阅读说明：本技术 一种法兰板锻冲挤反镦复合成型的模具及方法 (Die and method for flange plate forging, impact extrusion and reverse upsetting composite forming ) 是由 赵晓光 万东海 张令 洪大军 张明桥 冉雄波 谢朝顺 于 2019-09-20 设计创作，主要内容包括：本发明提供了一种法兰板锻冲挤反镦复合成型的模具及方法,包括下模座组件、下模、上模组件,下模座组件包括下模座、第一压缩弹簧、垫环；上模组件包括压边圈、第二压缩弹簧、冲头,压边圈设置有垂直的通孔,通孔上设置有台阶孔,冲头插入通孔,冲头上设置有环形台阶,环形台阶和台阶孔下底面之间设置有第二压缩弹簧。该方法按以下步骤加工：1)制坯；2)加热；3)锻压；4)翻边；5)冲挤；6)镦锻。模具巧妙借助弹簧压缩、回复带来的作用力与反作用力,实现多种相反方向的运动,实现锻压、拉伸、翻边、冲挤、反镦等多种成形方式,保证了金属流线的完整性,具有较高的力学性能,而且结构紧凑、实用性强,还便于模具的维修和更换。(The invention provides a die and a method for flange plate forging, impact extrusion, reverse upsetting and composite forming, wherein the die comprises a lower die holder assembly, a lower die and an upper die assembly, and the lower die holder assembly comprises a lower die holder, a first compression spring and a backing ring; the upper die assembly comprises a blank holder, a second compression spring and a punch, the blank holder is provided with a vertical through hole, a step hole is formed in the through hole, the punch is inserted into the through hole, an annular step is arranged on the punch, and the second compression spring is arranged between the annular step and the lower bottom surface of the step hole. The method comprises the following steps: 1) preparing a blank; 2) heating; 3) forging and pressing; 4) flanging; 5) impact extrusion; 6) and (6) upsetting. The die ingeniously realizes the motion in multiple opposite directions by means of the acting force and the reacting force brought by spring compression and reversion, realizes multiple forming modes such as forging, stretching, flanging, impact extrusion, reverse upsetting and the like, ensures the integrity of a metal streamline, has higher mechanical property, has compact structure and strong practicability, and is convenient for the maintenance and replacement of the die.)

1. The utility model provides a flange board forges and dashes crowded anti-compound fashioned mould of upsetting which characterized in that: comprises a lower die holder component, a lower die (4) and an upper die component,

the lower die holder assembly comprises a lower die holder (1), a first compression spring (2) and a backing ring (3), wherein the lower die holder (1) is provided with an annular groove, the bottom of the annular groove is provided with the first compression spring (2), the backing ring (3) is arranged on the first compression spring (2), and the backing ring (3) is provided with a lower die (4);

the upper die assembly comprises a blank holder (6), a second compression spring (7) and a punch (8), wherein a vertical through hole (61) is formed in the center of the blank holder (6), a built-in step hole (62) is formed in the through hole, the punch (8) is inserted into the through hole (61), an annular step (81) is formed in the punch (8), the annular step (81) is limited in the step hole (62), the second compression spring (7) is arranged between the annular step (81) and the lower bottom surface of the step hole (62), and the second compression spring (7) is sleeved on the punch (8).

2. The die for flange plate forging, impact extrusion and reverse upsetting composite forming as claimed in claim 1, wherein: the size of the punch (8) is such that the upper end of the punch (8) is kept protruding out of the through hole (61) in the whole stroke range.

3. The die for flange plate forging, impact extrusion and reverse upsetting composite forming as claimed in claim 1, wherein: when the annular step (81) is in contact with the upper top surface of the step hole (62), the lower end of the punch (8) does not extend out of the through hole (61), and the lower end surface of the punch (8) is located in the through hole (61).

