of the fixed blank holder ring is provided with a blank holder slider, the blank holder slider extends to the periphery of the connecting post, and the blank holder slider is provided with a channel for housing a corresponding extended adjustment rod. The fixed pressure ring is movably connected and fixed to the pressure slider.

[0007] The upper surface of the die assembly holds the butterfly-shaped part, and the upper surface of the butterfly-shaped part is provided with a punch assembly and a pressing assembly. The butterfly-shaped part is ejected by an ejection mechanism.

[0008] Furthermore, the die assembly includes a fixed die base, and the upper end face of the die base is provided with a die ring that matches the diameter of the butterfly-shaped part; the die ring is movably connected and fixed to the die base.

[0009] Furthermore, the die ring extends outward with a second fastening plate, which is connected and fixed to the die seat by a second bolt. A second nut is provided on the second bolt, and the die ring and the die seat are fastened by tightening the second nut.

[0010] Furthermore, the ejection mechanism includes a plunger pump ejection system on a hydraulic press and an ejector rod assembly, the top end of which contacts the bottom end of the butterfly-shaped component; the top end of the ejector rod assembly is an arc surface, and the diameter of the arc surface matches the diameter of the butterfly-shaped component.

[0011] Furthermore, the bottom of the die shank is fastened to the punch by fastening screws.

[0012] Furthermore, the punch is provided with a vent hole d inside, which extends from the bottom end of the punch to the bottom of the die shank.

[0013] Furthermore, the fixed pressure ring extends outward with a first fastening plate, which is connected and fixed to the pressure block by a first bolt. A first nut is provided on the first bolt, and the fixed pressure ring and the pressure block are fastened by tightening the first nut.

[0014] Furthermore, the bottom end of the fixed pressure ring is provided with a rolling rib, and the upper end of the die ring is provided with a rolling groove, and the rolling groove corresponds to and cooperates with the rolling rib.

[0015] This invention also designs a forming method suitable for large-diameter, thin-walled disc-shaped bodies, applicable to the aforementioned deep drawing dies suitable for large-diameter, thin-walled disc-shaped bodies, characterized by including the following steps: S1) Fix the die holder to the working platform of the hydraulic press, install the die ring on the die holder, and then hoist the fixing pressure ring on the die holder; S2) Secure the punch and the die shank with fastening screws, place the connecting post around the die shank, and place the fastening stud inside the die shank; hoist the die shank and punch together onto the lower platform of the hydraulic press. S3) Start the ejector assembly to rise, lifting the bottom of the punch until the slot of the die shank is aligned with one end of the fastening stud. Use the extended adjusting rod to position and connect with the other end of the fastening stud. Rotate the fastening stud and the extended adjusting rod, relying on the threaded transmission to drive the fastening stud to move in the connecting post until one end of the fastening stud enters the slot of the die shank for positioning and connection. Finally, install the connecting post on the drawing block. S4) Place the blank holder slider on the upper end face of the punch and fasten the fixed blank holder ring to the blank holder slider. S5) Start the hydraulic press blanking slider to drive the blanking assembly upward; open the hydraulic press drawing slider to drive the punch assembly upward; lock the drawing slider and blanking slider. S6) Place the deep-drawn disc-shaped blank on the upper plane of the die ring; S7) Set the drawing force, blank holder force, and drawing stroke of the part. Start the hydraulic press drawing slide downwards, driving the punch assembly downwards, and stop when it is a set distance away from the upper surface of the blank. Then start the hydraulic press blank holder slide downwards until the lower plane of the fixed blank holder ring contacts the blank and presses the blank synchronously with the die ring. Finally, start the hydraulic press drawing slide again, driving the punch to apply pressure and move downwards into the inner wall of the die ring to cause plastic deformation of the blank, resulting in a butterfly-shaped part with the same surface as the punch.

[0016] Further, in S5), deep drawing oil is applied to the blank holder surface of the fixed blank holder; in S6), deep drawing oil is applied to the contact area between the upper surface of the blank and the lower plane of the fixed blank holder.

