High-precision trimming die for full-streamline near-net-shape front axle forgings

Abstract

The present invention relates to a high-precision trimming die for fully streamlined near-net-shape front axle forgings in the field of front axle forging processing tooling. It comprises a die support seat, a die, a punch and an upper die plate; the die is mounted on the die support seat, a cooling water channel is provided inside the die, and a large-scale undulating wave-like curved surface structure is provided on the top of the die; a cooling water channel is provided inside the punch; the upper die plate is connected to the punch through a punch pad, which can drive the punch to move and cooperate with the die to trim the forgings. Beneficial effects: the integrated die support seat makes the die structure highly stable; cooling water channels are provided inside the punch and die, so that the temperature of the punch and die is low and relatively constant during operation; the shape of the die is a large-scale undulating curved surface structure, which not only improves the trimming stress state, trimming sequence and process, balances, disperses and reduces the trimming resistance, makes the trimming process smooth and stable, but also avoids the final forging from contacting the curved surface structure over a large area, which causes the die to heat up too quickly, and ensures the trimming quality and forging size to remain stable.

Description

Technical Field

[0001] The invention relates to the field of machining tooling for front axle forgings, and in particular to a high-precision trimming die for a fully streamlined near-net-shape front axle forging. Background Art

[0002] like Figure 1 As shown, the fully streamlined, near-net-shape front axle forging is forged on a fully automated line. The trimming equipment is a hydraulic press, and the forging material is non-quenched and tempered steel. Forging 100 includes a kingpin 101, a bent arm 102, a spring seat 103, and an I-section 104. This type of forging is characterized by a small tolerance band of only ±2mm for the total length of the forging. The upper and lower surfaces of the spring seat are directly hot-forged and leveled, requiring no subsequent machining. The upper plane trimming band 105 must show no magnetic marks during flaw detection, and high requirements are placed on the shape, dimensional accuracy, and commercial appearance of the forging. To meet the requirement that the trimming band covering the upper surface of the spring seat after hot-forging and leveling show no magnetic marks during flaw detection, it is necessary to ensure that there is no residual flash or burrs on the upper surface of the spring seat after trimming, and that the cut is smooth and uniform, without sudden changes in abnormal protrusions or pits, and that the trimming bright band reaches above 95%. This places extremely high demands on trimming quality.

[0003] Currently, conventional trimming dies cannot meet the dimensional accuracy and appearance requirements of the trimmed strip for this fully streamlined, near-net-shape front axle forging. In particular, the requirements for direct hot forging and leveling of the upper and lower surfaces of the spring seat without subsequent machining, such as a trimmed strip of at least 95% and no magnetic marks on the upper surface of the spring seat, cannot be met. The die support of conventional trimming dies is an assembled structure with poor overall structural stability. There are no guides or positioning devices between the punch and die, making it difficult to control the precision of the punch and die fit. During the trimming process, the die heats up rapidly, the cutting edge reaches high instantaneous temperatures, and the temperature fluctuates greatly, resulting in large fluctuations in the overall die length, unstable gaps between the punch and die, and prone to wear and cracking of the cutting edge. The die top is a flat surface with a right-angle cutting edge, resulting in high and unbalanced trimming resistance, a short and unstable trimming stroke, and a momentary load release at the end of trimming, resulting in a high impact and a high proportion of trimmed strips. Furthermore, the final forging and the die edge have a large contact area, causing the die to heat up too quickly. The above problems all result in the quality of trimming being unstable and the dimensional accuracy of forgings being unable to be guaranteed. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the object of the present invention is to provide a high-precision trimming die for a fully streamlined, near-net-shape front axle forging, which is used to solve the problems in the prior art of poor shape, dimensional accuracy and commercial appearance of the trimming strip of the forging, especially the problem that the trimming strip covering the upper surface of the forging spring seat after hot forging and leveling cannot reach more than 95% of the required trimming bright band as shown by the flaw detection without magnetic marks.

[0005] To achieve the above-mentioned and other related purposes, the present invention provides a high-precision trimming die for a fully streamlined near-net-shape front axle forging, which is characterized by comprising:

[0006] The die support seat is an integrated structure;

[0007] A die, the die being mounted on the die support and locked to the die support via fasteners, the die being provided with a die cavity for accommodating a front axle final forging and matching the shape of the front axle final forging, the die interior being provided with die cooling water channels distributed around the die cavity, and the top of the die being provided with a curved surface structure with a large amplitude undulating wave shape;

[0008] A punch, wherein a punch cooling water channel is provided inside the punch;

[0009] The upper template is connected to the punch through a punch pad and can drive the punch to move and cooperate with the die to trim the forging.

[0010] Optionally, a punch guide post is installed on the punch pad, and a die guide sleeve is installed on the die to cooperate with the punch guide post for guidance.

[0011] Optionally, the direction of the cooling water channel of the concave mold corresponds to the direction of the length direction of the concave mold cavity; the direction of the cooling water channel of the punch corresponds to the direction of the length direction of the punch.

[0012] Optionally, the male mold cooling water channel and the female mold cooling water channel both include a plurality of straight pipe sections that are cross-distributed and connected in sequence, and a port at at least one end of each straight pipe section is connected to the outside.

[0013] Optionally, the curved surface structure includes a storage portion and a cutting edge corresponding to the undulating shape, the cutting edge is distributed along the top edge contour of the concave mold cavity, the cutting edge protrudes upward and is higher than the storage portion, the cutting edge has an extension surface, and is connected to one side of the storage portion through the extension surface, and the other side of the storage portion extends along the width direction of the concave mold to the two side edges of the top of the concave mold.

[0014] Optionally, the undulating shape of the cutting edge includes multiple peak sections and trough sections, the peak section is arranged at the top of the die corresponding to the kingpin, spring seat and middle part of the I-section of the front axle final forging, the middle part of the I-section corresponding to the peak section cavity is provided with protrusions on both sides, the spring seat back I-section corresponding to the peak section is provided with protrusions at both ends, the trough section is located between the two peak sections, and the peak section and the trough section adopt a multi-section curved surface for smooth transition.