4. The die for flange plate forging, impact extrusion and reverse upsetting composite forming as claimed in claim 1, wherein: the lower end of the punch (8) is provided with an inclined plane (82), and a fillet is arranged at the joint of the inclined plane (82) and the lower end face of the punch (8).

5. The die for flange plate forging, impact extrusion and reverse upsetting composite forming as claimed in claim 1, wherein: the through hole (61) is a round hole or a round rectangular hole, the punch (8) is cylindrical or a round rectangular column, and the fit clearance tolerance of the through hole (61) and the punch (8) is +/-0.005 mm.

6. The die for flange plate forging, impact extrusion and reverse upsetting composite forming as claimed in claim 1, wherein: the center of the lower die holder (1) is provided with a through inner hole, the inner hole of the lower die holder (1) is circular or rectangular with round corners, and the tolerance of the fit clearance between the inner hole of the lower die holder (1) and the punch (8) is +/-0.005 mm.

7. The die for flange plate forging, impact extrusion and reverse upsetting composite forming as claimed in claim 1, wherein: lower mould (4) are ring or fillet rectangle ring, backing ring (3) are ring or fillet rectangle ring, the ring channel of die holder (1) is ring groove or fillet rectangle ring groove, the lower extreme of lower mould (4) inserts in the ring channel of die holder (1), the upper end of lower mould (4) exceeds die holder (1), and the hole upper end opening part of lower mould (4) is provided with counter bore (41), the hole of lower mould (4) is provided with the fillet with counter bore (41) end junction, counter bore (41) highly is less than the thickness of slab (5).

8. The die for flange plate forging, impact extrusion and reverse upsetting composite forming as claimed in claim 7, wherein: the counter bore (41) is circular or rectangular.

9. A flange plate forging, impact extrusion and reverse upsetting composite forming method is characterized by comprising the following steps:

s1, forging: putting the plate blank (5) into the counter bore (41), starting a hydraulic machine, fixing the lower die holder (1), moving the punch (8) downwards, forging and pressing the flange plate blank by the blank holder (6) under the action of spring elasticity until the blank holder (6) is contacted with the lower die (4), and clamping the plate blank (5) by the blank holder (6) and the lower die (4) together;

s2, flanging: the punch (8) continues to move downwards, the guide hole is gradually enlarged under the action of the punch (8) through the guide hole, and the peripheral material of the guide hole overturns towards the hole wall of the inner hole of the lower die (4) along the outer ring of the punch (8);

s3, impact extrusion: as the punch (4) continues to move downwards, the material of the plate blank (5) at the neck part of the flange begins to be stretched and thinned under the extrusion of the punch;

s4, upsetting: the punch (8) continues to move downwards, the lower die (4) moves downwards simultaneously under the action of the punch, the backing ring (3) is enabled to extrude the first compression spring (2) to move downwards, the first compression spring contacts with the lower die holder (1) after the plate is flanged, the lower die holder (1) acts on a blank in a reverse direction, reverse upsetting is achieved, a closed cavity formed among the lower die holder (1), the lower die (4), the blank holder (6) and the punch (8) is filled with metal, the die stops moving, and a flange forging piece with the size meeting the requirements is obtained.

10. The method for flange plate forging-impact-reverse-heading composite forming as claimed in claim 9, wherein the pretreatment before the plate blank (5) is put into the counterbore (41) in step S1 comprises the steps of:

s11, blank making: selecting a plate with uniform thickness, cutting the plate according to the size requirement, and processing a guide hole in the center of the blank after cutting to obtain a plate blank (5);

s12, heating: and then putting the plate blank (5) obtained in the step S11 into a heating furnace to be heated to 1150-1180 ℃.

Technical Field

The invention belongs to the technical field of forging and pressing, and particularly relates to a die and a method for flange plate forging, impact extrusion and reverse upsetting composite forming.

