CN108971302A - A kind of processing method of thin-wall part in-flanges - Google Patents

Abstract

The invention discloses a processing method for inner flanging of a thin-walled part, which is characterized in that two upper molds are taken, an arc-shaped flanging die is processed on the lower end surface of one upper mold, and the lower end surface of the other upper mold is processed Put out the shaping and flanging die; then put the thin-walled part blank to be stamped into the lower die, put the central mandrel in the thin-walled part blank, and put the cross-section L-shaped on both sides of the central mandrel respectively. The flanging mandrel; then put the upper mold with arc-shaped flanging die into the stamping machine, carry out the first flanging stamping on the thin-walled blank, and punch out circles on both sides of the thin-walled blank. Arc-shaped inward flanging; the upper mold with plastic flanging die is installed in the punching machine, and the second inward flanging stamping is carried out on the blank of the thin-walled part, and the circular arc-shaped inwards on both sides of the thin-walled part is turned inward The finished product is obtained by stamping into a straight shape and flanging inward; the advantage is that this method reduces the residual stress caused by uneven deformation, improves the forming accuracy of the workpiece, and is easy to disassemble the mold after stamping is completed.

Description

A processing method for inner flanging of thin-walled parts

technical field

The invention relates to stamping processing of thin-walled parts, in particular to a processing method for inner flanging of thin-walled parts.

Background technique

The thin-walled parts with inner flanging are mainly straight and annular, as shown in Figures 1 and 2, and the annular thin-walled part is one of the important components of the engine case, which makes the ring-shaped thin-walled part The machining accuracy has higher requirements. However, due to the complex structure and small wall thickness of the thin-walled parts with inner flanging, in the current processing method, the molds used are complicated, the disassembly and assembly are extremely time-consuming and laborious, and the forming accuracy is not high. There is residual stress, which is very prone to springback.

Contents of the invention

The technical problem to be solved by the present invention is to provide a processing method for inner flanging of thin-walled parts that can effectively improve forming precision, reduce residual stress, and facilitate disassembly and assembly of molds.

The technical solution adopted by the present invention to solve the above-mentioned technical problems is: a method for processing the inner flanging of thin-walled parts, comprising the following specific steps:

(1) Process the lower die on the lower die, and take two upper dies, process a curved flanging die on the lower end of one of the upper dies, and process a shaping flanging on the lower end of the other upper die Die;

(2) Put the thin-walled blank with a U-shaped cross-section to be punched into the lower die, and then put a central mandrel with a straight cross-section in the thin-walled blank. Put the flanging mandrel with L-shaped cross-section on both sides;

(3) Install the upper mold with arc-shaped flanging die into the punching machine, drive the upper mold to move down, and perform the first flanging stamping on the thin-walled blank, on both sides of the thin-walled blank Punch out the arc-shaped inner flanging;

(4) Install the upper mold with the shaping and flanging die into the punching machine, drive the upper mold to move down, and carry out the second flanging stamping on the blank of the thin-walled part, and make the arcs on both sides of the thin-walled part The shaped inner flanging is stamped into a straight inner flanging to obtain the finished product;

(5) After the stamping is completed, take out the central mandrel first, then take out the flanging mandrels one by one from the thin-walled parts, and finally take out the thin-walled parts with straight inner flanging from the lower mold.

Further, when the thin-walled part to be processed is straight, the specific operation process of the step (5) is: after the punching is completed, first take out the central mandrel, and then remove the flanging mandrel from the thin-walled part Take out one by one at the end or upper opening.

Further, when the thin-walled part to be processed is ring-shaped, in the step (2), put a ring-shaped turning core mold segment spliced by a plurality of L-shaped flanging core mold segments on the inner side of the central mandrel. The edge inner mandrel is put into the outer side of the central mandrel, which is a ring-shaped outer mandrel spliced by a plurality of L-shaped cross-sections of the outer mandrel. The outer arc of one of the outer mandrel segments The length is less than the length of the inner arc; the specific operation process of the step (5) is: after the stamping is completed, first take out the center mandrel, and then take out the flanging inner mandrel sections one by one from the upper opening of the thin-walled part, Then take out the flanging outer mandrel segments whose outer arc length is smaller than the inner arc length from the upper opening of the thin-walled part, and finally take out the remaining flanging outer mandrel segments one by one from the upper opening of the thin-walled part.

Further, the flanging section of the shaping and flanging die in the upper mold is inclined downward, and the upper end surface of the flanging mandrel is inclined upward and matches the flanging section in the shaping and flanging die, so that the shaping and flanging The concave die performs deformation stamping on the inner flanging of the thin-walled blank. After the stamping is completed, a straight inner flanging is obtained under the springback of the thin-walled part.

