阅读说明：本技术 一种大型法兰的锻造用切肩刀及锻造方法 (Shoulder cutter for forging large flange and forging method ) 是由 黄贵林 张文博 王周建 徐学民 侯会凯 于 2021-09-18 设计创作，主要内容包括：本发明公开一种大型法兰的锻造用切肩刀及锻造方法,所述切肩刀为圆环型结构,所述切肩刀包括夹合部、磨削部、内环壁和外环壁,所述内环壁和外环壁均倾斜设置,所述磨削部设置在所述内环壁和外环壁之间,所述磨削部用于对法兰进行环形切肩,所述夹合部设置在内环壁和外环壁之间,所述夹合部用于与机床固定,所述夹合部和磨削部分别设置在所述切肩刀的上下两侧,且从夹合部到磨削部的方向上,所述内环壁和外环壁的间距逐渐减小。通过切肩刀在坯料上环切出一个环形凹槽,通过环形凹槽与漏盘定位,能够对坯料在漏盘上进行圆周方向上的定位,每一次锤击时坯料和漏盘、漏盘和下砧之间均能够保证稳定,能够避免加工过程导致法兰偏心的问题。(The invention discloses a shoulder cutting knife for forging a large flange and a forging method, wherein the shoulder cutting knife is of a circular structure and comprises a clamping part, a grinding part, an inner ring wall and an outer ring wall, the inner ring wall and the outer ring wall are both obliquely arranged, the grinding part is arranged between the inner ring wall and the outer ring wall, the grinding part is used for carrying out annular shoulder cutting on the flange, the clamping part is arranged between the inner ring wall and the outer ring wall and is used for being fixed with a machine tool, the clamping part and the grinding part are respectively arranged on the upper side and the lower side of the shoulder cutting knife, and in the direction from the clamping part to the grinding part, the distance between the inner ring wall and the outer ring wall is gradually reduced. An annular groove is cut out on the blank by the shoulder cutter, the blank can be positioned on the drain pan in the circumferential direction by the positioning of the annular groove and the drain pan, the blank and the drain pan, the drain pan and the lower anvil can be stably ensured during each hammering, and the problem that the flange is eccentric in the machining process can be avoided.)

1. A shoulder cutter for forging a large flange and a forging method are characterized in that the shoulder cutter (1) is of a circular ring type structure, the shoulder cutting knife (1) comprises a clamping part (12), a grinding part (14), an inner ring wall (11) and an outer ring wall (13), the inner ring wall (11) and the outer ring wall (13) are both obliquely arranged, the grinding part (14) is arranged between the inner ring wall (11) and the outer ring wall (13), the grinding part (14) is used for carrying out annular shoulder cutting on the flange (2), the clamping part (12) is arranged between the inner annular wall (11) and the outer annular wall (13), the clamping part (12) is used for being fixed with a machine tool, the clamping part (12) and the grinding part (14) are respectively arranged at the upper side and the lower side of the shoulder cutter (1), and the distance between the inner ring wall (11) and the outer ring wall (13) is gradually reduced from the clamping part (12) to the grinding part (14).

2. The shoulder cutter for forging a large flange as claimed in claim 1, wherein the inner annular wall (11) is a circular truncated cone-shaped arc surface, and the caliber of the inner annular wall (11) is gradually increased along a direction from the nip portion (12) to the grinding portion (14).

3. The shoulder cutter for forging a large flange as claimed in claim 1, wherein the outer annular wall (13) is a circular truncated cone-shaped arc surface, and the diameter of the outer annular wall (13) is gradually reduced in a direction from the nip portion (12) to the grinding portion (14).

4. A large flange forging shoulder cutter as claimed in claim 3, wherein the included angle between the inner annular wall (11) and the outer annular wall (13) is 40-60 °.

5. A large flange forging shoulder cutter as claimed in claim 3, wherein the included angle between the inner ring wall (11) and the vertical center line of the shoulder cutter (1) is 5-15 °.

6. A large flange forging shoulder cutter as claimed in claim 3, wherein the angle between the outer annular wall (13) and the vertical center line of the shoulder cutter (1) is 40-50 °.

7. A large flange forging shoulder cutter as claimed in claim 3, wherein the vertical height of the inner ring wall (11) is greater than 2/3 of the step height of the flange (2).