[0015] Optionally, a transition layer is built-up welded on the die, and the cutting edge is built-up welded on the transition layer; the cutting edge includes a rake face and a flank face, and the rake face and the flank face intersect to form an acute-angle cutting edge.

[0016] Optionally, the included angle between the rake face and the parting surface is a cutting edge rake angle, and the angle of the cutting edge rake angle is 2° to 7°.

[0017] Optionally, the back cutting edge includes a straight section surface and an oblique section surface, the straight section surface is arranged along the normal of the parting surface, the upper end of the straight section surface intersects with the front cutting edge surface to form the acute cutting edge, and the lower end of the straight section surface intersects with the oblique section surface; the angle between the oblique section surface and the cutting edge is the cutting edge back angle, and the angle of the cutting edge back angle is 2°~7°.

[0018] Optionally, the length of the flank surface along the normal direction of the parting surface is H, and the length of the straight section surface along the normal direction of the parting surface is 1 / 3H to 2 / 5H.

[0019] As described above, the high-precision trimming die for the fully streamlined near-net-shape front axle forging of the present invention has at least the following beneficial effects: an integrated die support seat is adopted to improve the strength, rigidity and stability of the die structure; a punch cooling water channel and a die cooling water channel are respectively provided inside the punch and die so as to introduce a cooling medium into the punch and die, so that the temperature of the punch and die is low, the temperature fluctuation is small, the temperature is relatively constant, and the shape, size and gap are stable during operation; a curved surface structure with a large undulating wave shape is provided on the top of the die, which is beneficial to the stability of the trimming positioning posture , further ensuring a smooth and stable trimming process. The undulating shape of the cutting edge includes multiple wave peaks corresponding to the kingpin, spring seat, and middle I-section of the front axle final forging, as well as auxiliary support protrusions corresponding to the wave peaks in the middle of the I-section and the wave peaks on the back of the spring seat. These match the pre-set positioning and compensation bevels on the front axle final forging, adjusting the trimming sequence and progress of various parts of the front axle final forging, improving the trimming stress state, balancing, dispersing, and reducing trimming resistance. Furthermore, the cutting edge is prevented from contacting the front axle final forging with the large area of ​​the cutting edge, preventing excessive die heating and slowing down cutting edge failure. The specially structured welded cutting edge maintains high die precision and extends die life. The product requirements for the shape, dimensional accuracy and appearance of the trimmed strips of forgings are met, especially the trimmed bright strip on the upper surface of the spring seat reaches more than 95% of the trimmed strip area. There is no residual flash or burrs after trimming, and the incision is flat and uniform, without sudden changes in abnormal protrusions and pits. The trimmed strip covered after hot and warm forging and leveling shows no magnetic marks during flaw detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural diagram of the front axle forging;

[0021] Figure 2 for Figure 1 Schematic diagram of the front axle final forging's posture placement in the trimming die during the trimming process;

[0022] Figure 3for Figure 2 Schematic diagram of the structure of the middle spring seat;

[0023] Figure 4 for Figure 2 Schematic diagram of the structure of the middle kingpin;

[0024] Figure 5 A cross-sectional view of an embodiment of a high-precision trimming die for a fully streamlined near-net-shape front axle forging according to the present invention;

[0025] Figure 6 for Figure 5 Schematic diagram of the structure of the middle die support seat and the die;

[0026] Figure 7 for Figure 6 Schematic diagram of the structure of the concave die;

[0027] Figure 8 for Figure 6 Schematic diagram of the cutting edge of the die and the spring seat at the initial position of trimming;

[0028] Figure 9 for Figure 6 Schematic diagram of the cutting edge of the die and the main pin at the initial position of trimming;

[0029] Figure 10 This is a schematic diagram of the state of the cutting edge of the die and the spring seat in the traditional trimming die when they are in the initial position of trimming;

[0030] Figure 11 for Figure 5 Top view of the die;

[0031] Figure 12 for Figure 5 Main view of the punch;

[0032] Figure 13 for Figure 5 Top view of the punch;

[0033] Figure 14 This is a schematic diagram of the connection between the kingpin straight pipe section and the external water inlet and outlet pipes in one embodiment of the high-precision trimming die for a fully streamlined near-net-shape front axle forging according to the present invention;

[0034] Figure 15 for Figure 7 Schematic diagram of the local structure of the concave die;

[0035] Figure 16 for Figure 15 Cross-section view in the mid-direction AA;

[0036] Figure 17 for Figure 16 A partially enlarged schematic diagram of the cutting edge of the die.

[0037] Part Number Description

[0038] 100-forging; 101-kingpin; 1011-kingpin end face positioning slope; 1012-kingpin end face compensation slope; 102-bend arm; 103-spring seat; 1031-upper surface; 1032-spring seat upper surface positioning slope; 1033-spring seat upper surface compensation slope; 1034-spring seat back I-shaped boss positioning slope; 1035-spring seat back I-shaped boss compensation slope; 104 - I-shaped part; 105-upper surface trimming strip; 106-flash; 1061-lower die surface of flash; 200-die support seat; 201-positioning step surface; 202-forging drop channel; 203-lower limit block; 300-die; 301-die cavity; 3011-spring seat cavity surface; 302-die cooling water channel; 303-die guide sleeve; 304-transition layer; 305-cutting edge; 3 051-front cutting edge; 3052-flank cutting edge; 3052a-straight section; 3052b-oblique section; 3053-acute cutting edge; 3054-peak section; 3055-trough section; 3056-protrusion; 306-arc welding groove; 307-slot; 400-punch; 401-punch cooling water channel; 500-upper template; 501-upper limit block; 600-punch pad; 601 -Punch guide pin; 700-unloading plate; 701-unloading guide pin; 801-washer; 802-nut; 803-special waterway connector; 804-quick-change female connector; 805-quick-change male connector; 806-hose; 807-elbow; 901-kingpin straight pipe section; 902-bend arm straight pipe section; 903-I-beam straight pipe section; 904-first port; 905-second port; 906-third port. DETAILED DESCRIPTION

[0039] The following describes the embodiments of the present invention through specific examples. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments, and the details in this specification may be modified or altered based on different viewpoints and applications without departing from the spirit of the present invention.