Background

Flanges are common mechanical connecting parts. For manufacturing the flange, a common mode is die forming, a forging blank is manufactured through working procedures such as upsetting, punching and the like, and then machining is carried out. The molding process is multiple, the material utilization rate is very low, and simultaneously, the metal streamline is cut off through the mechanical processing with large allowance, the service life and the comprehensive performance of the product are reduced, and the manufacturing period is long. The flange produced by adopting the stretch flanging technology has large round angle, irregular end surface and limited height increase, can not obtain the flange meeting the size, and hinders the popularization and the application of the plate forging technology.

The existing plate forging, punching and extruding composite forming technology has two problems, namely, the neck of the flange needs to be subjected to large-force extrusion, and the flange and a die are mutually wrapped and are difficult to separate; secondly, under the stretching and impact extrusion action of large acting force, the defects of large stretching fillet and uneven end face are easily formed.

Disclosure of Invention

In order to solve the technical problems, the invention provides a die and a method for flange plate forging, impact extrusion and reverse upsetting composite forming, which skillfully realize the movement in various opposite directions by means of acting force and reacting force caused by spring compression and return, and realize various forming modes such as forging, stretching, flanging, impact extrusion, reverse upsetting and the like.

The invention is realized by the following technical scheme.

A die for flange plate forging, impact extrusion and reverse upsetting composite forming comprises a lower die holder assembly, a lower die and an upper die assembly, wherein the lower die holder assembly comprises a lower die holder, a first compression spring and a backing ring; the upper die assembly comprises a blank holder, a second compression spring and a punch, wherein a vertical through hole is formed in the center of the blank holder, a built-in step hole is formed in the through hole, the punch is inserted into the through hole, an annular step is arranged on the punch and limited in the step hole, the second compression spring is arranged between the annular step and the lower bottom surface of the step hole, and the second compression spring is sleeved on the punch. The spring compression and recovery bring acting force and reaction force, realize the motion of multiple opposite directions, realize multiple shaping modes such as forging and pressing, drawing, turn-ups, impact extrusion, anti-heading.

The size of the punch meets the requirement that the punch is in the whole stroke range, the upper end of the punch keeps extending out of the through hole, the blank holder is reliably positioned, and the blank holder is prevented from being in direct contact with forging equipment, so that the punch cannot completely compress the second compression spring to the completely compressed state, the stroke is insufficient, and finally the situation that the plate blank cannot be completely flanged is caused. The stroke range of the punch starts from the state that the annular step is attached to the upper top surface of the step hole of the blank holder, and the punch moves downwards to extrude the first compression spring and the second compression spring to be in a fully compressed state.

When the annular step position satisfies the contact of annular step and the top surface on the step hole, the lower extreme of drift does not stretch out the through-hole, and the lower terminal surface of drift is located the through-hole, and the blank holder contacts with the slab before the drift during punching press promptly, pushes down the slab, and the slab is fixed stable when guaranteeing the drift punching press, guarantees flange forging machining precision.

The lower end of the punch is provided with an inclined plane, a fillet is arranged at the joint of the inclined plane and the lower end face of the punch, and a slab guide hole is guided to smoothly stretch and turn over the edge in the punching process.

The through-hole is round hole or fillet rectangle hole, and the drift is cylindrical or fillet rectangle post, can process cylindrical or fillet rectangle flange centre bore, and the fit clearance tolerance of through-hole and drift is 0.005mm, guarantees blank holder position accuracy, reduces and rocks, can steadily hold the slab at whole forming process.

The center of the lower die holder is provided with a through inner hole, the inner hole of the lower die holder is circular or rectangular with round corners, the tolerance of the fit clearance between the inner hole of the lower die and the punch is +/-0.005 mm, the processing precision of the forge piece is guaranteed, the inner hole of the forge piece is directly formed, and the subsequent processing procedures are omitted.