[0017] The advantages of this invention are: This invention is applicable to deep drawing dies for large-diameter, thin-walled disc-shaped bodies. It adopts a forward deep drawing scheme, that is, using a fixed blank holder, with the die remaining stationary while the punch moves with the deep drawing slide of the equipment. The blank holder is fixed on the blank holder slide and moves with it, enabling the forming of ultra-high strength steel plate thin-walled disc-shaped bodies in a single cold state. This avoids problems such as local bulging and wrinkling. The process is simple, and the material utilization rate is high. It not only reduces production costs but also shortens the production cycle. Compared with the machining method for disc-shaped bodies, it improves efficiency by more than 20 times. It can efficiently complete the processing and production of large batches of disc-shaped bodies, and each piece has high dimensional accuracy and stable and consistent quality. 2. This invention is applicable to the forming method of large-diameter, thin-walled disc-shaped bodies and belongs to the field of thin-walled disc-shaped body deep drawing forming technology. The obtained thin-walled disc-shaped body has a small gap between the inner surface and the template, high dimensional accuracy, and excellent matching with the spun cylinder assembly welding.

[0018] This invention relates to a deep-drawing die and forming method for large-diameter, thin-walled disc-shaped bodies. It can cold-form thin-walled disc-shaped bodies made of ultra-high-strength steel plates. The process is simple, the material utilization rate is high, which not only reduces production costs but also shortens the production cycle. The resulting thin-walled disc-shaped body has a small gap between the inner surface and the template, high dimensional accuracy, and stable and consistent quality, avoiding problems such as local bulging and wrinkling. It has a promising application prospect in the production of solid rocket engine combustion chamber shell parts in the aerospace field. Attached Figure Description

[0019] Figure 1 This is a cross-sectional structural diagram of a deep drawing die suitable for large-diameter, thin-walled disc-shaped bodies in this invention (disc-shaped part in the stretched state). Figure 2 for Figure 1 Enlarged view of the structure of the central fastening stud; Figure 3 for Figure 1 Enlarged structural diagram of the butterfly-shaped component; In the figure: punch assembly 1 (not shown), blank holder assembly 2 (not shown), die assembly 3 (not shown), ejection mechanism 4 (not shown), butterfly body component 5; The punch assembly 1 includes: punch 1-1, die shank 1-2, connecting post 1-3, fastening stud 1-4, extension adjusting rod 1-5, and fastening screw 1-6; The edge clamping assembly 2 includes: a fixed edge clamping ring 2-1, an edge clamping slider 2-2, a first fastening plate 2-3, a first bolt 2-4, and a first nut 2-5; The die assembly 3 includes: die base 3-1, die ring 3-2, second fastening plate 3-3, second bolt 3-4, second nut 3-5, and lifting screw 3-6; The ejection mechanism 4 includes: ejector rod assembly 4-1. Detailed Implementation

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] In the description of this invention, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention.

[0022] This invention can achieve one-time deep drawing of sheet metal into thin-walled large-diameter dish-shaped bodies with diameters of Φ600mm to Φ1600mm.

[0023] Example 1 A thin-walled dish-shaped body of ultra-high strength steel with dimensions of 3.3mm (thickness δ) × φ800mm (outer diameter D) × 330mm (depth h) was prepared.

[0024] like Figure 1 As shown, the present invention provides a deep drawing die suitable for large-diameter, thin-walled disc-shaped bodies, used for forming disc-shaped body parts 5 for engine combustion chamber housings, comprising a punch assembly 1, a blank holder assembly 2, a die assembly 3, and an ejection mechanism 4.

[0025] The upper surface of the die assembly 3 holds the butterfly-shaped component 5. The upper surface of the butterfly-shaped component 5 is provided with the punch assembly 1 and the pressing assembly 2, and the butterfly-shaped component 5 is ejected by the ejection mechanism 4.

[0026] The punch assembly 1 includes a punch 1-1, the bottom surface of the punch 1-1 is consistent with the concave surface of the butterfly-shaped part 5; a top-shaped mold shank 1-2 is installed inside the punch 1-1, the bottom of the top-shaped mold shank 1-2 is installed inside the punch 1-1, and the upper part of the top-shaped mold shank is located above the punch 1-1.

[0027] Preferably, the bottom of the die shank 1-2 is fastened to the punch 1-1 by fastening screws 1-6.