8. A forging method of a large flange, characterized in that the shoulder cutter (1) according to any one of claims 1 to 7 is applied, and further comprising the steps of:

s1: calculating the size of a required boss according to the large flange (2) to be forged;

s2: obtaining a shoulder cutter (1) with the size corresponding to the boss;

s3: placing the shoulder cutting knife (1) and the blank (3) on the lower anvil surface of the forging hammer, and performing circular cutting on the blank (3) through the shoulder cutting knife (1) until a circular fixing groove is cut;

s4: and (3) placing the processed blank (3) on a drain pan, forging by a upsetting and extruding composite method, and aligning and fixing the annular fixing groove and the drain pan.

9. The forging method of a large flange according to claim 8, wherein before step S1, the forging method further comprises pre-upsetting the blank (3), wherein the pre-upset height H is related to the total forging height H as follows: h is (1.15-1.25) H.

10. A forging method of a large flange according to claim 8, wherein the boss diameter in step S1 is 5mm smaller than the tip plate diameter at most.

Technical Field

The invention relates to the field of universal hot working, in particular to a shoulder cutter for forging a large flange and a forging method.

Background

The flange product is one of the most widely applied parts in the mechanical manufacturing industry, and has the process characteristics that: the eccentric gear is composed of two concentric cylinders with different sizes and larger volume difference, is particularly used for heavy-duty transmission gears, has larger mass and smaller batch, is usually produced by free forging in order to save raw materials and reduce processing cost, has higher requirement on the coaxiality, but is very easy to generate eccentric condition in the actual production process and is difficult to correct and repair.

The forging scheme adopted by the flange in the past production comprises two forging schemes, namely 1, directly upsetting and forging the flange on a drain pan; 2. upsetting the blank to a certain height, and then placing the blank on a bushing for forging by a upsetting and extruding composite method. Practice proves that the two forging schemes are easy to generate eccentric defects, and the maximum central offset reaches over 25mm, so that products are scrapped. And the upsetting phenomenon is continuously corrected when upsetting is needed, the upsetting can be finished for two times, the forging speed is low, the production efficiency is low, the shift yield can only reach 8-10 pieces, the product quality is extremely unstable, and the repair rate is as high as 50%. In the second scheme, the phenomenon that the small column is not fully filled exists.

The phenomenon that the two schemes in the past simultaneously generate eccentric defects is analyzed. The first scheme is that the eccentric defect is mainly caused by the fact that excessive and overhigh blanks are stacked on the upper portion of the drain pan, if a 280mm round steel blank is used, the upsetting height of the upper portion of the drain pan is 740mm, the upsetting height-diameter ratio reaches 2.65, and upsetting deflection is easy to occur. The blank which is upset and inclined needs to be corrected while upsetting, the forging manipulator cannot be operated flexibly like manual operation during correction, the correction operation difficulty is high, and the blank cannot be exactly positioned in the hitting center of the forging hammer during each hammering. The second scheme is that the main reason of eccentricity is that although the height-diameter ratio of the upsetting deformation part is reduced after the blank is subjected to once upsetting deformation, the blank cannot be positioned in the circumferential direction when being placed on the drain pan, and the blank jumps from the drain pan to the lower anvil when being hammered every time. Therefore, there is a need for a shoulder cutter for forging a large flange and a forging method.

Disclosure of Invention

The invention aims to provide a shoulder cutter for forging a large flange and a forging method.

The embodiment of the invention is realized by the following steps:

the shoulder cutting knife is of a circular structure and comprises a clamping portion, a grinding portion, an inner ring wall and an outer ring wall, wherein the inner ring wall and the outer ring wall are obliquely arranged, the grinding portion is arranged between the inner ring wall and the outer ring wall and used for performing annular shoulder cutting on a flange, the clamping portion is arranged between the inner ring wall and the outer ring wall and used for being fixed with a machine tool, the clamping portion and the grinding portion are respectively arranged on the upper side and the lower side of the shoulder cutting knife, and the distance between the inner ring wall and the outer ring wall is gradually reduced in the direction from the clamping portion to the grinding portion. An annular groove is cut out on the blank by the shoulder cutter, the blank can be positioned on the drain pan in the circumferential direction by the positioning of the annular groove and the drain pan, the blank and the drain pan, the drain pan and the lower anvil can be stably ensured during each hammering, and the problem that the flange is eccentric in the machining process can be avoided.

Preferably, the inner annular wall is a truncated cone-shaped arc surface, and the caliber of the inner annular wall gradually increases along a direction from the clamping portion to the grinding portion. The method can ensure that the workpiece can be smoothly taken out after the shoulder cutting procedure is finished and the forge piece can not form folding defects at the step in the forging process.

Preferably, the outer annular wall is a truncated cone-shaped arc surface, and the caliber of the outer annular wall gradually decreases along a direction from the clamping portion to the grinding portion.