The lower mould is ring or fillet rectangle ring, can process cylindrical or fillet rectangle flange neck, the backing ring is ring or fillet rectangle ring, the ring channel of die holder is ring groove or fillet rectangle annular, the lower extreme of lower mould inserts in the ring channel of die holder, the upper end of lower mould exceeds the die holder, and the hole upper end opening part of lower mould is provided with the counter bore, the hole of lower mould is provided with the fillet with the counter bore end junction, the fillet provides the support when the slab turns-ups, provide the certain radius of buckling of slab simultaneously, guarantee the continuity of metal streamline. The height of the counter bore is smaller than the thickness of the plate blank, so that the plate blank can be stably clamped in the forming process, and the machining precision of the flange forging is guaranteed.

The counter bore is circular or rectangular, and can be used for processing a circular or rectangular flange plate.

When first compression spring elasticity satisfied drift downstream extrusion second compression spring to the complete compression state, first compression spring did not reach the complete compression state, and still has one section distance between slab and the die holder, guarantees promptly that the slab accomplishes to dash and carries out the upset again after the crowded process, avoids the condition of lou material.

In the production process, the slab is shaping again after heating, after the shaping is accomplished, because the temperature reduction produces the shrinkage, the flange forging wraps on the drift easily, simultaneously because the extrusion of reverse-heading, the flange forging can produce the bonding with the lower mould, nevertheless the shrinkage can reduce the effect that bonds with the lower mould, the drift power of unloading upwards promotes the reset, compression spring begins the extension, under the effect of spring force, impel the flange forging to the direction motion with the lower mould separation, leave behind the lower mould blank holder and push down the flange from the drift, realize the separation of flange and mould.

A method for flange plate forging, impact extrusion and reverse upsetting composite forming comprises the following steps:

s1, forging: placing the plate blank into the counter bore, starting a hydraulic press, fixing a lower die holder, enabling a punch to move downwards to extrude a second compression spring, enabling elastic force generated by compression of the second compression spring to act on a blank holder, forging and pressing the plate blank by the blank holder under the action of the elastic force of a spring until the blank holder is contacted with a lower die, and clamping the plate blank by the blank holder and the lower die together under the action of the elastic force of the spring;

s2, stretching and flanging: the punch continues to move downwards, the punch extrudes the plate blank material to move towards the periphery through the guide hole, the guide hole is bent, stretched and thinned, the guide hole is gradually enlarged under the action of the punch, and the material around the guide hole overturns towards the wall of the inner hole of the lower die along the outer ring of the punch;

s3, impact extrusion: when the thickness of the neck of the flange forging is smaller than that of the plate blank, after the plate blank is contacted with the hole wall of the inner hole of the lower die, a space smaller than the thickness of the plate blank is formed by the punch and the inner hole of the lower die, the plate blank material begins to thin under the extrusion of the punch along with the continuous downward movement of the punch, the redundant metal begins to flow downwards, and the neck of the flange becomes thin and long; when the thickness of the neck of the flange forging is larger than or equal to that of the plate blank, the material of the plate blank at the neck of the flange starts to be stretched and thinned under the extrusion of the punch;

s4, upsetting: the punch continues to move downwards, the lower die simultaneously moves downwards under the action of the punch to enable the backing ring to extrude the first compression spring to move downwards, a closed cavity formed among the lower die base, the lower die, the blank holder and the punch is smaller and smaller in height, the plate is in contact with the lower die base after being flanged, the lower die base reversely acts on the blank to realize reverse upsetting, the end face of the flanged rear end is upset and leveled, meanwhile, redundant metal is extruded to the round corner of the upper end face until the closed cavity is filled, the die stops moving, and the flange forging piece with the size meeting the requirements is obtained. The reverse upsetting can be used for upsetting the neck of the flange, and the processing requirement that the thickness of the neck of the flange forging is larger than that of the plate blank can be met.