[0028] In this embodiment, the punch 1-1 is made of ductile iron.

[0029] Preferably, the punch 1-1 is provided with a vent hole d, which extends from the bottom end of the punch 1-1 to the bottom of the die shank 1-2, so as to facilitate the gas discharge of the butterfly-shaped part 5 during the deep drawing process and avoid the formation of a vacuum field.

[0030] Preferably, the vent d is a T-shaped vent.

[0031] The upper part of the die handle 1-2 is provided with connecting posts 1-3 around its perimeter, and the axial direction of the connecting posts 1-3 is parallel to the axial direction of the die handle 1-2. Each of the two symmetrical sides of the connecting posts 1-3 is provided with a fastening stud 1-4, each of the fastening studs 1-4 being a horizontally arranged double-headed structure, as shown in the attached figure. Figure 2 As shown.

[0032] The mold handle 1-2 is provided with a groove near the fastening stud 1-4 that matches one end of the fastening stud 1-4. The other end of the fastening stud 1-4 is positioned and connected to the extension adjustment rod 1-5. By rotating the extension adjustment rod 1-5, the fastening stud 1-4 is moved within the connecting post 1-3 by means of thread transmission until one end of the fastening stud 1-4 enters the groove of the mold handle 1-2 for positioning and connection. The fastening stud 1-4 supports the connection and fastening between the mold handle 1-2 and the connecting post 1-3.

[0033] The top of the connecting column 1-3 is installed on the drawing slide of the hydraulic press, and the up and down movement of the drawing slide drives the punch assembly 1 to move up and down.

[0034] The blank holder assembly 2 includes a fixed blank holder ring 2-1 disposed around the punch 1-1, with the upper end face of the fixed blank holder ring 2-1 flush with the upper end face of the punch 1-1. A blank holder slider 2-2 is disposed on the upper end face of the fixed blank holder ring 2-1, and the blank holder slider 2-2 extends around the connecting post 1-3. The blank holder slider 2-2 has a channel inside for housing a corresponding extended adjustment rod 1-5.

[0035] The single-sided gap between the fixed pressure ring 2-1 and the punch 1-1 is 2mm.

[0036] The fixed pressure ring 2-1 is movably connected and fixed to the pressure slider 2-2.

[0037] Preferably, the fixed pressure ring 2-1 extends outward with a first fastening pressure plate 2-3, the first fastening pressure plate 2-3 is connected and fixed to the pressure block 2-2 by a first bolt 2-4, and a first nut 2-5 is provided on the first bolt 2-4. By tightening the first nut 2-5, the fixed pressure ring 2-1 and the pressure block 2-2 are connected and fixedly connected.

[0038] The up-and-down movement of the pressure block 2-2 drives the fixed pressure ring 2-1 to move up and down.

[0039] A disc-shaped deep-drawing blank is provided between the punch assembly 1, the blank holder assembly 2, and the die assembly 3.

[0040] The die assembly 3 includes a fixed die seat 3-1, and the upper end face of the die seat 3-1 is connected to a die ring 3-2 that matches the diameter of the butterfly-shaped part 5.

[0041] Specifically, the die ring 3-2 has multiple diameters of different sizes, which are used in combination according to the different diameters of the butterfly-shaped parts 5 to ensure that the die ring 3-2 has sufficient rigidity after being installed on the die holder 3-1, so as to ensure that no wrinkles occur during the deep drawing process.

[0042] The die ring 3-2 is movably connected and fixed to the die base 3-1.

[0043] Preferably, the die ring 3-2 extends outward with a second fastening plate 3-3, the second fastening plate 3-3 is connected and fixed to the die base 3-1 by a second bolt 3-4, and a second nut 3-5 is provided on the second bolt 3-4. The die ring 3-2 and the die base 3-1 are fastened by tightening the second nut 3-5.

[0044] Specifically, the flatness difference of the fitting gap between the fixed pressure ring 2-1 and the pressure surface of the die ring 3-2 is ≤0.20mm.

[0045] Preferably, the bottom end of the fixed pressure ring 2-1 is provided with a rolling rib to prevent wrinkling of the suspended section of the disc-shaped deep drawing billet during the deep drawing process.