Further, the central mandrel has a draft slope.

Compared with the prior art, the advantage of the present invention is that the method adopts a central mandrel and a flanging mandrel independent of each other in the stamping process of the inner flanging, which facilitates the forming of thin-walled parts with inner flanging. The disassembly of the mold also reduces the difficulty of mold manufacturing; and when the inner flanging is stamped, a secondary stamping is used, firstly the inner flanging is stamped into an arc-shaped inner flanging, and then the arc-shaped inner flanging is shaped and flanged The concave die is stamped into a straight inner flanging, which separates the stamping flanging and shaping, and the separate setting of the shaping process greatly reduces the wrinkling and wall thickness reduction rate of thin-walled parts, making the deformation of the inner flanging Uniformity reduces the residual stress caused by uneven deformation and improves the forming accuracy of the workpiece.

Description of drawings

Fig. 1 is the structural representation of the thin-walled part with inner flanging of a straight strip;

Fig. 2 is the structural representation of the ring-shaped thin-walled part with inner flanging;

Fig. 3 is a schematic diagram of the state during the first inward flanging stamping according to Embodiment 1 of the present invention;

Fig. 4 is a schematic diagram of the state during the second inward flanging stamping according to Embodiment 1 of the present invention;

Fig. 5 is a schematic structural view of a shaping and flanging die according to Embodiment 1 of the present invention;

Fig. 6 is a schematic structural view of a flanging mandrel according to Embodiment 1 of the present invention;

Fig. 7 is a schematic diagram of the second embodiment of the present invention during the first inward flanging stamping;

Fig. 8 is a schematic diagram of the state of the second embodiment of the present invention during the second inward flanging stamping;

Fig. 9 is a schematic structural view of the flanging outer mandrel according to the second embodiment of the present invention.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

Embodiment 1: As shown in the figure, when the thin-walled part to be processed is straight, the processing method of its inner flanging includes the following specific steps:

(1), process the lower die 11 on the lower die 1, and take two upper dies 2-1, 2-2, and process an arc-shaped flanging die 21 on the lower end surface of one of the upper dies 2-1, Process the shaping flanging die 22 on the lower end surface of another upper mold 2-2, and the flanging section of the shaping flanging die 22 is downwardly inclined;

(2) Put the thin-walled blank 3 with a U-shaped cross-section to be stamped into the lower die 11, and then put the central mandrel 4 with a straight cross-section into the thin-walled blank 3, and press The both sides of central mandrel 4 are respectively put into cross-section as L-shaped flanging mandrel 5, and the upper end face of flanging mandrel 5 is inclined upwards and matches with the flanging section in the plastic flanging die 22;

(3) Install the upper mold 2-1 with the arc-shaped flanging die 21 in the punching machine, drive the upper mold 2-1 to move down, and perform the first flanging stamping on the thin-walled blank 3, Punch out arc-shaped inner flanges 31 on both sides of the thin-walled blank 3;

(4) Install the upper mold 2-2 with the shaping and flanging die 22 in the stamping machine, drive the upper mold 2-2 to move down, and carry out the second flanging stamping on the thin-walled blank 3, stamping At this time, the shaping and flanging die 22 carries out deformation stamping on the arc-shaped inner flanging 31 of the thin-walled part blank 3. After the stamping is completed, a straight inner flanging 32 is obtained under the springback of the thin-walled part, and the finished product;

(5) After the stamping is completed, take out the center mandrel 4 first, then take out the flanging mandrel 5 from the end or upper opening of the thin-walled part 3 one by one, and finally remove the inner mandrel 32 with a straight shape. The thin-walled part 3 is removed from the lower mold 1 .

Embodiment 2: As shown in the figure, when the thin-walled part to be processed is annular, the processing method of its inner flanging includes the following specific steps:

(1), process the lower die 11 on the lower die 1, and take two upper dies 2-1, 2-2, and process an arc-shaped flanging die 21 on the lower end surface of one of the upper dies 2-1, Process the shaping flanging die 22 on the lower end surface of another upper mold 2-2, and the flanging section of the shaping flanging die 22 is downwardly inclined;