The flange plate forging, impact extrusion and reverse upsetting composite forming method comprises the following steps of preprocessing a plate blank before being placed into a counter bore in step S1:

s11, blank making: selecting a plate with uniform thickness, cutting the plate according to the size requirement, processing a guide hole in the center of the blank after cutting, wherein the shape of the guide hole is circular or rectangular with a round angle corresponding to the shape of the inner hole of the flange, and obtaining a plate blank;

s12, heating: and then putting the plate blank obtained in the step S11 into a heating furnace to be heated to 1150-1180 ℃.

The invention has the beneficial effects that:

compared with the prior art, the invention skillfully utilizes the acting force and the reacting force brought by the compression and the recovery of the spring to realize the movement in various opposite directions, realizes various forming modes such as forging, stretching, flanging, impact extrusion, reverse upsetting and the like, ensures the integrity of a metal streamline, has higher mechanical property, only needs one power module for stamping equipment, and reduces the equipment requirement. The blank holder and the gasket are arranged, so that the mold opening cost is greatly reduced, the structure is compact, the practicability is high, and the maintenance and the replacement of the mold are convenient. The plate with the proper thickness is selected, the flange plate can be directly formed by forging and pressing according to different flange plate thicknesses, the flange neck can be directly formed by impact extrusion according to different flange neck thicknesses, machining allowance is reduced, and production cost is saved. When the punch is subjected to force unloading and reset, the flange and the die are automatically separated by means of the elastic force of the spring. The mold has wide applicability, and various flange plates, flange necks and flange inner hole shapes can be suitable.

Drawings

FIG. 1 is a schematic structural view of a die for flange plate forging-impact-extrusion reverse-upsetting composite forming of the present invention;

FIG. 2 is a schematic view of the flange stamping and flanging process of the present invention;

FIG. 3 is a schematic representation of the completion of the flange impact extrusion drawing process of the present invention;

FIG. 4 is a schematic view of the flange of the present invention as it is being formed;

FIG. 5 is a schematic view of upsetting occurring without completion of the impact extrusion process to produce blowouts.

In the figure: 1-a lower die holder, 2-a first compression spring, 3-a backing ring, 4-a lower die, 5-a plate blank, 6-a blank holder, 7-a second compression spring, 8-a punch, 41-a counter bore, 61-a through hole, 62-a step hole, 81-an annular step and 82-an inclined plane.

Detailed Description

The technical solution of the present invention is further described below, but the scope of the claimed invention is not limited to the described.

As shown in fig. 1 to 4, a die for flange plate forging, impact extrusion, reverse upsetting and composite forming comprises a lower die holder assembly, a lower die 4 and an upper die assembly, wherein the lower die holder assembly comprises a lower die holder 1, a first compression spring 2 and a backing ring 3, the lower die holder 1 is provided with an annular groove, the bottom of the annular groove is provided with the first compression spring 2, the first compression spring 2 is provided with the backing ring 3, and the backing ring 3 is provided with the lower die 4; the upper die assembly comprises a blank holder 6, a second compression spring 7 and a punch 8, a vertical through hole 61 is formed in the center of the blank holder 6, a built-in step hole 62 is formed in the through hole, the punch 8 is inserted into the through hole 61, an annular step 81 is formed in the punch 8, the annular step 81 is limited in the step hole 62, the second compression spring 7 is arranged between the annular step 81 and the lower bottom surface of the step hole 62, and the second compression spring 7 is sleeved on the punch 8. The spring compression and recovery bring acting force and reaction force, realize the motion of multiple opposite directions, realize multiple shaping modes such as forging and pressing, drawing, turn-ups, impact extrusion, anti-heading.

The size of the punch 8 meets the requirement that the punch 8 is in the whole stroke range, the upper end of the punch 8 keeps extending out of the through hole 61, the blank holder 6 is reliably positioned, and the blank holder 6 is prevented from being in direct contact with forging equipment, so that the punch 8 cannot completely compress the second compression spring 7 until the punch is in a completely compressed state, the stroke is insufficient, and the situation that the plate blank 5 cannot be completely flanged is finally caused. The stroke range of the punch 8 starts from a state where the annular step 81 is fitted to the upper top surface of the step hole 62 until the punch 8 moves downward to press both the first compression spring 2 and the second compression spring 7 to a fully compressed state.

