Flange cylinder piece pre-forging and finish-forging integrated die and forming method

Abstract

The invention discloses a flange cylinder piece pre-forging and finish-forging integrated die and a forming method, and belongs to the technical field of die forging forming. The die comprises a press rod, a side male die, an upper die body, a lower die body, a lower die core and a push rod; the side male die and the lower die are respectively positioned on the upper and lower surfaces of the upper die; the top of the side male die is provided with a first through hole, and the bottom is provided with a second through hole. The press rod can vertically pass through the first through hole and the second through hole; the push rod is slidably connected to the end face, away from the upper mold, of the lower mold and connected with the lower mold core so that the lower mold core can move in a lower mold cavity of the lower mold, an upper mold cavity of the upper mold and the second through hole. During pre-forging, both the lower mold core and the press rod forge and press the initial blank, so that the initial blank forms a finish-forged blank; after the side male die is opened, the lower die core and the press rod drive a finish forging blank to move downwards; according to the method, the production process can be simplified and the production period can be shortened on the basis of ensuring the size precision and the forming quality of forging forming.

Description

Technical Field

[0001] The invention belongs to the technical field of die forging, and in particular relates to a flange cylinder pre-forging and final forging integrated die and a forming method. Background Art

[0002] Flange cylinders are important connecting parts in engineering machinery, and have more stringent requirements on their organizational structure and material properties. With the upgrading of production equipment, flange cylinders are gradually manufactured using precision die forging technology. Precision die forging is a net forming technology. After the forging is formed, it can be put into use without or with only a small amount of finishing. Its material utilization rate and processing efficiency are much higher than traditional cutting processing.

[0003] Precision die forging can effectively preserve the streamline of metal, optimize the microstructure, and improve the mechanical properties. It fundamentally solves the quality defects of forgings caused by traditional die forging processes and has significant advantages such as high precision, high quality and low energy consumption. However, the special structure of flange cylinders, such as large flange diameter, significant difference between adjacent sections, and diverse flange positions, makes manufacturing more difficult. In actual production, forming defects such as step root folding and end flare often occur, resulting in poor forging forming quality, high forming load, short die life, and high production cost. Therefore, higher requirements are placed on the processing and manufacturing technology of flange cylinders.

[0004] At present, the production of flange cylinders or similar parts mostly adopts the traditional die forging process, using two forging equipment and two dies to complete the pre-forging and final forging respectively. The cylindrical blank is first upset into a side convex blank and then placed in the pre-forging die to complete the pre-forging, and then the pre-forging is moved to the final forging die to complete the final forging. This type of production method not only consumes energy and materials, but also has poor forging quality. Optimizing the forming process and die structure of such forgings is an effective improvement plan. For example, the patent with publication number CN116748494A discloses a casting and forging combination die, which combines the casting die and the forging die to realize the forging of the forging by casting first and then forging, so as to improve the forming quality of the forging. However, the die structure of the above patent is relatively complex, and the casting needs to be moved to the forging die after casting, resulting in a long production cycle and low dimensional accuracy of the forging. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a flange cylinder pre-forging and final forging integrated die and forming method, which can simplify the production process and shorten the production cycle while ensuring the dimensional accuracy and forming quality of the forging.

[0006] The present invention provides the following technical solutions:

[0007] In the first aspect, an integrated die for pre-forging and final forging of a flange cylinder is provided, comprising a press rod, a side punch, an upper die, a lower die, a lower mold core and a push rod; the side punch and the lower die are respectively located on the upper surface and the lower surface of the upper die; a pre-forging cavity is arranged in the side punch, and the upper mold cavity of the upper die passes through the upper die from top to bottom; a first through hole is arranged on the top of the side punch, and a second through hole is arranged on the bottom; the first through hole is communicated with the pre-forging cavity, and the second through hole is communicated with the pre-forging cavity and the upper mold cavity; the press rod can be moved along The first through hole and the second through hole pass through up and down; the push rod is slidably connected to the end face of the lower mold away from the upper mold, and the push rod is connected to the lower model core so that the lower model core can move in the lower model cavity of the lower mold, the upper model cavity of the upper mold and the second through hole; when pre-forging, the lower model core and the press rod forge the initial blank from the upper and lower sides respectively to form the final forging blank; when the side punch is opened, the lower model core and the press rod move downward to drive the final forging blank to move into the final forging cavity enclosed by the upper model cavity and the lower model cavity.