(2) Put the thin-walled blank 3 with a U-shaped cross-section to be stamped into the lower die 11, and then put the central mandrel 4 with a straight cross-section into the thin-walled blank 3, and press The inner side of the central mandrel 4 is put into an annular flanging inner mandrel spliced by multi-section cross-sections of L-shaped flanging inner mandrel sections 6, and the outer side of the central mandrel 4 is put into a multi-section cross-section that is L-shaped. An annular flanging outer mandrel formed by splicing the flanging outer mandrel sections 7, wherein the length of the outer arc of one section of the flanging outer mandrel section 7 is less than the length of the inner arc, and the flanging inner mandrel and the flanging outer core The upper end face of mold is inclined upwards and matches with the flanging segment in the shaping flanging die 22;

(3) Install the upper mold 2-1 with the arc-shaped flanging die 21 in the punching machine, drive the upper mold 2-1 to move down, and perform the first flanging stamping on the thin-walled blank 3, Punch out arc-shaped inner flanges 31 on both sides of the thin-walled blank 3;

(4) Install the upper mold 2-2 with the shaping and flanging die 22 in the stamping machine, drive the upper mold 2-2 to move down, and carry out the second flanging stamping on the thin-walled blank 3, stamping At this time, the shaping and flanging die 22 carries out deformation stamping on the arc-shaped inner flanging 31 of the thin-walled part blank 3. After the stamping is completed, a straight inner flanging 32 is obtained under the springback of the thin-walled part, and the finished product;

(5) After the stamping is completed, take out the central mandrel 4 first, and then take out the flanging inner mandrel sections 6 from the upper opening of the thin-walled part 3 one by one, and then turn the outer arc length smaller than the inner arc length. The outer mandrel section 7 is taken out from the upper opening of the thin-walled part 3, and then the remaining flanged outer mandrel sections 7 are taken out one by one from the upper opening of the thin-walled part 3, and finally the The thin-walled part 3 of the edge 32 is removed from the lower mold 1 .

Claims (5)

1. a kind of processing method of thin-wall part in-flanges, it is characterised in that comprising the following specific steps

(1), lower cavity die is processed on lower mold, and takes two upper molds, is processed in the lower end surface of a wherein upper mold Arc flange cavity plate processes shaping flange cavity plate in the lower end surface of another upper mold；

(2), it is that U-shaped thin-wall part blank is put into lower cavity die by cross section to be punched, is then put into thin-wall part blank Cross section is the center core model of vertical bar shape, and at center, the two sides of core model are respectively put into the flange core model that cross section is L-type；

(3), in press machine be packed into have arc flange cavity plate upper mold, driving upper mold move down, to thin-wall part blank into Row first time in-flanges punching press stamps out arc-shaped in-flanges in the two sides of thin-wall part blank；

(4), in press machine be packed into have shaping flange cavity plate upper mold, driving upper mold move down, to thin-wall part blank into The arc-shaped in-flanges of thin-wall part two sides is struck out flat in-flanges, obtains finished product by second of in-flanges punching press of row；

(5), after the completion of punching press, center core model is first taken out, then takes out flange core model one by one from thin-wall part, will finally be had The thin-wall part of flat in-flanges takes out from lower mold.

2. a kind of processing method of thin-wall part in-flanges as described in claim 1, it is characterised in that: when thin-wall part to be processed is When vertical bar shaped, the specific operation process of the step (5) are as follows: after the completion of punching press, first take out center core model, then by flange Core model takes out one by one from the end of thin-wall part or upper opening.

3. a kind of processing method of thin-wall part in-flanges as described in claim 1, it is characterised in that: when thin-wall part to be processed is When annular, in the step (2), it is put on the inside of the core model of center and is spelled by the flange inner core mold segment that multistage cross section is L-type The flange inner core die for the annular being connected into is put on the outside of the core model of center and is spelled by multistage cross section for core model section outside the flange of L-type The outer core model of the flange for the annular being connected into, wherein the outer circle arc length of the outer core model section of one section of flange is less than inner circle arc length；Described The specific operation process of step (5) are as follows: after the completion of punching press, first take out center core model, then by flange inner core mold segment from thin-walled It is taken out one by one at the upper opening of part, then outer circle arc length is less than outside the flange of inner circle arc length core model section from the upper of thin-wall part Portion's opening is taken out, and finally takes out core model section outside remaining flange one by one from the upper opening of thin-wall part.

4. a kind of processing method of thin-wall part in-flanges as described in claim 1, it is characterised in that: the shaping in upper mold is turned over The flange section of edge die in tilting down, the upper surface of flange core model in inclination upwards and with the flange section in shaping flange cavity plate Match, so that shaping flange cavity plate carried out conversion press to the in-flanges of thin-wall part blank, after the completion of punching press, in thin-wall part Rebound effect under obtain flat in-flanges.

5. a kind of processing method of thin-wall part in-flanges as described in claim 1, it is characterised in that: on the center core model With draw taper.