When the position of the annular step 81 meets the condition that the annular step 81 is in top surface contact with the step hole 62, the lower end of the punch 8 does not extend out of the through hole 61, and the lower end surface of the punch 8 is located in the through hole 61, namely, the blank holder 6 is in contact with the blank 5 before the punch 8 during punching to press the blank 5, so that the blank 5 is fixed and stable during punching by the punch 8, and the processing precision of the flange forging is ensured.

The lower end of the punch 8 is provided with an inclined plane 82, a fillet is arranged at the joint of the inclined plane 82 and the lower end face of the punch 8, and a slab guide hole is guided to stretch and turn over smoothly in the punching process.

The through hole 61 is a round hole or a round rectangular hole, the punch 8 is a cylindrical or round rectangular column, a cylindrical or round rectangular flange center hole can be processed, the fit clearance tolerance of the through hole 61 and the punch 8 is +/-0.005 mm, the position precision of the blank holder is guaranteed, the shaking is reduced, and the blank 5 can be stably pressed in the whole forming process.

The center of the lower die holder 1 is provided with a through inner hole, the inner hole of the lower die holder 1 is circular or rectangular with round corners, the tolerance of the fit clearance between the inner hole of the lower die holder 1 and the punch 8 is +/-0.005 mm, the processing precision of the forge piece is guaranteed, and the inner hole of the forge piece is directly formed, so that the subsequent processing procedures are removed.

Lower mould 4 is ring or fillet rectangle ring, can process cylindrical or fillet rectangle flange neck, backing ring 3 is ring or fillet rectangle ring, the ring channel of die holder 1 is ring groove or fillet rectangle annular, the lower extreme of lower mould 4 inserts in the ring channel of die holder 1, the upper end of lower mould 4 exceeds die holder 1, and the hole upper end opening part of lower mould 4 is provided with counter bore 41, the hole of lower mould 4 is provided with the fillet with counter bore 41 end junction, the fillet provides the support when 5 turn-ups of slab, provide the certain radius of buckling of 5 slabs simultaneously, guarantee the continuity of metal flow line. The height of the counter bore 41 is smaller than the thickness of the plate blank 5, so that the plate blank 5 can be stably clamped in the forming process, and the machining precision of the flange forging is guaranteed.

The counter bore 41 is circular or rectangular and can be used for machining a circular or rectangular flange.

When the elasticity of the first compression spring 2 meets the condition that the punch 8 moves downwards to extrude the second compression spring 7 to be in a complete compression state, the first compression spring 2 does not reach the complete compression state, a distance still exists between the plate blank 5 and the lower die holder 1, namely, the plate blank 5 is guaranteed to complete the impact extrusion process and then upset, and the condition of material leakage is avoided.

As shown in fig. 5, the impact extrusion process is not completed and enters the upsetting process prematurely, causing a portion of the material of the slab 5 to be extruded, resulting in blow-by.

In the production process, the slab 5 is shaped after heating, after the shaping is accomplished, because the temperature reduction produces the shrinkage, the flange forging wraps on drift 8 easily, simultaneously because the upset extrusion, the flange forging can produce the bonding with lower mould 4, nevertheless the shrinkage can reduce the effect of bonding with lower mould 4, drift 8 power of unloading upwards promotes the restoration, compression spring begins the extension, under the effect of spring force, impel the flange forging to the direction motion of separating with lower mould 4, leave behind lower mould 4 blank holder 6 and push down the flange from drift 8, realize the separation of flange and mould.