[0008] Optionally, the side punch includes a plurality of sub-molds, which are connected to the piston rod of the power cylinder; each of the sub-molds is slidably connected to the upper surface of the upper mold, and can move back and forth along the radial direction of the upper mold under the action of the power cylinder; multiple sub-molds move toward or away from the central axis of the side punch at the same time.

[0009] Optionally, a downwardly extending slider is provided on the lower surface of the side punch; a sliding groove matched with the sliding groove is provided on the upper surface of the upper mold, and the end of the sliding groove away from the central axis of the upper mold extends to the edge of the upper mold.

[0010] Optionally, the surface of the side punch close to the pre-forging cavity is provided with an arc-shaped protrusion protruding from the surface; the arc-shaped protrusion surrounds the central axis of the side punch; the arc-shaped protrusion includes a first arc portion, a straight portion and a second arc portion connected in sequence; the radii of the first arc portion and the second arc portion are equal; when the initial blank is located in the pre-forging cavity of the side punch and the side punch is in a locked state, the straight portion clamps the initial blank.

[0011] Optionally, the upper model cavity of the upper mold and the lower model cavity of the lower mold are both stepped holes; the large ends of the upper model cavity and the lower model cavity abut against each other, and the diameter of the large ends is consistent with the flange diameter of the flange cylinder to be formed.

[0012] Optionally, the longitudinal section of the lower mold core is an inverted T-shape, the diameter of the large end of the lower mold core is consistent with the outer diameter of the flange cylinder to be formed, the diameter of the small end is consistent with the diameter of the press rod, and both are equal to the preset inner diameter of the flange cylinder to be formed.

[0013] Optionally, the first through hole and the second through hole have the same diameter and the same axial size.

[0014] In a second aspect, a flange cylinder forming method is provided, based on the pre-forging and final forging integrated die described in any one of the first aspects, comprising the following steps:

[0015] The cylindrical initial blank is placed in the pre-forging cavity of the side punch, and the press rod and the lower mold core move relative to each other to forge the initial blank to complete the pre-forging and form the final forging blank;

[0016] The side punch opens, and the press rod and the lower mold core drive the final forging billet to move downward and enter the final forging cavity;

[0017] The press rod and the lower mold core move relative to each other to complete the final forging by forging the final forging billet and forming the flange cylinder;

[0018] The press rod moves upward into the upper mold, and the upper mold and the lower mold are separated to realize mold opening. After the mold is opened, the lower mold core moves upward to eject the formed flange cylinder, thereby realizing demoulding of the formed flange cylinder.

[0019] Optionally, the structural dimensions of the pre-forging cavity of the side punch are determined based on the structural parameters of the flange cylinder to be formed, specifically including:

[0020] According to the volume V of the flange cylinder to be formed 锻 , the flash volume V during forging process 边 and metal burning rate δ, to obtain the volume V of the final forging billet 坯 ;

[0021] V billet = (V 锻 +V 边 )(1+δ%)

[0022] According to the volume V of the final forging billet 坯 Determine the billet height H of the final forging billet 坯 ;

[0023]

[0024] Wherein, d is the inner through hole diameter of the flange cylinder to be formed;

[0025] According to the structural parameters of the flange cylinder to be formed, the blank height H of the final forging blank 坯 and the volume V of the final forging billet 坯 , obtaining the structural dimensions of the pre-forging cavity; the structural dimensions of the pre-forging cavity include the depth of the first through hole, the depth of the second through hole, the maximum outer diameter of the pre-forging cavity, the distance between the top of the pre-forging cavity and the arc-shaped protrusion on the inner wall of the side punch, the distance between the bottom of the pre-forging cavity and the arc-shaped protrusion on the inner wall of the side punch, and the first arc radius, the second arc radius and the height of the straight portion of the arc-shaped protrusion on the inner wall of the side punch; wherein the first arc radius and the second arc radius are equal;

[0026] The depth of the first through hole is equal to the depth of the second through hole, and is equal to the downward pressure of the press rod or the upward pressure of the lower mold core;

[0027] The maximum outer diameter of the pre-forging cavity is equal to the outer diameter D of the flange cylinder to be formed minus the reserved gap x;

