A method for designing a forging die structure for controlling a displacement amount of a forged product

Abstract

The present application belongs to the field of forging, and relates to a method for designing a forging die structure for controlling the displacement of a forged piece. The method comprises the following steps: obtaining the length, width and thickness of the forged piece and the length and width of the die; setting the gap B2 between the special-shaped locking buckle and the gap B1 between the upper die and the lower die according to the maximum deflection of the forged piece, which leads to the limit displacement when the die is used; and setting the circular arc angle on the cross section of the special-shaped notch, which faces the direction of the forged piece, to constrain the deviation and deflection between the upper die and the lower die except along the longitudinal and lateral directions.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of forging, and relates to a forging die structure design method for controlling the displacement of a forged piece. BACKGROUND

[0002] At present, the forming of forged pieces is developing towards near net shape, but in the forming process of forged pieces, due to the influence of die machining, equipment error and the structure of forged pieces, the displacement between the upper die and the lower die often occurs in a certain direction in various forged pieces. The design allowance of the outer shape of precision forged pieces is greatly affected by the displacement of forged pieces, especially for structure forged pieces with lateral force. There is a regular displacement between the upper die and the lower die, and the displacement will further increase with the use of the die, which easily causes the forming quality of forged pieces to decrease or even be scrapped. For rotary forged pieces, there is uncertainty in the displacement, and for structure forged pieces, there is displacement and deflection. In this case, guide pillars are used for guidance or the accuracy of the equipment is relied on. For forged pieces with lateral force, the service life of the guide pillars and the die is usually short. Closed die forging (no flash die forging) is usually used to produce precision forged pieces with small allowance, but this method has high requirements for the die machining, and the surface and accuracy of the die are required to be high. When the distribution of the flash of the forged piece is uneven, the risk of the forming of the forged piece increases, and the vertical flash aggravates the demolding difficulty, which greatly affects the continuity of production and the service life of the die. SUMMARY

[0003] The technical problem to be solved by the present application is to provide a forging die structure design method for controlling the displacement of a forged piece, which can effectively reduce the displacement of the forged piece, solve the problem of damage of the closed die during installation and use, relieve the demolding difficulty, control the uniformity of the flash, improve the continuity of production and prolong the service life of the die.

[0004] TECHNICAL SCHEME

[0005] A forging die structure design method for controlling the displacement of a forged piece, the forging die structure comprising: an upper die and a lower die; a plurality of non-continuous locking ports are arranged on the upper die along the outer shape of the cavity; corresponding locking buckles are arranged at the corresponding positions of the lower die; the locking buckles and the locking ports form a locking buckle structure; the outer side wall of the locking port extends downward to form a parting surface; the inner wall of the outer side wall is divided into a straight wall working section and a lower end inclined surface guide section; the locking buckle is a boss extending upward to form a parting surface; a special-shaped notch is formed in the upper end surface of the boss downward; the bottom surface of the special-shaped notch is lower than the parting surface; the side wall of the special-shaped notch is divided into an upper end inclined surface guide section and a straight wall working section; when the upper end inclined surface guide section and the lower end inclined surface guide section of the locking buckle are aligned with each other, the outer side wall of the locking port extends into the special-shaped notch, and the boss enters the locking port; the method comprises the following steps:

[0006] obtaining the length, width and thickness of the forged piece and the length and width of the die;

[0007] According to the maximum deflection of the forging allowed by the die, the profiled locking gap B2 and the gap B1 between the upper and lower dies are set;

[0008] The circular arc angle on the cross section of the profiled gap towards the forging direction is set to constrain the deflection and deflection between the upper and lower dies except along the longitudinal and transverse directions.

[0009] The relationship between the profiled locking gap B2 and the gap B1 between the upper and lower dies is:

[0010] ,

[0011] Wherein, B2 is the profiled locking gap value; B1 is the upper and lower die gap value of the forging; L is the die length; l is the forging length; B is the die width; b is the forging width; K is the coefficient, the value is 0.2-0.5.

[0012] When the length-width ratio of the die profile is smaller, the value of K is closer to 0.5, and when the length-width ratio of the die profile is larger, the value of K is closer to 0.2.

[0013] The included angle between the inclined lead-in section of the lower die and the straight wall working section of the lower die is 10-20 degrees, the length H1 of the inclined lead-in section of the lower die is max (0.2H, 20mm), and H is the thickness of the forging; The height L2 of the straight wall working section of the lower die is ≥ (0.3-0.4) H+H1.

[0014] The straight wall working section L1 of the upper die is 10-40mm.

[0015] The circular arc angle on the cross section of the profiled gap towards the forging direction is set, including:

[0016] The length and width of the profiled gap cross section are transitioned by 1 / 4 circular arc.

[0017] The radius of the circular arc is the minimum value between 1 / 2 length and 1 / 2 width of the profiled gap cross section.