[0046] Preferably, the upper end of the die ring 3-2 is provided with a calendering groove, the center of which corresponds to the calendering rib on the fixed blank holder 2-1. The two work together to place the blank on the die ring 3-2 during the deep drawing process, start the blank holder slider 2-2, and the fixed blank holder 2-1 contacts the blank. As the blank holder slider 2-2 continues to move down, the calendering rib on the fixed blank holder 2-1 and the calendering groove on the die ring 3-2 press the blank down, which can effectively prevent the blank from flowing too fast and causing inconsistent deformation.

[0047] The outer side of the concave mold ring 3-2 is also provided with lifting screws 3-6 for installation and hoisting.

[0048] The ejection mechanism 4 includes a plunger pump ejection system on a hydraulic press and an ejector rod assembly 4-1. The top end of the ejector rod assembly 4-1 contacts the bottom end of the butterfly-shaped part 5. The top end of the ejector rod assembly 4-1 is an arc surface, and the diameter of the arc surface matches the diameter of the butterfly-shaped part 5. This is to ensure that no contact marks are generated during the installation of the punch 1-1 and during the demolding process after the butterfly-shaped part 5 is formed.

[0049] In this embodiment, the top rod has a diameter of Φ260mm and the arc surface has a diameter of R600.

[0050] This invention also designs a forming method suitable for large-diameter, thin-walled disc-shaped bodies, applicable to the deep drawing die for large-diameter, thin-walled disc-shaped bodies, comprising the following steps: S1)~S4) are the mold installation steps.

[0051] S1) Start the hydraulic press, move the work platform out, fix the matching diameter die holder 3-1 on the work platform, and align the center of the die holder 3-1 with the center of the hydraulic press; then install the die ring 3-2 on the die holder 3-1, and then hoist the fixed pressure ring 2-1 on the die holder 3-1, so that the centers of the die holder 3-1, the die ring 3-2, and the fixed pressure ring 2-1 are aligned with the center of the work platform.

[0052] Specifically, the die ring 3-2 is fastened to the die base 3-1 by the second fastening plate 3-3, the second bolt 3-4, and the second nut 3-5.

[0053] The die ring 3-2 remains stationary throughout the deep drawing process.

[0054] S2) Fasten the punch 1-1 and the die shank 1-2 with fastening screws 1-6, and fit the connecting post 1-3 around the top of the die shank 1-2. Place the fastening stud 1-4 inside the die shank 1-2. Use a special lifting tool to lift the die shank 1-2 and the punch 1-1 onto the lower platform of the hydraulic press, so that the center of the punch 1-1 coincides with the center of the working platform.

[0055] S3) Start the hydraulic press, return the work platform to its original position, then start the ejector cylinder plunger pump to start the ejector assembly 4-1 to rise, lift the bottom of the punch 1-1, and slowly rise until the slot of the die shank 1-2 is aligned with one end of the fastening stud 1-4. Use the extended adjusting rod 1-5 to position and connect with the other end of the fastening stud 1-4. Rotate the fastening stud 1-4 and the extended adjusting rod 1-5, and rely on the threaded transmission to drive the fastening stud 1-4 to move in the connecting column 1-3 until one end of the fastening stud 1-4 enters the slot of the die shank 1-2 for positioning and connection. Finally, install the connecting column 1-3 on the drawing slide block.

[0056] S4) Place the pressure block 2-2 on the upper end face of the punch 1-1, and fasten the fixed pressure ring 2-1 to the pressure block 2-2 through the first fastening plate 2-3, the first bolt 2-4, and the first nut 2-5, so that the pressure block 2-2 moves up and down, driving the fixed pressure ring 2-1 to move up and down.

[0057] After the entire mold is aligned, all components are then tightened into place.

[0058] After the entire mold is installed, adjust the flatness difference between the contact gap between the fixed pressure ring 2-1 and the pressure surface of the die ring 3-2 to ≤0.20mm to ensure uniform pressure force during the forming process.

[0059] S5)~S7) are the deep drawing steps for butterfly-shaped parts.