A method for flange plate forging, impact extrusion and reverse upsetting composite forming comprises the following steps:

s1, forging: taking out the plate blank 5 and putting the plate blank into the counter bore 41, starting the hydraulic press, fixing the lower die holder 1, moving the punch 8 downwards to extrude the second compression spring 7, enabling the elastic force generated by the compression of the second compression spring 7 to act on the blank holder 6, forging and pressing the plate blank 5 by the blank holder 6 under the action of the elastic force of the spring until the blank holder 6 is contacted with the lower die 4, and clamping the plate blank 5 by the blank holder 6 and the lower die 4 together under the action of the elastic force of the spring;

s2, stretching and flanging: the punch 8 continues to move downwards, the punch 8 extrudes the material of the plate blank 5 to move towards the periphery through the guide hole, the guide hole is bent, stretched and thinned, the guide hole is gradually enlarged under the action of the punch 8, and the material around the guide hole overturns towards the hole wall of the inner hole of the lower die 4 along the outer ring of the punch 8;

s3, impact extrusion: when the thickness of the neck of the flange forging is smaller than that of the plate blank, after the plate blank 5 is contacted with the hole wall of the inner hole of the lower die 4, the punch 8 and the inner hole of the lower die 4 form a space smaller than the thickness of the plate blank 4, the plate blank 5 starts to become thin under the extrusion of the punch 8 along with the continuous downward movement of the punch 8, the redundant metal starts to flow downwards, and the neck of the flange becomes thin and long; when the thickness of the neck of the flange forging is larger than or equal to the thickness of the plate blank, the material of the plate blank 5 at the neck of the flange starts to be stretched and thinned under the extrusion of the punch 8;

s4, upsetting: the punch 8 continues to move downwards, the lower die 4 simultaneously moves downwards under the action of the punch 8, the backing ring 3 is enabled to extrude the first compression spring 2 to move downwards, the height of a closed cavity formed among the lower die base 1, the lower die 4, the blank holder 6 and the punch 8 is smaller and smaller, the blank 5 is in contact with the lower die base 1 after being flanged, the lower die base 1 reversely acts on a blank to realize reverse upsetting, the flanged rear end face is upset and leveled, meanwhile, redundant metal is extruded to the round corner of the upper end face until the closed cavity is filled, the die stops moving, and a flange forging piece with the size meeting the requirements is obtained. The reverse upsetting can be used for upsetting the neck of the flange, and the processing requirement that the thickness of the neck of the flange forging is larger than that of the plate blank can be met.

In the method for flange plate forging, impact extrusion and reverse upsetting composite forming, the pretreatment before the plate blank 5 is placed into the counter bore 41 in the step S1 comprises the following steps:

s11, blank making: selecting a plate with uniform thickness, cutting the plate according to the size requirement, processing a guide hole in the center of the blank after cutting, wherein the shape of the guide hole is circular or rectangular with a round angle corresponding to the shape of the inner hole of the flange, and obtaining a plate blank 5;

s12, heating: and then putting the plate blank 5 obtained in the step S1 into a heating furnace to be heated to 1150-1180 ℃.

The die and the method for flange plate forging, impact extrusion and reverse upsetting composite forming skillfully realize the movement in various opposite directions by means of the acting force and the reacting force brought by the compression and the recovery of the spring, realize various forming modes such as forging, stretching, flanging, impact extrusion, reverse upsetting and the like, ensure the integrity of a metal streamline, have higher mechanical property, only one power module is needed by stamping equipment, and the equipment requirement is reduced. The blank holder and the gasket are arranged, so that the mold opening cost is greatly reduced, the structure is compact, the practicability is high, and the maintenance and the replacement of the mold are convenient. The plate with the proper thickness is selected, the flange plate can be directly formed by forging and pressing according to different flange plate thicknesses, the flange neck can be directly formed by impact extrusion according to different flange neck thicknesses, machining allowance is reduced, and production cost is saved. When the punch is subjected to force unloading and reset, the flange and the die are automatically separated by means of the elastic force of the spring. The mold has wide applicability, and various flange plates, flange necks and flange inner hole shapes can be suitable.