CN116099924A - Hammer hot drawing forming die and forming method for thin-wall deep-cavity structural part - Google Patents

Hammer hot drawing forming die and forming method for thin-wall deep-cavity structural part Download PDF

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Publication number
CN116099924A
CN116099924A CN202211604442.8A CN202211604442A CN116099924A CN 116099924 A CN116099924 A CN 116099924A CN 202211604442 A CN202211604442 A CN 202211604442A CN 116099924 A CN116099924 A CN 116099924A
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China
Prior art keywords
ring
die
forming
plate
descending height
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Pending
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CN202211604442.8A
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Chinese (zh)
Inventor
于泓权
郑本强
李元
刘进涛
党赏
解洋
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Xian Aerospace Engine Co Ltd
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Xian Aerospace Engine Co Ltd
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Priority to CN202211604442.8A priority Critical patent/CN116099924A/en
Publication of CN116099924A publication Critical patent/CN116099924A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D22/00—Shaping without cutting, by stamping, spinning, or deep-drawing
    • B21D22/20—Deep-drawing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D37/00—Tools as parts of machines covered by this subclass
    • B21D37/10—Die sets; Pillar guides
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P40/00—Technologies relating to the processing of minerals
    • Y02P40/50—Glass production, e.g. reusing waste heat during processing or shaping
    • Y02P40/57—Improving the yield, e-g- reduction of reject rates

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Shaping Metal By Deep-Drawing, Or The Like (AREA)

Abstract

The invention discloses a hot drawing forming die and a forming method on a hammer of a thin-wall deep-cavity structural part, and aims to solve the problems that the thickness of the wall is reduced, the thickness of the wall is unevenly distributed and the like in the traditional plastic forming process of a plate cannot meet the subsequent processing requirement. The hammer upper hot drawing deep forming die for the thin-wall deep cavity structural part comprises an upper die, a lower die, an underpressing ring and a closing ring. When the raw material of the part is a titanium alloy plate with the thickness of 15mm-30mm, the part is formed by 3 times of fire, the heating temperature is 700-800 ℃, and the descending height of an upper die is 50-60mm when the fire is used. When the raw material of the part is a stainless steel plate with the thickness of 15mm-30mm, the part is formed by 3 times of fire, the heating temperature is 950-1050 ℃, and the descending height of an upper die is 50-60mm when the fire is used. As shown in FIG. 1, the thin-wall deep cavity structural part produced by the invention has uniform wall thickness distribution and high forming efficiency, and is suitable for mass production.