[0040] It should be noted that the diagrams provided in the present embodiment are only schematic illustrations of the basic concept of the present invention. The diagrams only show the components related to the present invention and are not drawn according to the number, shape and size of the components during actual implementation. The type, quantity and ratio of each component during actual implementation can be changed at will, and the component layout type may also be more complex. The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the content disclosed in the specification for people familiar with this technology to understand and read. They are not used to limit the limiting conditions for the implementation of the present invention. Therefore, they have no technical significance. Any modification of the structure, change of the proportional relationship or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the efficacy and purpose of the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description and are not used to limit the scope of the implementation of the present invention. Changes or adjustments in their relative relationships should also be considered as the scope of the implementation of the present invention without substantially changing the technical content.

[0041] Before describing the embodiments of the present invention in detail, the application environment of the present invention will be described. It is understood that the forging process of the front axle forging includes a final forging process, a trimming process, and a correction process, which are performed in sequence. The forging obtained in the final forging process is generally referred to as the front axle final forging. The technology of the present invention is mainly applied to the trimming process of the fully streamlined near-net-shape front axle forging during the trimming process, and the trimming equipment is a hydraulic press. Taking into account factors such as the structure of the final forging, the trimming requirements of special parts, and the installation position of the trimming die on the press during the final forging process, by improving the overall trimming die structure strength and rigidity, the shape and trimming sequence of the die, the die temperature, and the die edge structure, etc., the quality of the trimming of special parts and the continuous stability of the forging size are ensured. After the front axle final forging is trimmed, the upper surface of the spring seat is leveled through hot and warm forging and can meet the assembly and use requirements without further machining.

[0042] See also Figures 1 to 13In one embodiment, the present application provides a high-precision trimming die for a fully streamlined, near-net-shape front axle forging, comprising a die support 200, a die 300, a punch 400, and an upper die plate 500. The die support 200 can be a one-piece structure, with the die 300 mounted on the die support 200 and locked to the die support 200 via fasteners. The die 300 is provided with a die cavity 301 for accommodating the front axle final forging and matching its shape. The die 300 is internally provided with die cooling channels 302 distributed around the die cavity 301. The top of the die 300 is provided with a large, undulating, wavy curved surface structure. The punch 400 is internally provided with a punch cooling channel 401. The upper die plate 500 is connected to the punch 400 via a punch backing plate 600 and is capable of driving the punch 400 to move and trim the forging 100 together with the die 300.

[0043] Optionally, the undulation range of the wavy curved surface structure with large fluctuations is between 35 mm and 85 mm, that is, the height difference between adjacent highest points and lowest points is between 35 mm and 85 mm.

[0044] Optionally, the undulations of the die curved surface structure are along the cutting edge direction, and the direction thereof corresponds to the length direction of the front axle forging, that is, the wavy direction corresponds to the length direction of the front axle forging.

[0045] The high-precision trimming die for the fully streamlined, near-net-shape front axle forging employs an integrated die support to enhance the stability of the die structure. By providing die cooling channels within the die and punch cooling channels within the punch, cooling media can be introduced into the die, resulting in low mold temperature, minimal temperature fluctuations, and a relatively constant temperature. This results in more stable shape, size, and clearance, ensuring the continued stability of the forging's size, shape accuracy, and trimming quality. Furthermore, a significantly undulating, wavy curved surface structure is incorporated into the die's top, facilitating the stabilization of the trimming positioning posture and further ensuring a smooth and stable trimming process. This structure adjusts the trimming sequence and progress of various parts of the front axle final forging, improves the trimming stress state, balances, disperses, and reduces trimming resistance, and avoids large-area contact between the front axle final forging and the cutting edge. This prevents excessive die heating and mitigates cutting edge failure, further ensuring the trimming quality of special parts of the forging, the forging's dimensional accuracy, and the commercial appearance of the trimming strip.

[0046] See also Figure 5 and Figure 6In one embodiment, the die support base 200 is provided with a positioning step surface 201. The die 300 is placed on the positioning step surface 201 and is locked to the die support base 200 via fasteners. The die support base adopts a one-piece structure, eliminating the need for assembly and connection, and the overall mold structure has excellent strength, rigidity, and stability. By improving the support and fastening method between the die and the die support base, the structural strength and rigidity of the die are also improved, reducing warping and deflection of the mold during operation, improving the stability of the mold structure, and ensuring consistent trimming quality.

[0047] Optionally, the fasteners include positioning keys and screws. The die 300 can be first positioned with the die support seat 200 by the positioning keys, and then fastened to the die support seat 200 by multiple rows of screws arranged according to the structure of the front axle forging.

[0048] Optionally, the positioning step surface 201 is provided with a forging drop channel 202 located directly below the die cavity. The contour of the forging drop channel 202 matches or is slightly larger than the outer contour of the forging. This not only facilitates the smooth ejection of the forging from the forging drop channel after trimming, but also ensures the stability, strength, and rigidity of the die support seat. Furthermore, the die support seat 200 may be L-shaped, with the positioning step surface 201 arranged horizontally.

