CN112719085B - A forming die for preventing stainless steel pipe from cracking and wrinkling - Google Patents

Abstract

The invention discloses a forming die for preventing stainless steel pipes from cracking and wrinkling, which comprises a supporting table, a fixed die fixing plate and a movable die top plate, wherein the fixed die fixing plate is arranged on the supporting table, the movable die top plate is arranged above the fixed die fixing plate, a stamping forming structure is arranged between the fixed die fixing plate and the movable die top plate, a stretching and anti-deforming member is arranged in a pre-press bending die, so that in the pre-press bending operation process, the pipe fitting is subjected to reverse stretching deformation at the position to be subjected to pressurizing deformation, so that the wall thickness and the stress state of the pipe fitting at the bending position are improved in a stretching reverse deformation mode, the situation that the pipe fitting is locally cracked in the subsequent pressurizing forming process is avoided, meanwhile, the pressurizing forming assembly cooperates with the hydraulic pressurizing forming component to perform integrated operation, the pipe fitting after the pre-pressurizing bending forming is placed into the pressurizing forming assembly, and the hydraulic pressurizing forming component is controlled to perform internal high-pressure forming on the pipe fitting.

Description

A forming die for preventing stainless steel pipe from cracking and wrinkling

Technical Field

The invention relates to the technical field of stainless steel pipe processing, in particular to a forming die for preventing a stainless steel pipe from cracking and wrinkling.

Background Art

For products with high requirements for pipe surface contour, the current mature technology is generally manufactured using the internal high pressure process. Internal high pressure forming is also called hydraulic forming or hydraulic forming. It is a material forming process that uses liquid as a forming medium and controls the internal pressure and material flow to achieve the purpose of forming hollow parts. The principle of internal high pressure forming is to press the tube blank into the mold cavity through internal pressurization and axial force feeding to form it into the required workpiece. For parts with curved axes, the tube blank needs to be pre-bent into a shape close to the part, and then pressurized to form. The components formed by internal high pressure forming are light in weight, good in product quality, flexible in product design, simple in process, and have the characteristics of near-net forming and green manufacturing. Therefore, they are widely used in the field of lightweight automobiles. Axially bent special-shaped pipe fittings are widely used in the fields of automobiles, aviation, aerospace, etc., and are often used in automobile air intake parts, body structures, and aerospace system pipelines. The liquid filling forming process is the main method for forming such tubular parts. The prior art requires two sets of internal high pressure forming molds, namely one set of liquid filling liquid bending preforming molds and one set of internal high pressure forming molds. Otherwise, the risk of cracking of the pipe fittings is very high, which can hardly meet the production needs. The mold cost is high, and the cost of manual operation is required later. In view of this, in-depth research was conducted on the above-mentioned problems, and this case was thus created.

Summary of the invention

The purpose of the present invention is to solve the above problems, and a forming die is designed to prevent the stainless steel pipe from cracking and wrinkling, thereby solving the problems raised in the background technology.

The technical solution of the present invention to achieve the above-mentioned purpose is: a forming mold for preventing cracking and wrinkling of a stainless steel pipe, comprising a support platform, a fixed mold fixing plate and a movable mold top plate, wherein the fixed mold fixing plate is arranged on the support platform, the movable mold top plate is arranged above the fixed mold fixing plate, and a pressure forming structure is arranged between the fixed mold fixing plate and the movable mold top plate;

The pressurizing and forming structure comprises: a pre-bending die assembly and a filling and forming assembly, wherein the lower portion of the pre-bending die assembly is arranged on a fixed die plate, and the upper portion of the pre-bending die assembly is arranged on a lower end surface of a movable die top plate, and a tensile anti-deformation component is arranged in the pre-bending die assembly, and the filling and forming assembly is arranged on one side of the pre-bending die assembly, and the upper and lower portions are respectively connected to the fixed die plate and the movable die top plate, and hydraulic filling and forming components are arranged on both sides of the filling and forming assembly.