[0028] The distance between the top of the pre-forging cavity and the arc-shaped protrusion on the inner wall of the side punch is equal to the distance between the bottom of the pre-forging cavity and the arc-shaped protrusion on the inner wall of the side punch, and both are the wall thickness H1 of the flange cylinder to be formed;

[0029]

[0030] The formula for solving the radius of the first arc portion or the radius of the second arc portion, the height of the straight portion of the arc-shaped protrusion, and the depth of the first through hole or the depth of the second through hole is as follows:

[0031]

[0032] Among them, R is the radius of the first arc portion or the radius of the second arc portion; H2 is the height of the straight portion of the arc-shaped protrusion, H3 is the depth of the first through hole or the depth of the second through hole, and y is the axial length of the flange cylinder to be formed.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] (1) By using the integrated die of the present invention, pre-forging and final forging can be completed in the vertical direction, thereby reducing manufacturing costs and avoiding adverse effects on the dimensional accuracy and production cycle of the forgings during the process of moving the final forging blank from the pre-forging to the final forging cavity. In addition, the additional equipment and processes required for pre-forging are reduced, thereby reducing production costs and time.

[0035] (2) The longitudinal cross-section of the final forging blank of the present invention is an hourglass-like shape that is concave in the middle, which can reduce the deformation of the metal in the final forging cavity, and keep the blank in the center of the die during the pre-forging and final forging processes, ensuring that the metal can flow evenly in all directions during the forming process, avoiding internal defects and poor metal flow caused by improper final forging deformation, such as folding, incomplete filling, instability, and misalignment, thereby improving the forming quality and dimensional accuracy of the forging.

[0036] (3) During the final forging process, the final forging blank of the present invention first changes from a concave shape to a drum shape and finally forms a flange cylinder. During the forming process, the contact time between the metal and the mold cavity is reduced, which can not only effectively reduce mold wear and improve the service life of the mold and the quality of forgings, but also simplify the production process, save production costs and time, and obtain a forming effect that is better than that of conventional processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the overall structure of the forming die when the initial blank enters the pre-forging cavity of the present invention;

[0038] Figure 2 It is a structural schematic diagram of the flange cylinder being located in the final forging cavity after the final forging blank of the present invention has completed final forging;

[0039] Figure 3 It is a schematic structural diagram of the side punch mold of the present invention;

[0040] Figure 4 It is a structural schematic diagram of the flange cylinder to be formed according to the present invention;

[0041] Figure 5 It is a schematic structural diagram of the split mold of the present invention;

[0042] Figure 6 It is a schematic diagram of the shape change of the final forging blank of the present invention during the final forging forming process;

[0043] Figure 7 It is a schematic diagram of the forming structure of the final forging blank in the pre-forging cavity of the present invention;

[0044] Figure 8 It is a schematic diagram of the side convex mold opening of the present invention;

[0045] Fig. 9 is a schematic diagram of the final forging blank of the present invention entering the final forging cavity;

[0046] Fig.10 It is a schematic diagram of the opening of the upper die and the lower die after the final forging is completed in the present invention;

[0047] Fig.11 This is a schematic diagram of the structure for solving the volume of the arc-shaped protrusion in Example 3.

[0048] Markings in the figure are: 1 is a press rod, 2 is a side punch, 21 is a split die, 22 is an arc-shaped protrusion, 221 is a first arc portion, 222 is a straight portion, 223 is a second arc portion, 3 is a power cylinder, 4 is an upper die, 5 is an initial blank, 6 is a lower model core, 7 is a lower die, 8 is a push rod, 9 is a final forging blank, and 10 is a flange cylinder. DETAILED DESCRIPTION

[0049] The present invention will now be described in further detail with reference to the accompanying drawings.

[0050] It should be noted that the terms such as "upper", "lower", "left", "right", "front", "back", etc. cited in the invention are only for the convenience of description, and are not used to limit the scope of the invention. The change or adjustment of their relative relationship should also be regarded as the scope of the invention without substantial change in the technical content. In addition, the term "comprise" and any of its variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0051] Example 1

[0052] like Figure 1-10 As shown, an integrated die for pre-forging and final forging of a flange cylinder is provided, comprising a press rod 1, a side punch 2, an upper die 4, a lower die 7, a lower mold core 6 and a push rod 8.