[0049] See also Figures 1 to 4 、 Figures 7 to 10 The curved surface structure includes a trough portion 307 corresponding to the undulating shape and a cutting edge 305. The cutting edge 305 is distributed along the top edge contour of the concave mold cavity and protrudes upwardly above the trough portion 307. That is, the undulating shape of the cutting edge 305 is parallel to the undulating shape of the trough portion 307, but the top of the cutting edge 305 is located at a higher height than the top of the trough portion 307. The cutting edge 305 has an extended surface and is connected to one side of the trough portion 307 through the extended surface. The other side of the trough portion 307 extends along the width direction of the concave mold to the two side edges of the top of the concave mold.

[0050] Optionally, the undulating shape of the cutting edge 305 includes multiple peak sections 3054 and multiple trough sections 3055. The peak section 3054 is arranged at the top of the die corresponding to the main pin 101, the spring seat 103 and the middle part of the I-section 104 of the front axle final forging. Protrusions 3056 are provided on both sides of the cavity corresponding to the peak section in the middle of the I-section. Protrusions 3056 are provided at both ends of the I-section corresponding to the peak section on the back of the spring seat. The protrusions 3056 are used for auxiliary support. The trough section 3055 is located between the two peak sections 3054, and the peak section 3054 and the trough section 3055 are smoothly transitioned through multiple curved surfaces. The multiple wave peaks of the cutting edge form the initial horizontal positioning section when trimming the front axle final forging, so that the front axle final forging is in a horizontal position for trimming, and the kingpin, spring seat and middle of the I-beam of the front axle final forging are used as the starting points for trimming. The overall shearing state is progressive cross-shearing, that is, extending from the wave peak section to the periphery to the wave trough section, so that the starting position of trimming is dispersed. Among them, the peak section of the die surface structure corresponding to the kingpin and the peak section corresponding to the spring seat have both positioning and balancing functions. The peak section corresponding to the I-section mainly has a balancing function. The cooperation of each peak section ensures the balance of trimming resistance, improves the trimming stress state, trimming sequence and process, disperses and reduces the trimming resistance, makes the trimming process smooth and stable, and at the same time increases the trimming stroke, so that the trimming bright band on the upper surface of the spring seat is formed in the smooth and stable trimming stroke section, improves the trimming quality, and especially ensures that the proportion of the trimming bright band on the upper surface of the spring seat is increased to meet the requirement of more than 95%; the curved surface structure with large undulating waves can also avoid direct and large-area contact between the front axle final forging and the cutting edge, prevent the trimming die from heating up too quickly, slow down the failure of the cutting edge, and extend the service life.

[0051] See also Figures 1 to 4 、 Figures 7 to 10 In one embodiment, the front axle forging obtained in the final forging process has a flash 106 on the front axle forging, and the flash 106 is trimmed by the trimming die of the present application in the trimming process.

[0052] Optionally, the front axle final forging is provided with positioning and compensating surfaces for trimming positioning at the corresponding peak sections of the curved surface structure. Specifically, the positioning surfaces include a spring seat upper surface positioning surface 1032 provided in the lower die for the spring seat upper surface, a spring seat back I-section boss positioning surface 1034 provided in the lower die for the spring seat back I-section, and kingpin end face positioning surfaces 1011 provided in the lower dies for the kingpin end faces. The compensating surfaces include a spring seat upper surface compensating surface 1033 provided in the upper die for the spring seat upper surface, a spring seat back I-section boss compensating surface 1035 provided in the upper die for the spring seat back I-section, and kingpin end face compensating surfaces 1012 provided in the dies for the kingpin end faces. In this embodiment, the cutting edges of the multiple wave peaks contact and position the front axle final forging's process compensation positioning bevel to form the primary trimming positioning. The protrusions 3056 on both sides of the cavity corresponding to the wave peaks in the middle of the I-section and the protrusions 3056 on both ends of the wave peaks on the spring seat back I-section contact and form auxiliary positioning with their corresponding flash lower die surfaces. This changes the positioning method of the front axle final forging in the traditional trimming process, allowing the lower die surface 1061 of the front axle final forging's flash corresponding to the wave peaks to be suspended, while ensuring that the front axle final forging is placed horizontally on the die, improving the trimming positioning accuracy and stabilizing the trimming positioning posture of the front axle final forging, providing a foundation for a smooth and stable trimming process. Furthermore, the distance H between the flash lower die surface 1061 and the die cutting edge at the upper surface of the spring is approximately 10 mm.

[0053] Optionally, the cutting edges of the wave-shaped sections corresponding to the kingpin and spring seat areas can be used in conjunction with the positioning bevels and compensating bevels of the front axle final forging to perform trimming. The trimming order for the spring seat upper surface, the spring seat back I-shaped section, and the kingpin end faces is the positioning bevel, then the flash, then the compensating bevel. The trimming sequence and progression is such that the cutting edges of multiple wave-shaped sections simultaneously contact the positioning bevels used for process compensation in the front axle final forging, and the protrusions simultaneously contact the flash die surfaces of their corresponding sections. Trimming begins with the spring seat upper surface first, followed by the spring seat back I-shaped section and the kingpin end faces, and finally the remaining sections, until all trimming steps are complete. Adjusting the trimming sequence and progression of various front axle final forging sections balances trimming resistance, ensuring a smooth and stable trimming process and improving trimming quality. In particular, ensuring that the trimming process for the spring seat upper surface occurs within a smooth and stable stroke, resulting in a trimmed strip with the desired bright band ratio, can significantly increase the proportion of bright band within the trimmed strip.

[0054] See also Figure 5 In one embodiment, the punch 400 is connected to the upper mold plate 500 via a punch backing plate 600. A punch guide post 601 is mounted on the punch backing plate 600, and a die guide sleeve 303 is mounted on the die 300, which cooperates with the punch guide post 601 for guidance. The punch guide post and the die guide sleeve cooperate to guide and position the punch and die, improving the mold fit accuracy and maintaining a stable mold gap.

[0055] Optionally, the punch 400 is first positioned with the punch pad 600 by a positioning pin, and then fastened to the punch pad 600 by screws. The punch pad 600 is first positioned with the upper template 500 by a positioning key, and then fastened to the upper template 500 by screws.