The pre-bending die assembly comprises: a pre-bending lower die and a pre-bending upper die, wherein the pre-bending lower die is arranged on a fixed die plate, and the pre-bending upper die is arranged on a movable die top plate and is symmetrically arranged with the pre-bending lower die.

The contact surfaces of the pre-pressing bending lower die and the pre-pressing bending upper die are S-shaped curved surfaces that match each other.

Pre-pressing forming grooves are respectively provided on the inner sides of the contact surfaces of the pre-pressing bending lower die and the pre-pressing bending upper die.

The stretching anti-deformation component is arranged in the pre-pressing forming groove along a certain interval, and the stretching anti-deformation component is a block-shaped protrusion made of hard metal material.

The filling and forming assembly comprises: a filling lower mold and a filling upper mold, wherein the filling lower mold is arranged on the fixed mold fixing plate, and the filling upper mold is arranged on the lower end surface of the movable mold top plate and is symmetrically arranged with the filling lower mold.

The lower filling die and the upper filling die are respectively and symmetrically provided with forming and shaping grooves, and the shapes of the forming and shaping grooves are consistent with the external shape of the pipe to be processed.

A plurality of ejector pins are arranged in the lower filling die.

The upper end surface of the filling lower die is provided with a plurality of arc-shaped matching grooves, and the lower end surface of the filling upper die is provided with a plurality of arc-shaped convex blocks, and the arc-shaped convex blocks match the arc-shaped matching grooves.

The filling pressure of the hydraulic filling component is 0-30MPa.

The forming die for preventing cracking and wrinkling of stainless steel pipes made by the technical solution of the present invention is provided with a stretching anti-deformation component in the pre-bending die, so that in the pre-bending process, the position of the pipe to be pressurized and deformed is reversely stretched and deformed, thereby increasing the wall thickness and stress state of the pipe at the bending position by stretching and anti-deformation, thereby avoiding local cracking of the pipe during the subsequent pressurization and forming process. At the same time, the filling and forming component cooperates with the hydraulic filling and forming component to perform integrated operation, and the pipe after pre-bending is placed in the filling and forming component, and the hydraulic filling and forming component is controlled to perform internal high-pressure pre-forming on the pipe. The hydraulic pressure is 10-15MPa, so that the pipe is initially formed. After the initial forming, the filling and forming component is controlled to close the mold, and the hydraulic pressure is increased to 25MPa, so that the axially bent special-shaped pipe is formed and shaped under the cooperation of the filling and forming component, and the forming quality is ensured, while effectively avoiding the cracking and wrinkling of the pipe, and the pipe scratches or dead wrinkles caused by direct closing of the mold are solved by only one set of internal high-pressure forming molds, thereby reducing the processing cost of producing such products.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an axonometric view of a molding die for preventing cracking and wrinkling of a stainless steel tube according to the present invention in a mold-closing state.

FIG. 2 is an axonometric view of a forming mold for preventing cracking and wrinkling of a stainless steel tube according to the present invention in an open mold state.

FIG. 3 is a schematic diagram of the top view of the structure of FIG. 2 of a forming mold for preventing a stainless steel tube from cracking and wrinkling according to the present invention.

FIG. 4 is a bottom view structural schematic diagram of FIG. 2 of a forming mold for preventing cracking and wrinkling of a stainless steel tube according to the present invention.

5 is a schematic diagram of the main cross-sectional structure of a pre-bending die assembly of a forming die for preventing cracking and wrinkling of a stainless steel tube according to the present invention in a mold-closing state.

FIG6 is a schematic structural diagram of a finished product processed by a forming die for preventing cracking and wrinkling of a stainless steel tube according to the present invention.

In the figure: 1-support platform; 2-fixed die fixing plate; 3-movable die top plate; 4-stretching anti-deformation component; 5-pre-bending lower die; 6-pre-bending upper die; 7-pre-bending forming groove; 8-filling lower die; 9-filling upper die; 10-forming shaping groove; 11-ejection pin; 12-hydraulic filling component.