[0053] The side punch 2 and the lower mold 7 are respectively located on the upper surface and the lower surface of the upper mold 4, that is, the side punch 2, the upper mold 4 and the lower mold 7 are distributed up and down and abut against each other in the vertical direction.

[0054] A pre-forging cavity is provided in the side punch 2, and the side punch 2 is mainly used to form the final forging blank 9 after forging the initial blank 5; the side punch 2 can open or lock the mold in the horizontal direction, and the side punch 2 can clamp the initial blank 5 at the center position of the side punch 2, thereby ensuring that the flow, flow direction and flow rate of the metal are uniform during the pre-forging and final forging processes.

[0055] Specifically, in the present embodiment, the side punch 2 includes a plurality of split molds 21, and the split molds 21 are connected to the piston rod of the power cylinder 3; the piston rod of the power cylinder 3 corresponds to the split molds 21 one by one, and the power cylinder 3 is usually a hydraulic cylinder, and all the hydraulic cylinders are actuated so that the plurality of split molds 21 move toward or away from the central axis of the side punch 2 at the same time to achieve mold locking or mold opening; all the split molds 21 are enclosed together, and the cavity formed by them is the pre-forging cavity; when the initial blank 5 enters the pre-forging cavity, the power cylinder 3 of the side punch 2 provides a locking force to prevent the initial blank 5 from squeezing the side punch 2 to cause it to expand and affect subsequent forming.

[0056] Furthermore, each split mold 21 is slidably connected to the upper surface of the upper mold 4, and can move back and forth along the radial direction of the upper mold 4 under the action of the power cylinder 3; more specifically, the lower surface of the side punch 2 is provided with a downwardly extending slider; the upper surface of the upper mold 4 is provided with a slide groove adapted to the slider, and the end of the slide groove is away from the central axis of the upper mold 4 and extends to the edge of the upper mold 4. The slider and the slide groove are used in combination to constrain the freedom between the side punch 2 and the upper mold 4 and realize positioning and guiding functions, while providing locking force for final forging.

[0057] In this embodiment, the surface of the side punch 2 close to the pre-forging cavity is provided with an arc-shaped protrusion 22 protruding from the surface; the arc-shaped protrusion 22 surrounds the central axis of the side punch 2; the arc-shaped protrusion 22 includes a first arc portion 221, a straight portion 222 and a second arc portion 223 connected in sequence; the radii of the first arc portion 221 and the second arc portion 223 are equal; when the initial blank 5 is located in the pre-forging cavity of the side punch 2 and the side punch 2 is in a locked state, the straight portion 222 clamps the initial blank 5.

[0058] In this embodiment, a first through hole is provided on the top of the side punch 2, and a second through hole is provided on the bottom; the first through hole is communicated with the pre-forging cavity, and the second through hole is communicated with the pre-forging cavity and the upper model cavity; the press rod 1 can move up and down along the first through hole and the second through hole; the push rod 8 is slidably connected to the end surface of the lower mold 7 facing away from the upper mold 4, and the push rod 8 is connected to the lower model core 6, so that the lower model core 6 can move in the lower model cavity of the lower mold 7, the upper model cavity of the upper mold 4 and the second through hole; the press rod 1 is connected to the forming press, and the diameter of the press rod 1 is adapted to the diameter of the first through hole and the diameter of the cylindrical structure formed by the straight portion 222 of the arc-shaped protrusion 22.

[0059] The upper mold cavity of the upper mold 4 passes through the upper mold 4 from top to bottom; during pre-forging, the lower mold core 6 and the press rod 1 forge the initial blank 5 from the upper and lower sides respectively, so that the initial blank 5 forms a final forged blank 9; the shape of the initial blank 5 is a column; the driving method of the lower mold core 6 and the press rod 1 can refer to the prior art (not shown in the figure).

[0060] After the side punch 2 is opened, the lower model core 6 and the press rod 1 move downward at the same time to drive the final forging blank 9 to move into the final forging cavity enclosed by the upper model cavity and the lower model cavity for final forging. When the initial blank 5 has completely entered the upper model cavity, the power cylinder 3 provides thrust to return the side punch 2 to its position; during the final forging process, the press rod 1 and the lower model core 6 move toward each other to form the flange cylinder 10.