[0056] See also Figure 5 In one embodiment, the high-precision trimming die for a fully streamlined, near-net-shape front axle forging further includes a stripper plate 700, which is located between the punch backing plate 600 and the die 300 and connected to the punch backing plate 600 via a stripper guide pin 701. The punch guide pin 601 extends through the stripper plate 700 and into the die guide sleeve 303. The punch 400 passes through the stripper plate 700 and cooperates with the die 300 for trimming. After trimming is completed, the material is discharged through the stripper plate.

[0057] See also Figure 5 In one embodiment, an upper limit block 501 is provided on the upper mold plate 500, and a lower limit block 203 is provided on the die support seat 200 to cooperate with the upper limit block 501. The upper limit block 501 and the lower limit block 203 cooperate to limit the punch and die working stroke stability.

[0058] Optionally, the lower limit block 203 is set on the positioning step surface 201 and extends and protrudes toward the upper template 500, and the upper limit block 501 is set on the side of the upper template facing the positioning step surface and extends and protrudes toward the positioning step surface.

[0059] See also Figure 1 、 Figure 6 and Figure 11 In one embodiment, the direction of the die cooling water channel 302 corresponds to the direction of the length direction of the die cavity 301, that is, the die cooling water channel 302 extends from one end of the die cavity 301 to the other end of the die cavity.

[0060] See also Figure 1 、 Figure 12 and Figure 13 In one embodiment, the direction of the punch cooling water channel 401 corresponds to the direction of the length direction of the punch 400 , that is, the punch cooling water channel 401 extends from one end of the punch 400 to the other end of the punch 400 .

[0061] See also Figures 1 to 11 In one embodiment, the concave mold cavity 301 includes a spring seat cavity surface 3011 corresponding to the spring seat 103 of the front axle forging. The spring seat cavity surface 3011 is arranged in the vertical direction. That is, when the front axle final forging is placed in the concave mold cavity, the axis of the forging kingpin is in the same direction as the horizontal direction. The forging is placed in a horizontal position in the concave mold cavity for trimming processing, which is conducive to ensuring processing quality.

[0062] Optionally, the number of die cooling water channels 302 is two or a multiple of two, that is, at least one die cooling water channel group is provided in the die, each die cooling water channel group includes two die cooling water channels, and the die cooling water channels 302 are evenly distributed on the side of the die 300 close to the spring seat cavity surface 3011 and the side of the die 300 away from the spring seat cavity surface 3011. Further, when there are two die cooling water channels, the die cooling water channels are distributed on the side of the die 300 close to the spring seat cavity surface 3011 and the side of the die 300 away from the spring seat cavity surface 3011. When there are four die cooling water channels, two die cooling water channels are arranged in layers along the vertical direction of the die on the side of the die 300 close to the spring seat cavity surface 3011, and the other two die cooling water channels are arranged in layers along the vertical direction of the die on the side of the die 300 away from the spring seat cavity surface 3011. The number of cooling water channels for the die can be set according to the size of the die and the requirements for the cooling effect, ensuring that the cooling water channels for the die are evenly distributed to ensure uniform cooling of the die.

[0063] Optionally, the die support 200 is provided with die support cooling channels for cooling the die. The die support cooling channels are also an even number and are evenly distributed on both sides of the forging drop channel. The die support cooling channels are arranged in layers along the vertical direction of the die to ensure uniform cooling.

[0064] See also Figures 1 to 13 In one embodiment, both the punch cooling channel 401 and the die cooling channel 302 comprise multiple intersecting, sequentially connected straight pipe segments, with each straight segment having a port at at least one end connected to the outside. The use of intersecting, sequentially connected straight pipe segments, i.e., interconnected by cross-drilling, allows the punch and die cooling channels to follow the contours of the punch and die cavity, respectively, ensuring effective cooling and reducing processing complexity.

[0065] Optionally, the punch cooling water channel 401 and the die cooling water channel 302 both include an I-shaped straight pipe section 903, a bent arm straight pipe section 902, and a kingpin straight pipe section group. The I-shaped straight pipe section 903 corresponds to the spring seat and the I-shaped section of the forging, the bent arm straight pipe section 902 corresponds to the bent arm of the forging, and the kingpin straight pipe section group corresponds to the kingpin of the forging, so as to ensure the cooling effect of the concave mold cavity and each part of the punch. Among them, the two ends of the I-shaped straight pipe section 903 are connected through the bent arm straight pipe section 902 and the kingpin straight pipe section group respectively, and the ports of the bent arm straight pipe section 902 and the I-shaped straight pipe section 903 connected to the outside are installed with plugs. Some of the ports are sealed by the plugs to form a one-way circulation loop, so that the cooling medium flows along the specified path to prevent the cooling medium from leaking out at will.

[0066] Optionally, each die cooling water channel 302 and punch cooling water channel 401 includes two sets of mainpin straight pipe sections, with the ends of the I-section straight pipe sections connected to the mainpin straight pipe sections via elbow straight pipe sections. Each set of mainpin straight pipe sections includes one or two mainpin straight pipe sections 901. Furthermore, each set of mainpin straight pipe sections in the die cooling water channel 302 includes one mainpin straight pipe section 901, and each set of mainpin straight pipe sections in the punch cooling water channel 401 includes two mainpin straight pipe sections 901.