DETAILED DESCRIPTION

The present invention is described in detail below in conjunction with the accompanying drawings. As shown in FIGS. 1-6, a forming mold for preventing cracking and wrinkling of a stainless steel pipe comprises a support platform 1, a fixed mold fixing plate 2 and a movable mold top plate 3, wherein the fixed mold fixing plate 2 is arranged on the support platform 1, and the movable mold top plate 3 is arranged above the fixed mold fixing plate 2, and a pressure forming structure is arranged between the fixed mold fixing plate 2 and the movable mold top plate 3; the pressure forming structure comprises: a pre-bending mold assembly and a filling forming assembly, the lower part of the pre-bending mold assembly is arranged on the fixed mold fixing plate 2, and the pre-bending mold assembly is provided with a pre-bending mold assembly. The upper part of the bending die assembly is arranged on the lower end surface of the movable die top plate 3, and a tensile anti-deformation component 4 is arranged in the pre-bending die assembly. The filling and forming component is arranged on one side of the pre-bending die assembly, and the upper and lower parts are respectively connected to the fixed die fixed plate 2 and the movable die top plate 3, and hydraulic filling components 12 are arranged on both sides of the filling and forming component; the pre-bending die assembly includes: a pre-bending lower die 5 and a pre-bending upper die 6, the pre-bending lower die 5 is arranged on the fixed die fixed plate 2, the pre-bending upper die 6 is arranged on the movable die top plate 3, and The pre-pressing bending lower die 5 is arranged symmetrically; the contact surfaces of the pre-pressing bending lower die 5 and the pre-pressing bending upper die 6 are S-shaped curved surfaces that match each other; the inner sides of the contact surfaces of the pre-pressing bending lower die 5 and the pre-pressing bending upper die 6 are respectively provided with pre-pressing forming grooves 7; the stretching anti-deformation member 4 is arranged in the pre-pressing forming groove 7 along a certain interval, and the stretching anti-deformation member 4 is a block-shaped protrusion made of hard metal; the filling forming component includes: a filling lower die 8 and a filling upper die 9, the filling lower die 8 is arranged on the fixed die fixed plate 2, and the filling upper die 9 is arranged on the movable die The mold top plate 3 is arranged on the lower end surface and symmetrically with the filling lower mold 8; the filling lower mold 8 and the filling upper mold 9 are respectively symmetrically provided with forming and shaping grooves 10, and the shape of the forming and shaping grooves 10 is consistent with the external shape of the pipe to be processed; a plurality of ejector pins 11 are arranged in the filling lower mold 8; a plurality of arc-shaped matching grooves are arranged on the upper end surface of the filling lower mold 8, and a plurality of arc-shaped protrusions are arranged on the lower end surface of the filling upper mold 9, and the arc-shaped protrusions match the arc-shaped matching grooves; the filling pressure of the hydraulic filling component 12 is 0-30MPa.

