阅读说明：本技术 带外岛屿凸台的异型薄壁机匣环锻件轧制方法 (Rolling method of special-shaped thin-wall casing ring forging with external island boss ) 是由 兰箭 华林 毛华杰 钱东升 邓加东 于 2021-07-29 设计创作，主要内容包括：本发明公开了一种带外岛屿凸台的异型薄壁机匣环锻件轧制方法,目标异型薄壁机匣环锻件的一部为近矩形截面环、另一部为近锥筒环且带有外岛屿凸台,先下料镦粗冲孔得到近矩形截面环坯,然后单边扩口得到厚壁异型截面环坯,然后轧制得到异型截面环坯,然后先粗轧制得到带内回转凸台的异型截面环坯,内回转凸台为一圈位于近锥筒环内侧对应外岛屿凸台高度位置处的环状突起,再整形提高带内回转凸台的异型截面环坯的圆度精度,最后精轧,近净成形异型薄壁机匣环锻件外表面并将内回转凸台体积转移到外表面得到外岛屿凸台。本发明近净成形异型薄壁机匣环锻件外表面并在外表面得到外岛屿凸台,能保证外直径和外岛屿凸台精度,机加工余量低。(The invention discloses a rolling method of a special-shaped thin-wall casing ring forging with an outer island boss, wherein one part of a target special-shaped thin-wall casing ring forging is a nearly rectangular section ring, the other part of the target special-shaped thin-wall casing ring forging is a nearly conical cylinder ring and is provided with the outer island boss, a nearly rectangular section ring blank is obtained by blanking, upsetting and punching, then a thick-wall special-shaped section ring blank is obtained by single-side flaring, then a special-shaped section ring blank is obtained by rolling, then a special-shaped section ring blank with an inner rotary boss is obtained by rough rolling, the inner rotary boss is a ring-shaped protrusion which is positioned at the inner side of the nearly conical cylinder ring and corresponds to the height position of the outer island boss, then the roundness precision of the special-shaped section ring blank with the inner rotary boss is improved by reshaping, finally, the outer surface of the special-shaped thin-wall casing ring forging is formed by near-net forming, and the volume of the inner rotary boss is transferred to the outer surface to obtain the outer island boss. The method for near-net forming the outer surface of the special-shaped thin-wall casing ring forging and obtaining the outer island boss on the outer surface can ensure the outer diameter and the accuracy of the outer island boss and has low machining allowance.)

1. The rolling method of the special-shaped thin-wall casing ring forging with the island boss is characterized by comprising the following steps of: one part of the target special-shaped thin-wall casing ring forging is a near-rectangular section ring, the other part of the target special-shaped thin-wall casing ring forging is a near-conical cylinder ring and is provided with an outer island boss, a near-rectangular section ring blank is obtained by blanking, upsetting and punching, then a thick-wall special-shaped section ring blank is obtained by single-side flaring, then the special-shaped section ring blank is obtained by rolling, then the special-shaped section ring blank with an inner rotary boss is obtained by rough rolling, the inner rotary boss is a ring-shaped protrusion which is positioned at the position, corresponding to the height position of the outer island boss, of the inner side of the near-conical cylinder ring, the roundness precision of the special-shaped section ring blank with the inner rotary boss is improved by reshaping, and finally, the outer surface of the special-shaped thin-wall casing ring forging is formed by near-finish rolling, and the volume of the inner rotary boss is transferred to the outer surface to obtain the outer island boss;

the adopted finish rolling die comprises a driving roller, a core roller and a combined cover die which can rotate actively, wherein the driving roller or the core roller can feed linearly; the combined cover die comprises a cover die and a plurality of split dies which can be enclosed into a circle, the whole circle of split dies are detachably matched, inserted and installed on a conical surface of an inner ring of the cover die, an outer ring of the cover die is in contact with the driving roller and can be driven to rotate by the driving roller, the inner surface of the whole circle of split dies is matched with the outer surface of the special-shaped thin-wall casing ring forging, the outer surface of a working part of the core die is matched with the inner surface of the special-shaped thin-wall casing ring forging, the split dies have a structure for axially limiting a ring blank, and grooves matched with bosses of an outer island are formed in corresponding positions of the inner surface.

2. The rolling method of the special-shaped thin-walled casing ring forging with island bosses of claim 1, wherein: the target size of each stage is determined by backward pushing the special-shaped thin-wall casing part with the island boss, the size of the special-shaped thin-wall casing ring forging with the island boss is obtained according to the size of the special-shaped thin-wall casing part with the island boss and the forging allowance on two sides, the outer island boss of the special-shaped thin-wall casing ring forging with the island boss is removed, the volume sum of all the outer island bosses is multiplied by several times and arranged on the inner surface of the corresponding height position to obtain the size of the special-shaped section ring blank with the rotary boss, the size of the special-shaped section ring blank with the rotary boss is obtained by estimation according to the selected rolling ratio range and the principle that the axial sectional areas are equal, the size of the thick-wall special-shaped section ring blank is obtained by estimation according to the selected rolling ratio range and the principle that the axial sectional areas are equal, the diameter of the punch is used as the inner diameter, and the size of the ring blank with the approximate rectangular section is determined according to the selected height ratio in equal proportion, and finally, determining the blanking volume according to the size of the ring blank with the approximately rectangular section.