[0067] Optionally, the I-section straight pipe section 903 can be set in the horizontal direction, and the main pin straight pipe section and the bent arm straight pipe section can be set horizontally, inclined or vertically, and each can correspond to the direction of the concave mold cavity and the punch, which is beneficial to ensure the cooling effect while reducing the processing difficulty and avoiding interference. Specifically, the I-shaped straight pipe section 903 and the main pin straight pipe section 901 of the die cooling water channel 302 are both arranged in parallel along a first direction, which is the length direction of the die cavity. The bent arm straight pipe section 902 of the die cooling water channel 302 close to the spring seat cavity surface 3011 is tilted along the side close to the bent arm cavity surface, and the bent arm straight pipe section 902 of the die cooling water channel 302 away from the spring seat cavity surface 3011 is vertically connected to the I-shaped straight pipe section and the main pin straight pipe section; the I-shaped straight pipe section 903 of the punch cooling water channel 401 is arranged along the horizontal direction, and the bent arm straight pipe section 902 is tilted. One section of the main pin straight pipe section 901 in the same group of main pin straight pipe sections is vertically arranged, and the other section of the main pin straight pipe section 901 is horizontally arranged.

[0068] Optionally, the number of the punch cooling water channel 401 is at least one. Furthermore, when the number of the punch cooling water channels is two or more, they are arranged in layers along the vertical direction of the punch. Specifically, the I-shaped straight pipe section and the elbow straight pipe section can be arranged in layers, shared by the main pin straight pipe section group. To ensure the flow rate and flow rate of the cooling medium, the water channel cross-sectional area of ​​the main pin straight pipe section group is larger than the cross-sectional area of ​​the I-shaped straight pipe section and the elbow straight pipe section. For example, when the punch cooling water channel is arranged in two layers, the cross-sectional area of ​​the water channel of the main pin straight pipe section group is 2.5 times the cross-sectional area of ​​the I-beam straight pipe section or the elbow straight pipe section; when the punch cooling water channel is arranged in three layers, the cross-sectional area of ​​the water channel of the main pin straight pipe section group is 4 times the cross-sectional area of ​​the I-beam straight pipe section or the elbow straight pipe section; the pipe diameter ratio of the main pin straight pipe section group, the I-beam straight pipe section, and the elbow straight pipe section can be set according to the flow rate and flow velocity requirements of the cooling medium, and is not limited to the ratio relationship listed above, as long as the cooling effect can be guaranteed.

[0069] Optionally, the die cooling channel diameter, distance from the die cavity, and cooling medium flow rate and velocity can be determined based on the mold temperature to ensure effective cooling. By installing cooling channels within the mold, the mold temperature is kept below 60°C, temperature fluctuations are kept below 30°C, and the total mold length fluctuations are kept within 1.0mm, ensuring the overall dimensional accuracy of the forging. This also results in low instantaneous edge temperature, minimal temperature fluctuations, stable mold clearance, and extended mold life, ensuring consistent trimming quality.

[0070] See also Figure 11 One end of the main pin straight pipe section 901 in the die cooling water channel 302 serves as the water inlet or outlet end, and the other end of the main pin straight pipe section 901 is connected to the elbow straight pipe section 902; one end of the elbow straight pipe section is sealed by a plug, that is, the first port 904 of the elbow straight pipe section is installed with a plug, and the other end of the elbow straight pipe section is connected to the I-section straight pipe section; both ends of the I-section straight pipe section are sealed by plugs, that is, the second port 905 of the I-section straight pipe section is installed with a plug. Among them, the spring straight pipe section of the die cooling water channel near the spring seat cavity surface 3011 passes through the corresponding part of the die cavity and the elbow of the forging, and the plug is blocked at the port of the section where the I-section straight pipe section and the elbow straight pipe section are connected to prevent the cooling medium from leaking into the die cavity.

[0071] See also Figures 1 to 14 In one embodiment, the main pin pipe segment group of the punch cooling water channel 401 includes two main pin straight pipe segments 901. The first end of one of the main pin straight pipe segments 901 in the same main pin straight pipe segment group serves as the water inlet or outlet end, connected to the water channel connector assembly. This main pin straight pipe segment 901 can be arranged horizontally, and the second end of this main pin straight pipe segment 901 is connected to the elbow straight pipe segment 902 through the other main pin straight pipe segment 901. The other main pin straight pipe segment can be arranged vertically, and the upper end of the other main pin straight pipe segment 901 that is connected to the outside is sealed with a plug, that is, the third end 906 of the other main pin straight pipe segment 901 is installed with a plug. One end of the elbow straight pipe segment is sealed with a plug, that is, the first end 904 of the elbow straight pipe segment is installed with a plug, and the other end of the elbow straight pipe segment is connected to the I-shaped straight pipe segment. The two ends of the I-shaped straight pipe segment are sealed with plugs, that is, the second end 905 of the I-shaped straight pipe segment is installed with a plug. Among them, the punch needs to enter the unloading plate and the die during operation. Each group of main pin straight pipe sections of the punch cooling water channel is provided with two main pin straight pipe sections, one of which is vertically arranged, and the other is horizontally arranged, so that the water channel joint assembly is close to the punch pad, and an avoidance groove can be plane-machined on the unloading plate, which solves the problem of interference between the water channel joint assembly of the punch and the mold.

[0072] The high-precision trimming die used for the above-mentioned fully streamlined near-net-shape front axle forging can cool the key parts of the die, effectively ensuring that the temperature of the die is low and the fluctuation range is small, so that the temperature during the trimming operation is relatively constant, and the shape, size and gap are stable, ensuring the continuous stability of the trimming quality and forging size.

[0073] See also Figure 14 The port of one of the two main pin straight pipe sections communicating with the outside is connected to the external water inlet pipe through components such as a water channel joint assembly and a quick-change joint assembly, and the port of the other main pin straight pipe section communicating with the outside is connected to the external water outlet pipe through components such as a water channel joint assembly and a quick-change joint assembly.

[0074] Optionally, the waterway connector assembly includes a dedicated waterway connector 803, a washer 801, and two nuts 802; and the quick-change connector assembly includes a quick-change female connector 804 and a quick-change male connector 805. One end of the dedicated waterway connector 803 is threadedly connected to the port of the kingpin straight pipe section and secured by the washer 801 and two nuts 802, providing excellent tightening and sealing effects. The other end of the dedicated waterway connector 803 is directly connected to the quick-change female connector 804, or the other end of the dedicated waterway connector 803 is connected to the quick-change female connector 804 via an elbow 807. Quick-change male connectors 805 are installed on one end of the hoses of the water inlet and outlet pipes, and the hoses 806 are connected to the quick-change female connector 804 via the quick-change male connector 805, making assembly and disassembly quick and convenient.