The characteristics of this embodiment are as follows: it includes a support platform 1, a fixed mold fixing plate 2 and a movable mold top plate 3, the fixed mold fixing plate 2 is arranged on the support platform 1, the movable mold top plate 3 is arranged above the fixed mold fixing plate 2, and a pressure forming structure is arranged between the fixed mold fixing plate 2 and the movable mold top plate 3; the pressure forming structure includes: a pre-bending mold assembly and a filling forming assembly, the lower part of the pre-bending mold assembly is arranged on the fixed mold fixing plate 2, the upper part of the pre-bending mold assembly is arranged on the lower end surface of the movable mold top plate 3, a tensile anti-deformation component 4 is arranged in the pre-bending mold assembly, the filling forming assembly is arranged on one side of the pre-bending mold assembly, and the upper and lower parts are respectively connected to the fixed mold fixing plate 2 and the movable mold top plate 3, and hydraulic filling forming components 12 are arranged on both sides of the filling forming assembly; the forming mold for preventing the stainless steel pipe from cracking and wrinkling is provided with a tensile anti-deformation component 4 in the pre-bending mold, so that during the pre-bending operation, the pipe to be pressurized is deformed The forming position is stretched and deformed in the reverse direction, thereby increasing the wall thickness and stress state of the pipe at the bending position by stretching and reverse deformation, thereby avoiding local cracking of the pipe during the subsequent filling and pressing forming process. At the same time, the filling and forming component cooperates with the hydraulic filling and forming component 12 to perform integrated operation, and the pipe after pre-bending is placed in the filling and forming component, and the hydraulic filling and forming component 12 is controlled to perform internal high-pressure pre-forming on the pipe. The hydraulic pressure is 10-15MPa, so that the pipe is initially formed. After the initial forming, the filling and forming component is controlled to close the mold, and the hydraulic pressure is increased to 25MPa. Therefore, under the cooperation of the filling and forming component, the forming and shaping of the axially bent special-shaped pipe is realized, while ensuring the forming quality, the cracking and wrinkling of the pipe are effectively avoided, and the scratches or dead wrinkles of the pipe caused by direct mold closing are solved. Only one set of internal high-pressure forming molds is used to reduce the processing cost of producing such products.

By those skilled in the art, the components in this case are connected in sequence. The specific connection and operation sequence should refer to the following working principle. The detailed connection means are well-known technologies in the art. The following mainly introduces the working principle and process.

Embodiment: As can be seen from the attached drawings 1-6 of the specification, this scheme includes a support platform 1, a fixed mold fixing plate 2 and a movable mold top plate 3, and their positional relationship and connection relationship are as follows: the fixed mold fixing plate 2 is arranged on the support platform 1, and the movable mold top plate 3 is arranged above the fixed mold fixing plate 2, and a pressure forming structure is arranged between the fixed mold fixing plate 2 and the movable mold top plate 3; the above-mentioned pressure forming structure includes: a pre-bending mold assembly and a filling forming assembly, the lower part of the pre-bending mold assembly is arranged on the fixed mold fixing plate 2, the upper part of the pre-bending mold assembly is arranged on the lower end surface of the movable mold top plate 3, a tensile anti-deformation component 4 is arranged in the pre-bending mold assembly, the filling forming assembly is arranged on one side of the pre-bending mold assembly, and the upper and lower parts are respectively connected to the fixed mold fixing plate 2 and the movable mold top plate 3, hydraulic filling components 12 are arranged on both sides of the filling forming assembly, and a tensile anti-deformation component 4 is arranged in the pre-bending mold, so that during the pre-bending operation, the pipe fitting The position to be pressurized and deformed is subjected to reverse stretching deformation, thereby increasing the wall thickness and stress state of the pipe at the bending position by stretching and reverse deformation, thereby avoiding local cracking of the pipe during the subsequent pressurizing and forming process. At the same time, the pressurizing and forming component cooperates with the hydraulic filling and forming component 12 for integrated operation, and the pre-pressed and bent pipe is placed in the pressurizing and forming component, and the hydraulic filling and forming component 12 is controlled to perform internal high-pressure preforming on the pipe. The hydraulic pressure is 10-15MPa, so that the pipe is initially formed. After the initial forming, the pressurizing and forming component is controlled to close the mold, and the hydraulic pressure is increased to 25MPa. Therefore, under the cooperation of the pressurizing and forming component, the forming and shaping of the axially bent special-shaped pipe is realized, which ensures the forming quality while effectively avoiding cracking and wrinkling of the pipe. To solve the problem of pipe scratches or dead wrinkles caused by direct closing of the mold, only one set of internal high-pressure forming mold is used, thereby reducing the processing cost of producing such products.