Description

Hammer hot drawing forming die and forming method for thin-wall deep-cavity structural part
Technical Field
The application relates to the technical field of rocket engines, in particular to a hammer hot drawing forming die and a forming method for a thin-wall deep-cavity structural part.
Background
The thin-wall deep-cavity structural part is used as a key part in a liquid rocket engine storage tank, and has extremely high requirements on the overall performance and the size of the part. The rebound and local thinning of the thin-wall deep cavity structural part formed by adopting the traditional press cold drawing process are serious, the wall thickness of the formed part is unevenly distributed, the cold drawing process requires a plurality of transition forming dies, the cost is high, the processing period is long, and the production progress and delivery requirements of the part are seriously affected.
Disclosure of Invention
The invention provides a hot drawing forming die and a forming method on a hammer of a thin-wall deep-cavity structural part, which are used for solving the problems of rebound, serious local thinning, uneven wall thickness distribution and the like in the cold drawing forming process of the thin-wall deep-cavity structural part by adopting a traditional press.
In a first aspect, a hot drawing forming die on a hammer of a thin-wall deep cavity structural part is provided, the hot drawing forming die comprises an upper die and a lower die, an annular containing cavity is arranged at the periphery of an opening of a forming deep cavity of the lower die, the die further comprises a closing ring, the closing ring is arranged in the annular containing cavity, and an inner surface of the closing ring is matched with an outer surface of the upper die;
in the mold forming process, the deep cavity part of the plate material penetrates through the closing ring through the upper mold to extend into the deep cavity, and is in deep drawing forming with the lower mold, and the part of the plate material located at the periphery of the deep cavity is clamped between the closing ring and the lower mold.
The closing ring is used for reducing the size of a round angle at the opening of the part. The closing ring 2 can also have a positioning function. In the forming process of the part, the upper die moves downwards, the gap between the upper die and the closing ring is smaller and smaller, and the positioning accuracy is improved. In addition, the temperature of the upper die can be gradually increased and heated to expand due to temperature conduction in the part forming process, and the upper die and the closing ring are in danger of clamping. By adopting the inclined plane matching, the problem that the upper die is clamped with the closing ring can be conveniently solved.
With reference to the first aspect, in certain implementations of the first aspect, the collar protrudes from an opening of the annular cavity.
With reference to the first aspect, in certain implementation manners of the first aspect, a height of the closing ring protruding out of the annular cavity is 30-40 mm.
With reference to the first aspect, in certain implementation manners of the first aspect, a side of the collar facing the upper die is provided with an inclined step, and the inclined step is used for inserting a pry bar.
Because precooling contracts in the part forming process, an upper die can be held frequently, so that the part cannot be taken out of the die, and when the inclined step on the upper end face of the closing-in ring is used for holding the die between the part and the die, a crow bar can be inserted, and the die is removed.
With reference to the first aspect, in certain implementations of the first aspect, the collar meets at least one of:
the reserved gap between the outer contour of the closing ring and the inner molded surface of the lower die is 6-8mm;
the reserved gap between the inner surface of the closing ring and the outer contour of the upper die is 2-3mm.
With reference to the first aspect, in certain implementation manners of the first aspect, the mold further includes an undervoltage ring, the undervoltage ring surrounds the periphery of the plate material and is located in the annular cavity, the undervoltage ring is used for being matched with the periphery of the plate material, and in the mold forming process, the undervoltage ring is clamped between the lower mold and the closing ring.
The underpressing ring has 2 functions: firstly, the positioning function is that the inner diameter of the underpressing ring is slightly larger than the outer diameter of the plate, and the underpressing ring can be used for positioning the position of the plate before forming, so that the problem of dislocation of the plate is avoided. Secondly, limiting, because the free forging hammer is adopted in part forming, the stroke of the hammer head cannot be accurately controlled. In the forming process, after the lower end face of the closing ring is contacted with the underpressing ring, the upper die can not move downwards any more, and the problem of flash thinning of the formed part can be avoided.
With reference to the first aspect, in certain implementations of the first aspect, the under-voltage ring satisfies at least one of:
the reserved gap between the outer contour of the underpressing ring and the inner molded surface of the lower mold is 2-3mm;