Preferably, the included angle between the inner annular wall and the outer annular wall is 40-60 degrees. Preferably 55.

Preferably, the included angle between the inner ring wall and the vertical center line of the shoulder cutter is 5-15 degrees. Preferably 10.

Preferably, the included angle between the outer annular wall and the vertical center line of the shoulder cutter is 40-50 degrees. Preferably 45 deg. is selected.

Preferably, the vertical height of the inner annular wall is greater than 2/3, the height of the flange step.

The forging method of the large flange is further provided, the shoulder cutter is applied, and the forging method further comprises the following steps:

s1: calculating the size of a required boss according to a large flange to be forged;

s2: obtaining a shoulder cutter with the size corresponding to the boss;

s3: placing the shoulder cutter and the blank on the lower anvil surface of the forging hammer, and performing circular cutting on the blank by the shoulder cutter until a circular fixing groove is cut;

s4: and (3) placing the processed blank on a drain pan, forging by a upsetting and extruding composite method, and aligning and fixing the annular fixing groove and the drain pan.

Preferably, before step S1, pre-upsetting the blank is further included, and the pre-upsetting height H is related to the total forging height H as follows: h is (1.15-1.25) H. The pre-upsetting height is too high, the diameter of the blank is not large enough during shoulder cutting, the shoulder cutting process is not easy to be carried out, and the defects of deviation cutting, skewness cutting and folding are easy to generate. If the upsetting height is kept too low, although the requirement of shoulder cutting operation is ensured, when the blank is placed on a drain pan for forging, the disk part of the flange is subjected to free upsetting, the boss part of the flange is subjected to positive extrusion deformation, and when the height of the flange disk part is upset to the nominal size of the forging, the boss part is still not filled due to insufficient extrusion deformation, so that the total height size of the forging exceeds the lower difference.

Preferably, the boss diameter in step S1 is at most 5mm smaller than the tip disk diameter.

Due to the adoption of the technical scheme, the invention has the beneficial effects that: the shoulder cutting tool is of a circular structure and comprises a clamping part, a grinding part, an inner ring wall and an outer ring wall, wherein the inner ring wall and the outer ring wall are obliquely arranged, the grinding part is arranged between the inner ring wall and the outer ring wall, the grinding part is used for carrying out annular shoulder cutting on a flange, the clamping part is arranged between the inner ring wall and the outer ring wall and is used for being fixed with a machine tool, the clamping part and the grinding part are respectively arranged on the upper side and the lower side of the shoulder cutting tool, and the distance between the inner ring wall and the outer ring wall is gradually reduced from the clamping part to the grinding part. An annular groove is cut out on the blank by the shoulder cutter, the blank can be positioned on the drain pan in the circumferential direction by the positioning of the annular groove and the drain pan, the blank and the drain pan, the drain pan and the lower anvil can be stably ensured during each hammering, and the problem that the flange is eccentric in the machining process can be avoided.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a schematic view of the structure of the shoulder cutter of the present invention;

FIG. 2 is a schematic view of the flange construction of the present invention;

fig. 3 is a schematic view of the blank construction of the present invention.

Description of specific element symbols: 1-shoulder cutter, 2-flange, 3-blank, 11-inner ring wall, 12-clamping part, 13-outer ring wall and 14-grinding part.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. The following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1: referring to fig. 1 to 3, in the present embodiment, the shoulder cutting tool 1 for forging a large flange has a circular structure, the shoulder cutting tool 1 includes a clamping portion 12, a grinding portion 14, an inner annular wall 11 and an outer annular wall 13, the inner annular wall 11 and the outer annular wall 13 are both disposed in an inclined manner, the grinding portion 14 is disposed between the inner annular wall 11 and the outer annular wall 13, the grinding portion 14 is configured to perform circular shoulder cutting on the flange 2, the clamping portion 12 is disposed between the inner annular wall 11 and the outer annular wall 13, the clamping portion 12 is configured to be fixed to a machine tool, the clamping portion 12 and the grinding portion 14 are respectively disposed on upper and lower sides of the shoulder cutting tool 1, and a distance between the inner annular wall 11 and the outer annular wall 13 gradually decreases in a direction from the clamping portion 12 to the grinding portion 14. An annular groove is cut out on the blank 3 through the shoulder cutting knife 1, the blank 3 can be positioned on the drain pan in the circumferential direction through the annular groove and the drain pan, the blank 3 and the drain pan, the drain pan and the lower anvil can be stably ensured during hammering each time, and the problem that the flange 2 is eccentric in the machining process can be avoided.