In the specific implementation process, the above-mentioned pre-stressing and bending mold assembly includes: a pre-stressing and bending lower mold 5 and a pre-stressing and bending upper mold 6, the pre-stressing and bending lower mold 5 is arranged on the fixed mold fixed plate 2, and the pre-stressing and bending upper mold 6 is arranged on the movable mold top plate 3, and is symmetrically arranged with the pre-stressing and bending lower mold 5, wherein the contact surfaces of the pre-stressing and bending lower mold 5 and the pre-stressing and bending upper mold 6 are S-shaped curved surfaces that match each other, and the inner sides of the contact surfaces of the above-mentioned pre-stressing and bending lower mold 5 and the pre-stressing and bending upper mold 6 are respectively provided with pre-stressing forming grooves 7. When in use, the raw material pipe fitting is placed in the pre-stressing and bending groove 7 of the pre-stressing and bending lower mold 5, and the movable mold top plate 3 is controlled to be pressed downward, so that the pre-stressing and bending upper mold 6 moves downward, and the pre-stressing and bending lower mold 5 and the pre-stressing and bending upper mold 6 are closed. Under the action of external force, the pipe fitting is pre-stressed and bent, and at the same time, the tensile anti-deformation component 4 in the pre-stressing and bending groove 7 reversely stretches and deforms the corresponding position of the pipe wall, thereby causing deformation at a specific position on the pipe wall.

In the specific implementation process, the above-mentioned tensile anti-deformation component 4 is arranged in the pre-pressing forming groove 7 along a certain interval. The tensile anti-deformation component 4 is a block-shaped protrusion made of hard metal material. The size of the block-shaped protrusion can be adjusted according to the size of the pipe and the thickness of the pipe wall.

In the specific implementation process, the above-mentioned filling and forming components include: a filling lower mold 8 and a filling upper mold 9. The filling lower mold 8 is arranged on the fixed mold fixed plate 2, and the filling upper mold 9 is arranged on the lower end surface of the movable mold top plate 3, and is symmetrically arranged with the filling lower mold 8, wherein the filling lower mold 8 and the filling upper mold 9 are respectively symmetrically provided with forming and shaping grooves 10, and the shape of the forming and shaping grooves 10 is consistent with the external shape of the pipe to be processed. When in use, the pre-bent pipe is placed in the forming and shaping groove 10, and the two ends of the hydraulic filling component 12 are respectively connected to the two ends of the pipe for pressurization. The filling pressure is 10-15MPa, so that the pipe is pre-formed. After pre-forming, the filling upper mold 9 is controlled to close the filling lower mold 8, and the filling pressure is further increased to 25MPa, so that the pipe completes the forming and shaping operation in the mold.

In the specific implementation process, a plurality of ejector pins 11 are arranged in the above-mentioned filling lower mold 8. After the forming and shaping operation is completed, the filling upper mold 9 is controlled to separate from the filling lower mold 8, and the ejector pins 11 are controlled to move upward to eject the finished pipe fittings from the filling lower mold 8 for easy material removal.

In the specific implementation process, the upper end face of the above-mentioned filling lower mold 8 is provided with a plurality of arc-shaped matching grooves, and the lower end face of the filling upper mold 9 is provided with a plurality of arc-shaped protrusions, and the arc-shaped protrusions match the arc-shaped matching grooves. Through the cooperation of the arc-shaped protrusions and the arc-shaped matching grooves, the connection effect of the mold can be effectively improved, the matching degree between the filling lower mold 8 and the filling upper mold 9 is ensured, and the molding quality of the pipe fittings is improved.

In the specific implementation process, the filling pressure of the hydraulic filling component 12 is 0-30MPa, and the main mold is matched to perform segmented filling operation.