[0061] In this embodiment, the upper model cavity of the upper mold 4 and the lower model cavity of the lower mold 7 are both stepped hole shapes; the large end ends of the upper model cavity and the lower model cavity abut against each other, and the diameter of the large end is consistent with the diameter of the flange plate of the flange cylinder 10 to be formed, which facilitates the demolding of the flange plate after the upper mold 4 and the lower mold 7 are separated from each other.

[0062] Furthermore, in the present embodiment, the longitudinal section of the lower model core 6 is an inverted T-shape, the diameter of the large end of the lower model core 6 is consistent with the outer diameter of the flange cylinder 10 to be formed, and the diameter of the small end is consistent with the diameter of the press rod 1, and both are equal to the preset inner diameter of the flange cylinder 10 to be formed; the diameters of the first through hole and the second through hole are consistent, and the axial dimensions are also consistent; the diameters of the lower model core 6 and the press rod 1 are the same; the lower model core 6 and the press rod 1 are forged from the upper and lower directions, and the flash structure formed after the two are forged into place can be removed by cutting or other existing technologies in the subsequent processing process.

[0063] like Figure 6 As shown, Figure 6 (a) is a schematic diagram of the shape of the final forging blank 9, Figure 6 (b) is a schematic diagram of the structure in which the concave blank gradually changes into a drum shape during the final forging process. Figure 6 (c) is a schematic diagram of the structure in which the final forging blank 9 contacts the final forging cavity in the late stage of final forging; during the final forging process, the blank does not contact the final forging cavity at the beginning, which greatly shortens the contact time between the blank and the mold cavity, thereby reducing the wear of the final forging cavity and increasing the service life of the upper mold 4 and the lower mold 7.

[0064] It is worth noting that both the mold and forging design need to be chamfered to avoid stress concentration during the forming process that affects the service life of the mold; both the mold and forging design need to be drafted to facilitate demolding. The specific methods can refer to the existing technology.

[0065] Example 2

[0066] like Figure 7-10 As shown, a flange cylinder forming method is provided, based on the pre-forging and final forging integrated die of Example 1, comprising the following steps:

[0067] S1: The cylindrical initial blank 5 is placed into the pre-forging cavity of the side punch 2, and the press rod 1 and the lower mold core 6 move relative to each other to forge the initial blank 5 to complete the pre-forging and form the final forging blank 9.

[0068] The structure of the final forging blank 9 is an hourglass-like shape with a concave middle portion. During the pre-forging process, the downward pressing amount of the press rod 1 is consistent with the upward pressing amount of the lower mold core 6 .

[0069] S2: The side punch 2 opens, and the press rod 1 and the lower mold core 6 drive the final forging blank 9 to move downward and enter the final forging cavity.

[0070] The side punch 2 is opened under the action of the power cylinder 3. When the mold is opened, the split mold 21 slides along the upper end surface of the upper mold 4, and the sliding distance can make the final forging blank 9 move downward. Specifically, the displacement L1 of the split mold 21 sliding along the slide groove>d+R, where d is the inner through hole diameter of the flange cylinder 10 to be formed, and R is the radius of the first arc portion 221 or the radius of the second arc portion 223 of the arc-shaped protrusion 22; the displacement L2 of the final forging blank 9 driven downward by the press rod 1 and the lower mold core 6>2H1+H2+H 3+ 2R, so that the final forging blank 9 completely enters the final forging cavity; wherein, H1 is the wall thickness of the flange cylinder 10 to be formed, R is the radius of the first arc portion 221 or the radius of the second arc portion 223, H2 is the height of the straight portion 222 of the arc-shaped protrusion 22, and H3 is the depth of the first through hole or the depth of the second through hole.

[0071] S3: The press rod 1 and the lower mold core 6 move relative to each other to complete the final forging by forging the final forging blank 9 and forming the flange cylinder 10.

[0072] Before starting the final forging, the side punch 2 returns to the initial position, that is, the side punch 2 is in a locked state, at which time the final forging cavity is in a closed state, and the final forging starts.

[0073] S4: the press rod 1 moves upward into the upper mold 4, and the upper mold 4 and the lower mold 7 are separated to realize mold opening. After the mold is opened, the lower mold core 6 moves upward to eject the formed flange cylinder 10, thereby realizing demolding of the formed flange cylinder 10.

[0074] Furthermore, if Figure 3 and Figure 4 As shown, the structural dimensions of the pre-forging cavity of the side punch 2 are determined based on the structural parameters of the flange cylinder 10 to be formed.