[0018] A computer readable storage medium, having stored thereon a computer program, the computer program being executed by a processor to implement the method as described above.

[0019] Beneficial effect: (advantages) the present application provides a kind of controllable forging displacement amount of forging die structure design method, for different typical forging structure, by reasonably setting the shape of special-shaped lock and special-shaped, the gap between upper and lower die, the purpose of controlling the displacement amount of forging can be realized by controlling the displacement between upper and lower die.By the design of special-shaped lock structure, on the one hand, it can prevent the collision and damage of small gap die during installation and use, improve the service life of die, on the other hand, through the design of special-shaped structure, enough strength can be provided for the displacement force of forging in any direction, which avoids the main guide column of die, which cannot provide enough anti-displacement capacity, also avoids the general lock, only participates in the displacement correction of forging at the end of forming, and only provides longitudinal and transverse anti-error.By the cooperation of the inclined surface lead-in section and the straight wall section, and the use of straight edge and arc, the displacement force from the forming process of forging in any direction from the forging can be offset, by calculation, the gap between upper and lower die and special-shaped lock can prevent the damage of die during installation and use, improve the service life of die, and in the use process, the forgings meeting the displacement amount requirement can be obtained. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is a kind of control forging displacement amount of forging die structure structure diagram.

[0021] Figure 2 It is a cross section diagram of forging die structure.

[0022] Figure 3 It is a cross section diagram of special-shaped lock. DETAILED DESCRIPTION

[0023] The present application provides a kind of control forging displacement amount of forging die structure design method, which is aimed at Figure 1 The control forging displacement amount of forging die structure design parameter, as shown in Figures 2-3 The forging die structure includes: upper die, lower die; a plurality of lock openings are arranged discontinuously on the upper die along the outer shape of the cavity, and the corresponding lock is arranged at the corresponding position of the lower die, and the lock and the lock opening form a lock structure; the outer side wall of the lock opening extends downward to the parting surface, and the inner wall of the outer side wall is divided into a straight wall working section and a slope lead-in section at the lower end; the lock is a boss extending upward to the parting surface, and the upper end surface of the boss is provided with a special-shaped notch downward, and the bottom surface of the special-shaped notch is lower than the parting surface; the side wall of the special-shaped notch is divided into a slope lead-in section at the upper end and a straight wall working section; when the lock descends with the upper die, the slope lead-in section at the upper end and the slope lead-in section at the lower end are aligned with each other, the outer side wall of the lock opening extends into the special-shaped notch, and the boss enters the lock opening.

[0024] The method comprises:

[0025] There are many reasons for the displacement or deflection of the forgings, the main reasons are that there is a lack of proper constraint between the upper die and the lower die during the forming process of the forgings, the guide column mainly plays a guiding role, and the ordinary lock only participates in the correction of the displacement of the forgings in the late stage of the whole deformation process, at which time the mold has already relatively moved or deflected.

[0026] In order to prevent the displacement of the mold, the design constraint is mainly carried out in two directions, one is to provide guidance and displacement control of the working section in the height direction of the special-shaped lock of the mold, and the other is to prevent the relative rotation of the upper and lower molds in the plane of the mold.

[0027] The calculation in the height direction of the special-shaped lock is:

[0028] The thickness of the forging is H, L1 is the length of the mold cavity during the forming of the forging, which is 10-40mm;

[0029] The special-shaped lock of the upper and lower molds is composed of a beveled lead-in section and a straight wall working section, the design purpose is that the special-shaped lock is first contacted during the installation and closure of the mold and the working process, and then the upper and lower molds of the mold are contacted with the contact part of the forging, until the whole process of the forging forming.

[0030] The angle between the beveled lead-in section and the straight wall section is 10-20 degrees, the length H1 of the beveled lead-in section is max (0.2H, 20mm), for small forgings, the length of this part is shorter, and under normal circumstances, it should not be less than 20mm, otherwise it cannot play the role of mutual lead-in of the two bevels, for medium and large forgings, this part should meet about 20% of the thickness of the forging; the height L2 of the straight wall working section is ≥ (0.3-0.5) H+H1, the height of the straight wall working section provides displacement control for the upper and lower molds during the whole deformation process, according to the last deformation characteristics of the existing aviation forging material, combined with the thickness of the forging, i.e. the deformation direction, the height requirement L2 of the straight wall working section is proposed, the purpose is to meet the displacement control range of the upper and lower molds during the whole deformation process.

[0031] The calculation in the horizontal plane of the special-shaped lock is:

[0032] The displacement or deflection of the forgings in the horizontal direction is determined by the displacement and deflection of the upper and lower molds, so the displacement and deflection of the forgings can be controlled by calculating the possible displacement and deflection of the mold. In general, the displacement and deflection of the mold occur simultaneously, and in different directions, there is also a different degree of displacement during the whole process of the forging forming. In addition, for the deformation process of the upper and lower molds which is not constrained in the deformation direction, the mold gap in one direction is greater than that in any other part, even twice the required displacement of the forgings.