[0075] See also Figures 1 to 9 、 Figures 15 to 17 In one embodiment, a transition layer 304 is welded on the die 300, and a cutting edge 305 is welded on the transition layer. The cutting edge 305 includes a rake face 3051 and a flank face 3052. The rake face 3051 and the flank face 3052 intersect to form an acute-angle cutting edge 3053, which makes the cutting edge of the die sharper and reduces the resistance to cutting edges. The structure of the cutting edge is conducive to improving the cutting edge quality, which can not only meet the conventional cutting edge quality requirements of general forgings, but also meet the special cutting edge quality requirements of some precision forgings, and at the same time extend the service life of the mold. Among them, by welding the transition layer and the cutting edge on the die, the materials of the cutting edge and the transition layer can be selected according to needs to ensure the performance of the cutting edge. The use of layered welding is conducive to increasing the strength and high-temperature red hardness of the cutting edge, extending the service life, and ensuring the quality of cutting edges. Among them, the side of the rake face away from the cutting edge is bent and extended to form an extension surface connected to the warehouse.

[0076] Optionally, the die 300 is provided with an arc-shaped welding groove 306 connected to the transition layer 304, and the transition layer 304 is provided with an arc-shaped welding groove 306 connected to the cutting edge 305. Milling the arc-shaped welding groove 306 on the die 300 can reduce welding stress concentration, increase the contact area between the transition layer and the die, and help disperse the cutting edge load.

[0077] Optionally, the number of transition layers 304 is at least one, and the number of transition layers can be set to two or more layers as required. When the number of transition layers is greater than or equal to two, each transition layer is arranged in layers and welded together to form a whole. Using multiple transition layers allows the cladding layer to achieve a reasonable transition in structure, performance, and chemical composition, thereby improving fusion quality.

[0078] See also Figure 7 、 Figure 16 and Figure 17 In one embodiment, the die 300 can be made of medium-carbon alloy steel or hot-work die steel; the transition layer 304 can be made of an alloy welding rod, specifically CN625 from Eureka; and the cutting edge 305 can be made of a high-hardness alloy welding material, specifically a nickel-based alloy or a cobalt-based alloy. A welding material similar in quality to the die is used as the transition layer, and the die's cutting edge is then overlaid with the high-hardness alloy welding material. This multi-layer metal welding process facilitates a high-quality connection between the cutting edge and the die through the transition layer, improving the cutting edge's strength, high-temperature hardness, and wear resistance, thereby extending the life of the cutting edge.

[0079] See also Figures 1 to 7 、 Figures 15 to 17 In one embodiment, the included angle γ formed by the front cutting surface 3051 and the parting surface is the cutting edge rake angle, and the cutting edge rake angle γ can be 2°~7°.

[0080] It is understood that the parting surface of a trimming mold refers to the contact surface that is separable from the mold cavity when the product is removed from the mold. The parting surface includes one or more surfaces, which can be flat or curved. The surfaces are sequentially connected to form the parting surface. When the parting surface is perpendicular to the trimming direction of the forging (the trimming direction refers to the demolding direction of the forging. Regardless of whether it is a horizontal parting or a drop parting, the trimming direction of the forging is always vertical), it is called a horizontal parting. The parting surface of a horizontal parting can be different parallel surfaces. When the parting surface is inclined to the trimming direction of the forging, it is called a drop parting. The parting surface of a drop parting can be flat or curved. For example, some trimming molds include a horizontal parting portion and a drop parting portion. Generally, two adjacent horizontal parting portions are connected by the drop parting portion to make the parting surface continuous. However, the edge structure provided in this application can be used for both the horizontal parting portion and the drop parting portion.

[0081] Optionally, the cutting edge rake angle γ can be any value among 2°, 5°, or 7°. The specific value of γ can be selected based on the requirements. First, the strength of the die cutting edge must be ensured. Furthermore, the complexity of the forging must be considered. The higher the trimming quality requirements and the more complex the forging, the larger the angle, and vice versa.

[0082] In the above embodiment, the cutting edge is sharper by improving the design of the front angle γ of the cutting edge, and the shearing process is changed from the traditional right-angle cutting to the acute-angle cutting, which reduces the shear resistance and reduces the deformation of the forging. The initial contact between the flash of the forging and the die is changed from surface contact to line contact, and the contact area is reduced, thereby avoiding the local temperature rise of the cutting edge too fast and causing softening.

[0083] See also Figure 16 and Figure 17 In one embodiment, the back cutting edge 3052 includes a straight section surface 3052a and an oblique section surface 3052b. The straight section surface 3052a is arranged along the normal direction of the parting surface and along the direction perpendicular to the parting surface. The upper end of the straight section surface 3052a intersects with the front cutting edge 3051 to form an acute cutting edge 3053, and the lower end of the straight section surface 3052a intersects with the oblique section surface 3052b.

[0084] Optionally, the length of the flank surface 3052 along the normal direction of the parting surface is H, and the length of the straight section surface along the normal direction of the parting surface is 1 / 3H to 2 / 5H. For example, it can be any value among 1 / 3H, 11 / 30H, or 2 / 5H.

[0085] Optionally, the length H of the flank surface 3052 along the normal direction of the parting surface may be 5 mm to 8 mm, for example, any value among 5 mm, 6 mm, or 8 mm.

[0086] In the above embodiment, the segmented design of the flank reduces the shear contact area while maintaining cutting edge strength, reducing friction between the flank and the workpiece and preventing the formation of an inverted taper. This cutting edge structure significantly improves the shape, dimensional accuracy, and continuous stability, significantly increasing the proportion of the bright band on the trimmed edge, achieving consistent trimming quality, and extending the life of the die.