[0075] Specifically, the following steps are performed: according to the volume V of the flange cylinder 10 to be formed 锻 , the flash volume V during forging process 边 and metal burning rate δ, the volume V of the final forging blank 9 is obtained 坯 ;

[0076] V billet = (V 锻 +V 边 )(1+δ%)

[0077] According to the volume V of the final forging blank 9 坯 Determine the blank height H of the final forging blank 9 坯 ;

[0078]

[0079] Wherein, d is the inner through hole diameter of the flange cylinder 10 to be formed;

[0080] According to the structural parameters of the flange cylinder 10 to be formed, the blank height H of the final forging blank 9 坯 and the volume V of the final forging blank 9 坯 , obtain the structural dimensions of the pre-forging cavity.

[0081] The structural dimensions of the pre-forging cavity include the depth of the first through hole, the depth of the second through hole, the maximum outer diameter of the pre-forging cavity, the distance from the top of the pre-forging cavity to the arc-shaped protrusion 22 on the inner wall of the side punch 2, the distance from the bottom of the pre-forging cavity to the arc-shaped protrusion 22 on the inner wall of the side punch 2, and the radius of the first arc portion 221, the radius of the second arc portion 223 and the height of the straight portion 222 of the arc-shaped protrusion 22 on the inner wall of the side punch 2.

[0082] The radius of the first arc portion 221 and the radius of the second arc portion 223 are equal, both being R.

[0083] The depth of the first through hole is equal to the depth of the second through hole, both being H3. H3 is equal to the downward pressing amount of the press rod 1 or the upward pressing amount of the lower mold core 6. The downward pressing amount and the upward pressing amount are preset according to expert experience.

[0084] The maximum outer diameter of the pre-forging cavity is equal to the outer diameter D of the flange cylinder 10 to be formed minus the reserved gap x, and the reserved gap x is 4-6 mm. The setting of the reserved gap can ensure that the final forging blank 9 wears the upper mold cavity during the downward movement.

[0085] The distance between the top of the pre-forging cavity and the arc-shaped protrusion 22 on the inner wall of the side punch 2 is equal to the distance between the bottom of the pre-forging cavity and the arc-shaped protrusion 22 on the inner wall of the side punch 2, and both are the wall thickness H1 of the flange cylinder 10 to be formed;

[0086]

[0087] The formulas for solving the radius R of the first arc portion 221 or the radius R of the second arc portion 223, the height H2 of the straight portion 222 of the arc-shaped protrusion 22, and the depth H3 of the first through hole or the depth H3 of the second through hole are as follows:

[0088]

[0089] Wherein, y is the axial length of the flange cylinder 10 to be formed, and the value range of R is d / 2 to (Dd) / 2.

[0090] Example 3

[0091] As a specific example, the basic design parameters of the flange cylinder 10 to be formed are shown in Table 1, and the metal material is 42CrMo.

[0092] Table 1 Basic dimensions of flange cylinder forgings

[0093] d D <![CDATA[D f ]]> H h <![CDATA[H f ]]> 40 70 90 80 10 10

[0094] According to the three-dimensional design of the basic dimensions of the flange cylinder 10 to be formed, the blank volume can be approximately: V 坯 ≈240000mm 3

[0095] Calculate the required blank height H 坯 Approximately: H 坯 =190mm

[0096]

[0097] H1 is the wall thickness of the flange cylinder, 15mm; the straight part 222 is used to fix the height of the blank to H2; the maximum section outer diameter of the pre-forging cavity of the side punch 2 is the outer diameter D of the cylinder minus 4mm, and a 2mm gap is reserved on one side to prevent the preform from wearing the upper model cavity during the downward movement; the thickness of the upper end plate of the side punch 2 is H3, and the thickness of the lower end plate of the side punch 2 is equal to the thickness of the upper end plate. Since the height of the lower end is equal to the height of the upper end, the downward pressure of the forming press is equal to the upward pressure of the lower die core, and the pre-forging downward pressure of the forming press and the upward pressure of the lower die core are both H3; the first arc portion 221 and the second arc have a complementary radius R, and the value range of R is d / 2~(Dd) / 2. The coordinate system is established as follows Fig.11 As shown, by combining the billet volume and forging size, taking R = 18, we can calculate: H2, H3