Example 2: referring to fig. 1 to 3, the inner annular wall 11 of the present embodiment is a circular truncated cone-shaped arc surface, and the caliber of the inner annular wall 11 gradually increases along a direction from the clamping portion 12 to the grinding portion 14. The method can ensure that the workpiece can be smoothly taken out after the shoulder cutting procedure is finished and the forge piece can not form folding defects at the step in the forging process. The outer annular wall 13 of the present embodiment is a circular truncated cone-shaped arc surface, and the diameter of the outer annular wall 13 gradually decreases in the direction from the nip portion 12 to the grinding portion 14. The angle between the inner annular wall 11 and the outer annular wall 13 in this embodiment is 40-60 °. Preferably 55 degrees, the included angle between the inner annular wall 11 and the vertical central line of the shoulder cutter 1 is 5-15 degrees. Preferably 10. The angle between the outer annular wall 13 and the vertical center line of the shoulder cutter 1 is 40-50 degrees in the embodiment. Preferably 45 deg. is selected. The vertical height of the inner annular wall 11 of this embodiment is greater than 2/3, the step height of the flange 2.

Example 3: referring to fig. 1 to 3, the present embodiment further provides a method for forging a large flange, applying the above-mentioned shoulder cutting tool 1, further including the following steps: s1: calculating the size of a required boss according to the large flange 2 required to be forged; s2: obtaining a shoulder cutter 1 with the size corresponding to the boss; s3: placing the shoulder cutting knife 1 and the blank 3 on the lower anvil surface of the forging hammer, and performing circular cutting on the blank 3 through the shoulder cutting knife 1 until a circular fixing groove is cut; s4: and (3) placing the processed blank 3 on a drain pan, forging by a upsetting and extruding composite method, and aligning and fixing the annular fixing groove and the drain pan. The embodiment further includes, before step S1, pre-upsetting the blank 3, wherein the pre-upsetting height H is related to the total forging height H as follows: h is (1.15-1.25) H. The pre-upsetting height is too high, the diameter of the blank 3 is not large enough during shoulder cutting, the shoulder cutting process is not easy to be carried out, and the defects of deviation cutting, deviation cutting and folding are easy to generate. If the upsetting height is kept too low, although the requirement of shoulder cutting operation is ensured, when the blank 3 is placed on a drain pan for forging, the disk part of the flange 2 is free upsetting, the boss part of the flange 2 is positive extrusion deformation, and when the disk part height of the flange 2 is upset to the nominal size of the forging, the boss part is still not filled due to insufficient extrusion deformation, so that the total height size of the forging exceeds the lower limit. The boss diameter in step S1 of the present embodiment is 5mm smaller than the tip disk diameter at most.

Example 4: referring to fig. 1 to 3, the flange 2 product of the present embodiment is a driven gear, the forged product has a mass of 390kg, and is composed of two concentric cylinders with different sizes, the mass of the large cylinder is 354kg, the mass of the small cylinder is 36kg, the volumes of the large cylinder and the small cylinder are very different, and the ratio of the masses is close to 10. The method of the embodiment not only reduces the height-diameter ratio of the upsetting deformation part, but also can accurately position the upsetting deformation part in the circumferential direction after the upsetting deformation part is placed on the drain pan, so that the runout between the blank 3 and the drain pan and between the drain pan and the lower anvil is reduced. Finally, determining that a circular shoulder cutting process is added after the blank 3 is upset to a certain height, and cutting a concentric cylinder of 280mm on one end face of the upset blank 3 by using a circular shoulder cutter 1. The purpose of the annular shoulder cutting is to cut a boss of 280mm from the blank 3 after pre-upsetting, the boss is concentric with the upset blank 3 as much as possible, and the diameter of the boss can be less than 5mm of the diameter of the drain pan. The shoulder cutting depth refers to that of a step shaft product, and is equal to about 2/3 of the height of the step. The annular shoulder cutting knife 1 has the appearance design that the annular shoulder cutting knife can be smoothly taken out of a workpiece after the shoulder cutting procedure is completed, and the forge piece cannot form a folding defect at a step in the forging process. For this purpose, the inner inclination is 10 degrees, the outer inclination is 45 degrees, and the inner inclination and the outer inclination are connected by a large arc. The special annular shoulder cutting knife 1 is designed and manufactured by deeply analyzing the reasons for generating the eccentric defects of the large-scale flange 2 forging and adjusting and improving the original process. The method is verified by actual production, and the eccentric defect of the large-scale flange 2 forging can be completely controlled within the range of the technical requirement. The production efficiency is improved by two times, the fire number is reduced to 1 fire number, the rejection rate and the return rate are 0, and the one-time acceptance rate of the product is improved to 100 percent.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.