the reserved gap between the inner surface of the underpressing ring and the outer contour of the upper die is 2-3mm;
the thickness of the underpressed ring is the same as that of the plate material.
In a second aspect, there is provided a method of hot drawing on hammer forming a thin wall deep cavity structural part, the method employing a die as described in the last two implementations of the first aspect, the method comprising:
heating the plate material to a hot drawing forming temperature by a first fire, preserving heat, taking out the plate material, placing the plate material in a lower die, performing downward pressing forming by using an upper die, controlling the descending height of the upper die to be the first descending height, and returning to a furnace for heating after forming;
heating the plate material to a hot drawing forming temperature by a second fire, preserving heat, taking out the plate material, placing the plate material in a lower die, using an upper die to perform downward pressing forming, controlling the descending height of the upper die to be a second descending height, and returning to a furnace for heating after forming, wherein the second descending height is larger than the first descending height;
and heating the plate to a hot drawing forming temperature by third fire, preserving heat, taking out the plate, placing the plate in a lower die, placing an under-pressure ring in the center of the upper end face of the lower die, placing a closing ring in the center of the upper end face of the under-pressure ring, performing downward pressing forming by using the upper die, controlling the descending height of the upper die to be higher than the second descending height, and enabling the third descending height to meet the contact of the closing ring and the under-pressure ring.
With reference to the second aspect, in certain implementations of the second aspect, the sheet is a 15mm-30mm stainless steel sheet, and the method satisfies at least one of the following:
the hot drawing forming temperature is 700-800 ℃;
the heat preservation time is 20-40min;
the first descending height is 50-60mm;
the second descending height is 60-90mm;
the third descending height is 180-190mm.
With reference to the second aspect, in certain implementations of the second aspect, the sheet is a 15mm-30mm stainless steel sheet, and the method satisfies at least one of the following:
the hot drawing forming temperature is 950-1050 ℃;
the heat preservation time is 30-50min;
the first descending height is 50-60mm;
the second descending height is 60-90mm;
the third descending height is 180-190mm.
Compared with the prior art, the scheme provided by the application at least comprises the following beneficial technical effects:
1. the thin-wall deep cavity structural part formed by adopting the hot drawing forming die on the hammer and the forming method has small rebound quantity and uniform wall thickness distribution.
2. The die has reasonable structure and strong universality, and is suitable for forming titanium alloy and stainless steel parts.
3. The hot drawing and deep forming method of the thin-wall deep-cavity structural part is reasonable, the forming fire is less, the production efficiency can be greatly improved, and the die cost is reduced.
Drawings
FIG. 1 is a drawing of a thin-wall deep cavity structural part forming die;
FIG. 2 is a top view of the cinch ring;
FIG. 3 is a schematic diagram of a thin-wall deep cavity structural part raw material sheet.
Detailed Description
The present application is described in further detail below with reference to the drawings and specific examples.
Fig. 1 is a schematic diagram of a hot drawing forming die on a hammer for a thin-wall deep-cavity structural part according to an embodiment of the present application. Fig. 3 is a schematic diagram of a thin-wall deep-cavity structural part raw material plate.
The hot drawing forming die on the hammer of the thin-wall deep-cavity structural part can comprise an upper die 1, a closing-in ring 2, an undervoltage ring 3 and a lower die 4. The lower die 4 can form a deep cavity for forming the raw material sheet. The lower die 4 is also provided with an annular containing cavity at the periphery of the deep cavity opening, and the annular containing cavity is used for containing the closing-in ring 2 and the under-pressure ring 3. The underpressing ring 3 is placed in the annular containing cavity and is arranged in the center of the upper end face of the lower die 4. The choke coil 2 is arranged in the center of the upper end face of the under-voltage ring 3. The outer diameter sizes of the choke ring 2 and the under-pressure ring 3 are phi 580-phi 600mm multiplied by 90mm and phi 580-phi 600mm multiplied by 15mm respectively.
The choke ring 2 is used for reducing the round angle size of the part opening. When the closing ring 2 is put into the lower die 4, the closing ring 2 can exceed the opening of the lower die 4 by 30-40 mm. The outer contour of the closing ring 2 is designed according to the size of the molded surface of the lower die 4, and a reserved gap is 6-8mm. The inner profile size is designed according to the profile size of the upper die 1, and the reserved gap is 2-3mm. Fig. 2 shows a top view of the closing ring 2. Because precooling contracts in the part forming process, an upper die can be held frequently, so that the part cannot be taken out of the die, and when the inclined step on the upper end face of the closing ring 2 is used for holding the die between the part and the die, a crow bar can be inserted, and the die is removed.