To sum up, the forming mold for preventing the cracking and wrinkling of the stainless steel pipe is provided with a stretching anti-deformation component 4 in the pre-bending mold, so that during the pre-bending operation, the position of the pipe to be pressurized and deformed is reversely stretched and deformed, thereby increasing the wall thickness and stress state of the pipe at the bending position by stretching and reverse deformation, thereby avoiding local cracking of the pipe during the subsequent pressurizing and forming process. At the same time, the filling and forming component cooperates with the hydraulic filling and forming component 12 to perform integrated operation, and the pipe after pre-bending is placed in the filling and forming component, and the hydraulic filling and forming component 12 is controlled to perform internal high-pressure pre-forming on the pipe. The hydraulic pressure is 10-15MPa, so that the pipe is initially formed. After the initial forming, the filling and forming component is controlled to close the mold and increase the hydraulic pressure to 25MPa. Therefore, under the cooperation of the filling and forming component, the forming and shaping of the axially bent special-shaped pipe is realized, while ensuring the forming quality, the cracking and wrinkling of the pipe is effectively avoided, and the scratches or dead wrinkles of the pipe caused by direct closing of the mold are solved. Only one set of internal high-pressure forming molds is used to reduce the processing cost of producing such products.

The above technical solutions only reflect the preferred technical solutions of the technical solutions of the present invention. Some changes that may be made to certain parts thereof by technicians in this technical field all reflect the principles of the present invention and fall within the protection scope of the present invention.

Claims (5)

1. The forming die for preventing cracking and wrinkling of the stainless steel pipe comprises a supporting table (1), a fixed die fixing plate (2) and a movable die top plate (3), and is characterized in that the fixed die fixing plate (2) is arranged on the supporting table (1), the movable die top plate (3) is arranged above the fixed die fixing plate (2), and a pressurizing forming structure is arranged between the fixed die fixing plate (2) and the movable die top plate (3);

The pressurizing forming structure comprises: the pre-bending die assembly and the filling forming assembly are arranged on the fixed die fixing plate (2), the upper part of the pre-bending die assembly is arranged on the lower end face of the movable die top plate (3), a stretching anti-deformation component (4) is arranged in the pre-bending die assembly, the filling forming assembly is arranged on one side of the pre-bending die assembly, the upper part and the lower part of the filling forming assembly are respectively connected with the fixed die fixing plate (2) and the movable die top plate (3), and hydraulic filling forming components (12) are arranged on two sides of the filling forming assembly; the pre-press bending die assembly includes: the pre-bending lower die (5) and the pre-bending upper die (6), wherein the pre-bending lower die (5) is arranged on the fixed die fixing plate (2), and the pre-bending upper die (6) is arranged on the movable die top plate (3) and is symmetrically arranged with the pre-bending lower die (5);

The contact surface of the pre-bending lower die (5) and the pre-bending upper die (6) is an S-shaped curved surface which are matched with each other;

The inner sides of the contact surfaces of the pre-press bending lower die (5) and the pre-press bending upper die (6) are respectively provided with a pre-press forming groove (7) correspondingly;

The stretching anti-deformation members (4) are arranged in the pre-pressing forming groove (7) at certain intervals, and the stretching anti-deformation members (4) are hard metal block-shaped bulges;

The liquid filling pressure of the hydraulic filling member (12) is 0-30MPa.

2. A stainless steel tube cracking and creasing prevention forming die as claimed in claim 1, wherein said charge forming assembly comprises: filling lower mould (8) and filling upper mould (9), filling lower mould (8) set up on cover half fixed plate (2), filling upper mould (9) set up on the lower terminal surface of movable mould roof (3), and with filling lower mould (8) symmetrical arrangement.

3. The forming die for preventing cracking and wrinkling of stainless steel pipes according to claim 2, wherein forming shaping grooves (10) are symmetrically formed in the forming lower die (8) and the forming upper die (9) respectively, and the shape of the forming shaping grooves (10) is consistent with the external shape of the pipe to be processed.

4. A forming die for preventing cracking and wrinkling of stainless steel pipes according to claim 3, characterized in that a plurality of ejector pins (11) are arranged in the lower die (8).

5. The forming die for preventing cracking and wrinkling of stainless steel pipes according to claim 4, wherein a plurality of arc-shaped matching grooves are formed in the upper end face of the lower forming die (8), a plurality of arc-shaped protruding blocks are arranged on the lower end face of the upper forming die (9), and the arc-shaped protruding blocks are matched with the arc-shaped matching grooves.