[0098]

[0099]

[0100] Table 2 Design dimensions of the pre-forging cavity of the side punch 2

[0101] <![CDATA[H1]]> <![CDATA[H2]]> <![CDATA[H3]]> R 15 69.2 27.4 18

[0102] The initial state of the side punch 2 is that the top end surface of the lower model core 6 is flush with the bottom end surface of the side punch 2. The cylindrical blank is placed in the side punch 2, the side die cylinder provides locking force and presses the blank, the forming press rod moves downward by 27.4mm, and at the same time, the push rod 8 pushes the lower model core 6 to move upward by 27.4mm to complete the pre-forging of the blank; the side die cylinder pulls the side punch 2 along the trapezoidal groove to move circumferentially by L1>38mm to complete the mold opening; the forming press rod and the push rod 8 move downward by L2>162.6mm at the same time, so that the preform completely enters the final forging mold; the side die cylinder pushes the side punch 2 back to the initial position, and the final forging mold cavity is closed; the push rod 8 pushes the lower model core 6 to move upward to the predetermined position, and at the same time, the forming press rod moves downward until the flange cylinder is formed; finally, the upper mold 4 and the press rod 1 move upward to complete the mold opening, and finally the push rod 8 moves upward to push the forging out of the lower mold cavity to complete the removal.

[0103] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0104] The above are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should be regarded as the protection scope of the present invention.

Claims

1. An integrated die for pre-forging and final forging of flange cylinder, characterized in that: The invention comprises a press rod (1), a side punch (2), an upper mold (4), a lower mold (7), a lower mold core (6) and a push rod (8); the side punch (2) and the lower mold (7) are respectively located on the upper surface and the lower surface of the upper mold (4); a pre-forging cavity is arranged in the side punch (2), and the upper mold cavity of the upper mold (4) passes through the upper mold (4) from top to bottom; a first through hole is arranged at the top of the side punch (2), and a second through hole is arranged at the bottom; the first through hole is communicated with the pre-forging cavity, and the second through hole is communicated with the pre-forging cavity and the upper mold cavity; the press rod (1) can pass up and down along the first through hole and the second through hole; A push rod (8) is slidably connected to the end surface of the lower die (7) facing away from the upper die (4), and the push rod (8) is connected to the lower mold core (6) so that the lower mold core (6) can move in the lower mold cavity of the lower die (7), the upper mold cavity of the upper die (4) and the second through hole; during pre-forging, the lower mold core (6) and the press rod (1) respectively forge the initial blank (5) from the upper and lower sides so that the initial blank (5) forms a final forging blank (9); when the side punch (2) is opened, the lower mold core (6) and the press rod (1) move downward to drive the final forging blank (9) to move into the final forging cavity enclosed by the upper mold cavity and the lower mold cavity.

2. The flange cylinder pre-forging and final forging integrated die according to claim 1, characterized in that: The side punch (2) comprises a plurality of split molds (21), wherein the split molds (21) are connected to the piston rod of the power cylinder (3); each of the split molds (21) is slidably connected to the upper surface of the upper mold (4), and can move back and forth along the radial direction of the upper mold (4) under the action of the power cylinder (3); and a plurality of the split molds (21) simultaneously move toward or away from the central axis of the side punch (2).

3. The flange cylinder pre-forging and final forging integrated die according to claim 2, characterized in that: The lower surface of the side punch (2) is provided with a sliding block extending downward; the upper surface of the upper mold (4) is provided with a sliding groove matched with the sliding block, and the end of the sliding groove away from the central axis of the upper mold (4) extends to the edge of the upper mold (4).

4. The flange cylinder pre-forging and final forging integrated die according to claim 1, characterized in that: The surface of the side punch (2) close to the pre-forging cavity is provided with an arc-shaped protrusion (22) protruding from the surface; the arc-shaped protrusion (22) surrounds the central axis of the side punch (2); the arc-shaped protrusion (22) includes a first arc portion (221), a straight portion (222) and a second arc portion (223) connected in sequence; the radii of the first arc portion (221) and the second arc portion (223) are equal; when the initial blank (5) is located in the pre-forging cavity of the side punch (2) and the side punch (2) is in a clamping state, the straight portion (222) clamps the initial blank (5).