The closing ring 2 can also have a positioning function. In the forming process of the part, the upper die 1 moves downwards, the gap between the upper die and the closing ring 2 is smaller and smaller, and the positioning accuracy is improved. In addition, the temperature of the upper die 1 can be gradually increased and heated to expand due to temperature conduction in the part forming process, so that the upper die 1 and the closing ring 2 are in danger of being clamped. By adopting the inclined plane matching, the clamping problem of the upper die 1 and the closing ring 2 can be conveniently solved.
The inner diameter of the underpressing ring 3 is designed according to the outer diameter of the formed plate, the reserved gap is 2-3mm, the outer diameter is designed according to the inner diameter of the platform of the lower die 4, the reserved gap is 2-3mm, and the height is designed according to the flash size of the part.
The underpressed ring 3 has 2 functions: firstly, the positioning function is that the inner diameter of the underpressing ring is slightly larger than the outer diameter of the plate, and the underpressing ring can be used for positioning the position of the plate before forming, so that the problem of dislocation of the plate is avoided. Secondly, limiting, because the free forging hammer is adopted in part forming, the stroke of the hammer head cannot be accurately controlled. In the forming process, after the lower end face of the closing ring 2 is contacted with the underpressing ring 3, the upper die 1 can not move downwards any more, and the problem of flash thinning of the formed part can be avoided.
The embodiment of the application also provides a hot drawing and forming method on the hammer of the thin-wall deep-cavity structural part.
In some embodiments, when the thin-wall deep cavity structural part raw material is a 15mm-30mm (e.g., 25 mm) titanium alloy sheet, this is accomplished as follows.
Heating the plate 5 to 700-800 ℃ (e.g. 780 ℃) by first fire, keeping the temperature for 20-40min (e.g. 30 min), taking out the plate 5, placing the plate into the lower die 4, using the upper die 1 to perform pressing forming, controlling the descending height of the upper die 1 to be 50-60mm (e.g. 60 mm), and returning to the furnace for heating after forming.
And heating the plate material to 700-800 ℃ (e.g. 780 ℃) by a second fire, keeping the temperature for 20-40min (e.g. 30 min), taking out the plate material 5, placing the plate material into the lower die 4, using the upper die 1 to perform pressing forming, controlling the descending height of the upper die 1 to be 80-90mm (e.g. 90 mm), and returning to the furnace for heating after forming.
And heating the plate 5 to 700-800 ℃ (e.g. 780 ℃) by third fire, keeping the temperature for 20-40min (e.g. 30 min), taking out the plate 5, placing the plate 5 in the lower die 4, placing the under-pressure ring 3 in the center of the upper end face of the lower die 4, placing the mouth-closing ring 2 in the center of the upper end face of the under-pressure ring 3, performing pressing forming by using the upper die 1, controlling the descending height of the upper die 1 to be 180-190mm (e.g. 190 mm), and completing forming after the mouth-closing ring 2 contacts with the under-pressure ring 3.
In other embodiments, when the thin-wall deep cavity structural part stock is 15mm-30mm (e.g., 25 mm) stainless steel plate, this is accomplished as follows.
Heating the plate 5 to 950-1050 ℃ (for example, 1000 ℃), keeping the temperature for 30-50min (for example, 40 min) by a first fire, taking out the plate 5, placing the plate into a lower die 4, performing pressing forming by using an upper die 1, controlling the descending height of the upper die 1 to be 50-60mm (for example, 60 mm), and returning to the furnace for heating after forming.
And heating the plate 5 to 950-1050 ℃ (for example, 1000 ℃), keeping the temperature for 30-50min (for example, 40 min), taking out the plate 5, placing the plate into the lower die 4, performing pressing forming by using the upper die 1, controlling the descending height of the upper die 1 to be 80-90mm (for example, 90 mm), and returning to the furnace for heating after forming.
And heating the plate 5 to 950-1050 ℃ (for example, 1000 ℃), keeping the temperature for 30-50min (for example, 40 min), taking out the plate 5, placing the plate 5 in the lower die 4, placing the under-pressure ring 3 in the center of the upper end face of the lower die 4, placing the mouth-closing ring 2 in the center of the upper end face of the under-pressure ring 3, performing pressing forming by using the upper die 1, controlling the upper die 1 to descend by 180-190mm (for example, 190 mm), and completing forming after the mouth-closing ring 2 contacts with the under-pressure ring 3.
The thin-wall deep cavity structural part produced by the forming die and the forming process has small rebound and uniform wall thickness distribution.
While the invention has been described in terms of the preferred embodiment, it is not intended to limit the invention, but it will be apparent to those skilled in the art that variations and modifications can be made without departing from the spirit and scope of the invention, and therefore the scope of the invention is defined in the appended claims.