[0087] See also Figure 16 and Figure 17 In one embodiment, the angle α formed between the inclined surface 3052b and the trimming edge is the cutting edge clearance angle. The cutting edge clearance angle α can be between 2° and 7°. Furthermore, the cutting edge clearance angle α can be any value between 2°, 4°, or 7°. The specific value of α can be selected based on requirements, primarily to ensure the strength of the die cutting edge and then to consider the complexity of the forging. When the trimming quality requirements are higher and the forging is more complex, the angle should be larger, and vice versa.

[0088] This application describes a high-precision trimming die for fully streamlined, near-net-shape front axle forgings. The trimming equipment is a hydraulic press. Considering factors such as the final forging structure, trimming requirements for specific areas, and the trimming die's installation position on the press during the final forging process, the overall trimming die strength and rigidity, die shape and trimming sequence, die temperature, and die edge structure are improved. An integrated die support base enhances the strength, rigidity, and stability of the mold structure. Punch and die cooling water channels are installed inside the punch and die, respectively, to introduce cooling medium into the die. This ensures low temperatures, minimal temperature fluctuations, and relatively constant temperature during operation, while maintaining stable shape, size, and clearance. In particular, the die top features a sharply undulating, wavy surface. The undulating shape of the cutting edge includes multiple wave peaks corresponding to the kingpin, spring seat, and middle I-section of the front axle final forging, as well as auxiliary support protrusions on the middle I-section and the I-section on the back of the spring seat. This improves trimming stress, sequence, and progress, balancing, distributing, and reducing trimming resistance, ensuring stable trimming positioning and a smooth, stable trimming process. A specially constructed welded cutting edge maintains high mold precision and extends mold life. This ensures the trimming quality of specific areas, the consistent dimensional accuracy of forgings, and the commercial appearance of trimmed strips. Specifically, the goal is to ensure that the front axle final forging meets assembly and operational requirements after trimming, hot and warm forging, and leveling of the upper surface of the spring seat without further machining. The high-precision trimming die provides the necessary tooling for the fully streamlined, near-net-shape front axle forging, with direct hot and warm forging and leveling of the upper and lower surfaces of the spring seat.

[0089] Throughout this specification, references to terms such as "this embodiment," "example," and "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0090] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to be covered by the claims of the present invention.

Claims

1. A high-precision trimming die for a fully streamlined near-net-shape front axle forging, characterized in that: include: The die support seat is an integrated structure; The die is mounted on the die support seat and is locked with the die support seat by fasteners. The die is provided with a die cavity for accommodating the front axle final forging and matching the shape of the front axle final forging. The interior of the die is provided with die cooling water channels distributed around the die cavity. The top of the die is provided with a large-scale undulating wavy surface structure. The curved surface structure includes a bin portion and a cutting edge corresponding to the undulating shape. The cutting edge is distributed along the top edge contour of the die cavity. The cutting edge protrudes upward and is higher than the bin portion. The cutting edge has an extension surface and is connected to one side of the bin portion through the extension surface. The other side of the bin portion The undulating shape of the cutting edge extends along the width direction of the die to the edges on both sides of the die top. The undulating shape of the cutting edge includes multiple peak sections and trough sections. The peak section is provided at the top of the die corresponding to the kingpin, spring seat and middle part of the I-section of the front axle final forging. The middle part of the I-section is provided with protrusions on both sides of the cavity corresponding to the peak section. The two ends of the I-section on the back of the spring seat are provided with protrusions corresponding to the peak section. The trough section is located between the two peak sections. The peak section and the trough section adopt a multi-section curved surface for smooth transition. A transition layer is welded on the die, and the cutting edge is welded on the transition layer. The cutting edge includes a rake face and a flank face. The rake face and the flank face intersect to form an acute-angle cutting edge. A punch, wherein a punch cooling water channel is provided inside the punch; The upper template is connected to the punch through a punch pad and can drive the punch to move and cooperate with the die to trim the forging.

2. The high-precision trimming die for a fully streamlined near-net-shape front axle forging according to claim 1, characterized in that: A punch guide post is installed on the punch pad, and a die guide sleeve for guiding in cooperation with the punch guide post is installed on the die.

3. The high-precision trimming die for a fully streamlined near-net-shape front axle forging according to claim 1, characterized in that: The direction of the cooling water channel of the concave mold corresponds to the direction of the length direction of the concave mold cavity; the direction of the cooling water channel of the punch mold corresponds to the direction of the length direction of the punch mold.

4. The high-precision trimming die for a fully streamlined near-net-shape front axle forging according to claim 1, characterized in that: The male mold cooling water channel and the female mold cooling water channel both include a plurality of straight pipe sections that are cross-distributed and connected in sequence, and a port at at least one end of each straight pipe section is connected to the outside.

5. The high-precision trimming die for a fully streamlined near-net-shape front axle forging according to claim 1, characterized in that: The included angle between the front cutting edge and the parting surface is the cutting edge rake angle, and the angle of the cutting edge rake angle is 2° to 7°.

6. The high-precision trimming die for a fully streamlined near-net-shape front axle forging according to claim 1, characterized in that: The back cutting edge includes a straight section and an oblique section. The straight section is arranged along the normal of the parting surface. The upper end of the straight section intersects with the front cutting edge to form the acute cutting edge, and the lower end of the straight section intersects with the oblique section. The angle between the oblique section and the cutting edge is the cutting edge back angle, and the angle of the cutting edge back angle is 2° to 7°.

7. The high-precision trimming die for a fully streamlined near-net-shape front axle forging according to claim 6, characterized in that: The length of the flank surface along the normal direction of the parting surface is H, and the length of the straight section surface along the normal direction of the parting surface is 1 / 3H to 2 / 5H.

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