5. The flange cylinder pre-forging and final forging integrated die according to claim 1, characterized in that: The upper mold cavity of the upper mold (4) and the lower mold cavity of the lower mold (7) are both stepped holes; the large ends of the upper mold cavity and the lower mold cavity abut against each other, and the diameter of the large ends is consistent with the diameter of the flange plate of the flange cylinder (10) to be formed.

6. The flange cylinder pre-forging and final forging integrated die according to claim 5, characterized in that: The longitudinal section of the lower mold core (6) is an inverted T-shape, the diameter of the large end of the lower mold core (6) is consistent with the outer diameter of the flange cylinder (10) to be formed, and the diameter of the small end is consistent with the diameter of the press rod (1), and both are equal to the preset inner diameter of the flange cylinder (10) to be formed.

7. The flange cylinder pre-forging and final forging integrated die according to claim 1, characterized in that: The first through hole and the second through hole have the same diameter and the same axial size.

8. A flange cylinder forming method, characterized in that: The pre-forging and final forging integrated die according to any one of claims 1 to 7 comprises the following steps: A cylindrical initial blank (5) is placed in the pre-forging cavity of the side punch (2), and the press rod (1) and the lower mold core (6) move relative to each other to forge the initial blank (5) to complete the pre-forging and form a final forging blank (9); The side punch (2) opens the die, and the press rod (1) and the lower die core (6) drive the final forging blank (9) to move downward and enter the final forging cavity; The press rod (1) and the lower mold core (6) move relative to each other to complete the final forging of the final forging blank (9) and form the flange cylinder (10); The press rod (1) moves upward into the upper mold (4), and the upper mold (4) and the lower mold (7) are separated to realize mold opening. After the mold opening, the lower mold core (6) moves upward to eject the formed flange cylinder (10), thereby realizing demoulding of the formed flange cylinder (10).

9. The flange cylinder die forging method according to claim 8, characterized in that: The structural dimensions of the pre-forging cavity of the side punch (2) are determined based on the structural parameters of the flange cylinder (10) to be formed, and specifically include: According to the volume V of the flange cylinder (10) to be formed 锻 , the flash volume V during forging process 边 and metal burning loss rate δ, to obtain the volume V of the final forging billet (9); V blank = (V 锻 + V 边 )(1 + δ%) Determining a blank height H blank of the final forging blank (9) according to a volume V blank of the final forging blank (9); Wherein, d is the inner through hole diameter of the flange cylinder (10) to be formed; According to the structural parameters of the flange cylinder (10) to be formed, the blank height H blank of the final forging blank (9) and the volume V blank of the final forging blank (9), the structural dimensions of the pre-forging cavity are obtained; the structural dimensions of the pre-forging cavity include the depth of the first through hole, the depth of the second through hole, the maximum outer diameter of the pre-forging cavity, the distance between the top of the pre-forging cavity and the arc-shaped protrusion (22) on the inner wall of the side punch (2), the distance between the bottom of the pre-forging cavity and the arc-shaped protrusion (22) on the inner wall of the side punch (2), and the radius of the first arc portion (221), the radius of the second arc portion (223) and the height of the straight portion (222) of the arc-shaped protrusion (22) on the inner wall of the side punch (2); wherein the radius of the first arc portion (221) and the radius of the second arc portion (223) are equal; The depth of the first through hole is equal to the depth of the second through hole, and both are equal to the downward pressing amount of the press rod (1) or the upward pressing amount of the lower mold core (6); The maximum outer diameter of the pre-forging cavity is equal to the outer diameter D of the flange cylinder (10) to be formed minus the reserved gap x; The distance between the top of the pre-forging cavity and the arc-shaped protrusion (22) on the inner wall of the side punch (2) is equal to the distance between the bottom of the pre-forging cavity and the arc-shaped protrusion (22) on the inner wall of the side punch (2), and both are the wall thickness H1 of the flange cylinder (10) to be formed; The formula for solving the radius of the first arc portion (221) or the radius of the second arc portion (223), the height of the straight portion (222) of the arc-shaped protrusion (22), and the depth of the first through hole or the depth of the second through hole is as follows: Wherein, R is the radius of the first arc portion (221) or the radius of the second arc portion (223); H2 is the height of the straight portion (222) of the arc-shaped protrusion (22); H3 is the depth of the first through hole or the depth of the second through hole; and y is the axial length of the flange cylinder (10) to be formed.

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