Claims (10)

1. The hot drawing deep forming die comprises an upper die (1) and a lower die (4), and is characterized in that an annular containing cavity is arranged at the periphery of a forming deep cavity opening of the lower die (4), the die further comprises a closing-in ring (2), the closing-in ring (2) is arranged in the annular containing cavity, and an inner surface of the closing-in ring (2) is matched with an outer surface of the upper die (1);
in the mold forming process, a deep cavity part of a plate material (5) penetrates through the closing ring (2) through the upper mold (1) to stretch into the deep forming cavity and is in deep drawing forming with the lower mold (4), and the part of the plate material (5) located at the periphery of the deep cavity is clamped between the closing ring (2) and the lower mold (4).
2. A mould according to claim 1, characterized in that the collar (2) protrudes out of the opening of the annular cavity.
3. A mould according to claim 2, characterized in that the height of the collar (2) protruding from the annular cavity is 30-40 mm.
4. Mould according to claim 1, characterized in that the side of the closing ring (2) facing the upper mould (1) is provided with an inclined step for inserting a crow bar.
5. The mould according to any one of claims 1, characterized in that said collar (2) satisfies at least one of the following:
the reserved gap between the outer contour of the closing ring (2) and the inner molded surface of the lower mold (4) is 6-8mm;
the reserved gap between the inner surface of the closing ring (2) and the outer contour of the upper die (1) is 2-3mm.
6. The die according to any one of claims 1 to 5, further comprising an underpressure ring (3), wherein the underpressure ring (3) surrounds the periphery of the plate (5) and is located in the annular cavity, the underpressure ring (3) is used for being matched with the periphery of the plate (5), and the underpressure ring (3) is clamped between the lower die (4) and the closing-in ring (2) in the die forming process.
7. The mould according to claim 6, characterized in that said under-pressure ring (3) satisfies at least one of the following:
the reserved gap between the outer contour of the under-pressure ring (3) and the inner molded surface of the lower mold (4) is 2-3mm;
the reserved gap between the inner profile of the under-pressure ring (3) and the outer profile of the upper die (1) is 2-3mm;
the thickness of the undervoltage ring (3) is the same as that of the plate material (5).
8. A method of hot drawing on hammer deep forming thin wall deep cavity structural parts, characterized in that the method employs a die as defined in claim 6 or 7, the method comprising:
heating the plate (5) to a hot drawing forming temperature by a first fire, preserving heat, taking out the plate (5), placing the plate into a lower die (4), performing downward pressing forming by using an upper die (1), controlling the descending height of the upper die (1) to be the first descending height, and returning to a furnace for heating after forming;
heating the plate (5) to a hot drawing forming temperature by a second fire, preserving heat, taking out the plate (5), placing the plate into a lower die (4), performing downward pressing forming by using an upper die (1), controlling the descending height of the upper die (1) to be a second descending height, and returning to a furnace for heating after forming, wherein the second descending height is larger than the first descending height;
and heating the plate (5) to a hot drawing forming temperature by third fire, preserving heat, taking out the plate (5), placing the plate (5) in a lower die (4), placing the underpressure ring (3) in the center of the upper end face of the lower die (4), placing the closing ring (2) in the center of the upper end face of the underpressure ring (3), using the upper die (1) to perform downward pressing forming, controlling the upper die (1) to descend to a third descending height, wherein the third descending height is larger than the second descending height, and the third descending height meets the contact of the closing ring (2) and the underpressure ring (3).
9. The method according to claim 8, characterized in that the sheet (5) is a 15-30 mm stainless steel sheet, the method satisfying at least one of the following:
the hot drawing forming temperature is 700-800 ℃;
the heat preservation time is 20-40min;
the first descending height is 50-60mm;
the second descending height is 60-90mm;
the third descending height is 180-190mm.
10. The method according to claim 8, characterized in that the sheet (5) is a 15-30 mm stainless steel sheet, the method satisfying at least one of the following:
the hot drawing forming temperature is 950-1050 ℃;
the heat preservation time is 30-50min;
the first descending height is 50-60mm;
the second descending height is 60-90mm;
the third descending height is 180-190mm.
CN202211604442.8A 2022-12-13 2022-12-13 Hammer hot drawing forming die and forming method for thin-wall deep-cavity structural part Pending CN116099924A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202211604442.8A CN116099924A (en) 2022-12-13 2022-12-13 Hammer hot drawing forming die and forming method for thin-wall deep-cavity structural part

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202211604442.8A CN116099924A (en) 2022-12-13 2022-12-13 Hammer hot drawing forming die and forming method for thin-wall deep-cavity structural part

Publications (1)

Publication Number Publication Date
CN116099924A true CN116099924A (en) 2023-05-12

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Country Status (1)

Country Link
CN (1) CN116099924A (en)

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