[0033] For the above reasons, the model can be simplified first, assuming that the forging around the mold center rotation, the maximum value of the forging along the length of the offset B1 and the maximum value of the mold along the length of the offset B2, with the length of the half of the forging and the length of the half of the mold is proportional to the positive, that is:

[0034]

[0035] For the long rod type mold, the numerical value approaches 1, and it cannot completely control the mold gap, and the model needs to be further optimized, that is, the farthest place in the length direction of the forging is taken as the rotation base point, and the maximum deflection distance B1 that may occur should meet the requirements of the forging offset, and the relationship between the length of the mold should also meet

[0036]

[0037] That is,

[0038] In order to improve the safety of the mold, the safety factor K is introduced, and the range is 0.2-0.4. When the length-width ratio of the mold shape is smaller, K is close to 0.5, and when the length-width ratio of the mold shape is larger, K is close to 0.2.

[0039] Accordingly, the forging should meet this rule in width and length, and should meet the respective conditions.

[0040] That is, ,

[0041] For example:

[0042] A forging is a typical long rod forging, and the forging size is 1200x300x100mm. The mold size is 1800x800x450mm, and the forging offset requirement is less than or equal to 3mm.

[0043] That is, B1 is 3mm, the length-width ratio of the forging is large, K is 0.3, the gap value B2 of the mold special-shaped lock in the length direction should be less than 1.12mm, and the gap value of the special-shaped lock in the width direction should be less than 1.65mm. The gap value B1 between the convex and concave dies can be taken as 1.6m;

[0044] The length H1 of the inclined surface of the lower die is 20mm, and the slope is 15 degrees;

[0045] The height L2 of the straight wall working section of the lower die is 70mm;

[0046] The cross section of the special-shaped notch adopts circular arc transition.

Claims

1. A method of designing a forging die structure for controlling a shift amount of a forged product, characterized by, The forging die structure comprises: an upper die and a lower die; a plurality of discontinuous locking notches are arranged on the upper die along the shape of the cavity outwardly, and corresponding locking catches are arranged at the corresponding positions of the lower die, the locking catches and the locking notches form a locking catch structure; the outer sidewall of the locking notch extends downward to a parting surface, the inner wall of the outer sidewall is divided into a straight wall working section and a beveled lead-in section at the lower end; the locking catch is a boss extending upward to the parting surface, a special-shaped notch is formed on the upper end surface of the boss downwardly, and the bottom surface of the special-shaped notch is lower than the parting surface; the sidewall of the special-shaped notch is divided into a beveled lead-in section at the upper end and a straight wall working section; when the upper die moves downward, the beveled lead-in section at the upper end and the beveled lead-in section at the lower end are aligned with each other, the outer sidewall of the locking notch extends into the special-shaped notch, and the boss enters the locking notch; the method comprises: obtaining the length, width and thickness of the forging and the length, width and thickness of the die; setting the special-shaped locking catch gap B2 and the gap B1 between the upper and lower dies according to the maximum deflection of the forging allowed by the die, and the relationship between the special-shaped locking catch gap B2 and the gap B1 between the upper and lower dies is: , wherein B2 is the special-shaped locking catch gap value; B1 is the gap value between the upper and lower dies of the forging; L is the length of the die; l is the length of the forging; B is the width of the die; b is the width of the forging; K is a coefficient, and the value is 0.2-0.5; setting the circular arc angle on the cross section of the special-shaped notch towards the forging direction to constrain the offset and deflection between the upper die and the lower die except along the longitudinal and transverse directions.

2. The method of claim 1, wherein, When the length-width ratio of the die shape is smaller, the value of K is closer to 0.5, and when the length-width ratio of the die is larger, the value of K is closer to 0.

2.

3. The method of claim 1, wherein, The included angle between the beveled lead-in section of the lower die and the straight wall working section of the lower die is 10-20 degrees, the length H1 of the beveled lead-in section of the lower die is max (0.2H, 20mm), and H is the thickness of the forging; the height L2 of the straight wall working section of the lower die is (0.3-0.4) H+H1.

4. The method of claim 1, wherein, The straight wall working section L1 of the upper die is 10-40mm.

5. The method of claim 1, wherein, Setting the circular arc angle on the cross section of the special-shaped notch towards the forging direction, comprising: the length and width of the cross section of the special-shaped notch are transitioned by 1 / 4 circular arc.

6. The method of claim 5, wherein, The radius of the circular arc is the minimum value between 1 / 2 length and 1 / 2 width of the cross section of the special-shaped notch.

7. A computer-readable storage medium having stored thereon a computer program, characterized in that The computer program is executed by the processor to realize the method of any one of claims 1-6.

Images