[0060] S5) Start the hydraulic press blanking slider 2-2, which drives the blanking assembly 2 to move upward; open the hydraulic press deep drawing slider, which drives the punch assembly 1 to move upward; so that the punch assembly 1, blanking assembly 2 and die assembly 3 are separated, the opening and closing gap is ≥600mm, the deep drawing slider and blanking slider 2-2 are locked, and a layer of special deep drawing oil is evenly applied to the blanking surface of the fixed blanking ring 2-1.

[0061] S6) Place the disc-shaped deep drawing blank on the upper plane of the die ring 3-2, with the center of the blank aligned and coincident with the center of the die. Apply a layer of special deep drawing oil to the contact area between the upper surface of the blank and the lower plane of the fixed pressure ring 2-1.

[0062] In this embodiment, the dish-shaped deep-drawing billet is a cold-rolled steel plate deep-drawing billet with a thickness of 3.3 mm and an outer diameter of φ1130 mm.

[0063] S7) Set the drawing force, blank holder force, and drawing stroke on the hydraulic press control panel. Start the hydraulic press drawing slide downwards, driving the punch assembly 1 downwards, and stop when it is a set distance away from the upper surface of the blank. Then start the hydraulic press blank holder slide 2-2 downwards until the lower plane of the fixed blank holder ring 2-1 contacts the blank and presses the blank synchronously with the die ring 3-2. Finally, start the hydraulic press drawing slide again, driving the punch 1-1 to press down and enter the inner wall of the die ring 3-2 to cause plastic deformation of the blank, gradually fitting it with the surface of the punch 1-1 until it is completely fitted with the surface of the punch 1-1. The punch 1-1 moves down synchronously as the deformation process proceeds until the set stroke value is reached, that is, the stroke displacement sensor sends a signal to contact the position, and holds the pressure for 2 minutes. After the pressure holding is completed, the blank holder slide 2-2 and the drawing slide return one after the other, completing the entire disc-shaped body drawing process and obtaining a disc-shaped part 5 with the same surface as the punch 1-1.

[0064] In this embodiment, the drawing force is set to 12 MPa, the blank holder force is set to 6.8 MPa, and the drawing stroke of the part is set to 330 mm. The set distance is 15 mm.

[0065] As attached Figure 3 The figure shows a schematic diagram of the structure of a large-diameter, ultra-high-strength steel thin-walled disc prepared according to the present invention. In the figure, D is the outer diameter of the disc, h is the depth of the disc, and R is the fillet.

[0066] In this embodiment, the butterfly-shaped component 5 is a thin-walled disc-shaped body made of ultra-high strength steel with dimensions of 3.3mm (thickness δ) × φ800mm (outer diameter D) × 330mm (depth h).

[0067] Example 2 A thin-walled dish-shaped body of ultra-high strength steel with dimensions of 4.3mm (thickness) × φ1200mm (outer diameter) × 420mm (depth h) was prepared.

[0068] The difference between this embodiment 2 and this example 1 is that: A forming method suitable for large-diameter, thin-walled disc-shaped bodies is designed. In step S6), the deep-drawing blank for the disc-shaped body is a cold-rolled steel sheet with a thickness of 4.3 mm and an outer diameter of φ1650 mm. In step S7), the deep-drawing force is set to 14 MPa, the blank holder force is set to 12 MPa, and the deep-drawing stroke of the part is 420 mm. The prepared disc-shaped part 5 is an ultra-high-strength steel thin-walled disc-shaped body with specifications of 4.3 mm (thickness δ) × φ1200 mm (outer diameter D) × 420 mm (depth h).

[0069] Example 3 A thin-walled dish-shaped body of ultra-high strength steel with dimensions of 4.4 mm (thickness) × φ1400 mm (outer diameter) × 480 mm (depth h) was prepared.

[0070] The difference between this embodiment 3 and this example 1 is that: A forming method suitable for large-diameter, thin-walled disc-shaped bodies is designed. In step S6), the deep-drawing blank for the disc-shaped body is a cold-rolled steel sheet with a thickness of 4.4 mm and an outer diameter of φ1950 mm. In step S7), the deep-drawing force is set to 19 MPa, the blank holder force is set to 15 MPa, and the deep-drawing stroke of the part is 480 mm. The prepared disc-shaped part 5 is an ultra-high-strength steel thin-walled disc-shaped body with specifications of 4.4 mm (thickness δ) × φ1400 mm (outer diameter D) × 480 mm (depth h).

[0071] This invention is applicable to deep drawing dies and forming methods for large-diameter, thin-walled disc-shaped bodies. It can complete the forming of ultra-high strength steel plate thin-walled disc-shaped bodies in a cold state. The process is simple and the material utilization rate is high. It not only reduces production costs but also shortens the production cycle. The resulting thin-walled disc-shaped body has a small gap between the inner surface and the template and high dimensional accuracy. It has a promising application prospect in the production of solid rocket engine combustion chamber shell parts in the aerospace field.

[0072] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A deep drawing die suitable for large-diameter, thin-walled disc-shaped bodies, used for forming disc-shaped parts (5) for engine combustion chamber housings, characterized in that: It consists of a punch assembly (1), a blank holder assembly (2), a die assembly (3), and an ejection mechanism (4); The punch assembly (1) includes a punch (1-1), the bottom surface of which is consistent with the concave surface of the butterfly-shaped part (5); a die shank (1-2) is installed inside the punch (1-1), the bottom of the die shank (1-2) is installed inside the punch (1-1), and the upper part of the die shank is located above the punch (1-1); The upper part of the mold handle (1-2) is provided with connecting posts (1-3) around its perimeter, and the axial direction of the connecting posts (1-3) is parallel to the axial direction of the mold handle (1-2); fastening studs (1-4) are respectively provided on the symmetrical sides of the connecting posts (1-3), and each fastening stud (1-4) is a horizontally arranged double-headed structure. The mold handle (1-2) is provided with a groove that matches one end of the fastening stud (1-4) near the fastening stud (1-4). The other end of the fastening stud (1-4) is positioned and connected to the extension adjustment rod (1-5). By rotating the extension adjustment rod (1-5), the fastening stud (1-4) is moved in the connecting post (1-3) by means of thread transmission until one end of the fastening stud (1-4) enters the groove of the mold handle (1-2) for positioning and connection. The top of the connecting column (1-3) is installed on the drawing block of the hydraulic press; The blank holder assembly (2) includes a fixed blank holder ring (2-1) disposed around the punch (1-1), and the upper end face of the fixed blank holder ring (2-1) is flush with the upper end face of the punch (1-1); the upper end face of the fixed blank holder ring (2-1) is provided with a blank holder slider (2-2), the blank holder slider (2-2) extends to the periphery of the connecting post (1-3), and the blank holder slider (2-2) is provided with a channel for housing a corresponding extended adjustment rod (1-5); The fixed pressure ring (2-1) and the pressure slider (2-2) are movably connected and fixed; The upper surface of the die assembly (3) holds the butterfly-shaped part (5), and the upper surface of the butterfly-shaped part (5) is provided with the punch assembly (1) and the pressing assembly (2), and the pressed butterfly-shaped part (5) is ejected by the ejection mechanism (4).

2. The deep drawing die for large-diameter, thin-walled dish-shaped bodies according to claim 1, characterized in that: The die assembly (3) includes a fixed die seat (3-1), and the upper end face of the die seat (3-1) is provided with a die ring (3-2) that matches the diameter of the butterfly-shaped part (5); the die ring (3-2) is movably connected and fixed to the die seat (3-1).

3. The deep drawing die for large-diameter, thin-walled dish-shaped bodies according to claim 2, characterized in that: The die ring (3-2) extends outward with a second fastening plate (3-3). The second fastening plate (3-3) is connected and fixed to the die base (3-1) by a second bolt (3-4). A second nut (3-5) is provided on the second bolt (3-4). The die ring (3-2) and the die base (3-1) are fastened by tightening the second nut (3-5).

4. The deep drawing die for large-diameter, thin-walled dish-shaped bodies according to claim 1, characterized in that: The ejection mechanism (4) includes a piston pump ejection system on a hydraulic press and an ejector rod assembly (4-1). The top end of the ejector rod assembly (4-1) contacts the bottom end of the butterfly-shaped component (5). The top end of the ejector rod assembly (4-1) is an arc surface, and the diameter of the arc surface matches the diameter of the butterfly-shaped component (5).

5. The deep drawing die for large-diameter, thin-walled dish-shaped bodies according to claim 1, characterized in that: The bottom of the die handle (1-2) is fastened to the punch (1-1) by fastening screws (1-6).

6. The deep drawing die for large-diameter, thin-walled dish-shaped bodies according to claim 5, characterized in that: The punch (1-1) has a vent hole d inside, which extends from the bottom end of the punch (1-1) to the bottom of the die shank (1-2).

7. The deep drawing die for large-diameter, thin-walled dish-shaped bodies according to claim 1, characterized in that: The fixed pressure ring (2-1) extends outward with a first fastening pressure plate (2-3). The first fastening pressure plate (2-3) is connected and fixed to the pressure block (2-2) by a first bolt (2-4). A first nut (2-5) is provided on the first bolt (2-4). By tightening the first nut (2-5), the fixed pressure ring (2-1) and the pressure block (2-2) are connected and fixed.

8. The deep drawing die for large-diameter, thin-walled dish-shaped bodies according to claim 7, characterized in that: The bottom end of the fixed pressure ring (2-1) is provided with a rolling rib, and the upper end of the die ring (3-2) is provided with a rolling groove, and the rolling groove corresponds to and cooperates with the rolling rib.

9. A forming method suitable for large-diameter, thin-walled disc-shaped bodies, applicable to the deep drawing die for large-diameter, thin-walled disc-shaped bodies as described in any one of claims 1 to 8, characterized in that, Includes the following steps: S1) Fix the die holder (3-1) on the working platform of the hydraulic press, install the die ring (3-2) on the die holder (3-1), and then hoist the fixing pressure ring (2-1) on the die holder (3-1); S2) Fasten the punch (1-1) and the die shank (1-2) together with fastening screws (1-6), fit the connecting post (1-3) around the top of the die shank (1-2), and place the fastening stud (1-4) inside the die shank (1-2); hoist the die shank (1-2) together with the punch (1-1) onto the lower platform of the hydraulic press; S3) Start the lifting of the ejector assembly (4-1) to lift the bottom of the punch (1-1) until the slot of the die shank (1-2) is aligned with one end of the fastening stud (1-4). Use the extended adjusting rod (1-5) to position and connect with the other end of the fastening stud (1-4). Rotate the fastening stud (1-4) and rotate the extended adjusting rod (1-5). Rely on the thread transmission to drive the fastening stud (1-4) to move in the connecting post (1-3) until one end of the fastening stud (1-4) enters the slot of the die shank (1-2) for positioning and connection. Finally, install the connecting post (1-3) on the drawing slide. S4) Place the blank holder slider (2-2) on the upper end face of the punch (1-1) and fasten the fixed blank holder ring (2-1) to the blank holder slider (2-2); S5) Start the hydraulic press blanking slider (2-2) to drive the blanking assembly (2) upward; turn on the hydraulic press drawing slider to drive the punch assembly (1) upward; lock the drawing slider and blanking slider (2-2). S6) Place the deep-drawn disc blank on the upper plane of the die ring (3-2); S7) Set the drawing force, blank holder force and drawing stroke of the part, start the hydraulic press drawing slide down and drive the punch assembly (1) down, stop when it is a set distance away from the upper surface of the blank; then start the hydraulic press blank holder slide (2-2) down until the lower plane of the fixed blank holder ring (2-1) contacts the blank and presses the blank synchronously with the die ring (3-2); finally start the hydraulic press drawing slide again and drive the punch (1-1) to press down and enter the inner wall of the die ring (3-2) to cause the blank to undergo plastic deformation, and obtain a butterfly-shaped part (5) with the same profile as the punch (1-1).

10. The forming method for large-diameter, thin-walled dish-shaped bodies according to claim 9, characterized in that, The process includes the following steps: in S5), deep drawing oil is applied to the blanking surface of the fixed blanking ring (2-1); in S6), deep drawing oil is applied to the contact area between the upper surface of the blank and the lower plane of the fixed blanking ring (2-1).

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