3. The rolling method of the special-shaped thin-walled casing ring forging with island bosses as claimed in claim 1 or 2, wherein: the outer island boss is a cylinder, a triangular prism or a rectangular column.

4. The rolling method of the special-shaped thin-walled casing ring forging with island bosses as claimed in claim 1 or 2, wherein: before finish rolling is started, the whole circle of split molds are axially placed into the inner ring of the sleeve mold and are tightly pressed, and after finish rolling is completed, the whole circle of split molds are pressed and removed from the opposite direction.

5. The rolling method of the special-shaped thin-walled casing ring forging with island bosses as claimed in claim 1 or 2, wherein: the conical angle between the split mold and the inner ring of the cover mold is 1-3 degrees.

6. The rolling method of the special-shaped thin-walled casing ring forging with island bosses as claimed in claim 1 or 2, wherein: the number of the split molds is determined according to the number of the outer island bosses.

Technical Field

The invention belongs to the technical field of forging and ring rolling, and particularly relates to a rolling method of a special-shaped thin-wall casing ring forging with an outer island boss.

Background

In the technical field of forging and ring rolling, the forging process of rolling a ring blank with a smaller diameter and a larger wall thickness into a ring forging with a larger diameter and a thinner wall thickness is called ring rolling. The existing rolling equipment can be divided into a horizontal ring rolling mill and a vertical ring rolling mill or a radial ring rolling mill and a radial-axial ring rolling mill according to different classifications. These ring rolling mills are capable of rolling ring forged products of various cross-sectional shapes by fitting various roll shapes. However, ring forged products produced by existing ring rolling mills and rolling processes have axisymmetric revolving body characteristics, and cannot be rolled into rings with island bosses on the outer surface of the revolving body (the island bosses here indicate that the bosses have a certain height and are discontinuous and are randomly distributed on the outer surface of the revolving body ring).

For the ring part with the island boss, such as the special-shaped thin-wall casing ring forging with the island boss, a large machining allowance is generally reserved, at present, a larger rotary ring forging which envelops the island boss is rolled firstly, the island boss and other fine contours are enveloped in a plane of a cone to form a ring forging with a very large wall thickness, at the moment, the wall thickness is generally more than 40mm, and redundant materials except the boss on the outer surface are removed in a mode of numerical control milling (generally, a 3D curved surface of the outer surface needs 5-axis linkage milling because a numerical control lathe cannot process), so that raw materials are wasted (the material utilization rate is only about 5%), and only 5-axis numerical control processing can be adopted due to the non-axisymmetric rotary characteristic, the machining period and the cost are greatly increased, the integral manufacturing efficiency of the product is reduced, and particularly in the aerospace field, the high-temperature alloy titanium alloy material is used in a large amount, so that the processing difficulty is higher, and the waste raw material is more expensive. At present, even if the cover die is used for closed rolling, because the feeding and die filling processes are complicated, the temperature drop of the ring blank is too large, so that the precise characteristics of the ring piece are difficult to form, and even cannot be formed.

Disclosure of Invention

The invention aims to provide a rolling method of a special-shaped thin-wall casing ring forging with an outer island boss.

The technical scheme adopted by the invention is as follows:

a method for rolling a special-shaped thin-wall casing ring forging with an outer island boss comprises the steps that one part of a target special-shaped thin-wall casing ring forging is a ring with a nearly rectangular section, the other part of the target special-shaped thin-wall casing ring forging is a ring with a nearly conical cylinder ring and is provided with the outer island boss, blanking, upsetting and punching are firstly carried out to obtain a ring blank with the nearly rectangular section, then a single-side flaring is carried out to obtain a ring blank with a thick-wall special-shaped section, then the ring blank with the special-shaped section is obtained by rolling, then rough rolling is carried out to obtain the ring blank with the special-shaped section with an inner rotary boss, the inner rotary boss is a ring-shaped bulge which is positioned at the position, corresponding to the height position of the outer island boss, on the inner side of the nearly conical cylinder ring, then the roundness precision of the ring blank with the inner rotary boss is improved by shaping, and finally, the outer surface of the special-shaped thin-wall casing ring forging is formed by near-net shaping, and the volume of the inner rotary boss is transferred to the outer island boss to the outer surface to obtain the outer island boss;

the adopted finish rolling die comprises a driving roller, a core roller and a combined cover die which can rotate actively, wherein the driving roller or the core roller can feed linearly; the combined cover die comprises a cover die and a plurality of split dies which can be enclosed into a circle, the whole circle of split dies are detachably matched, inserted and installed on a conical surface of an inner ring of the cover die, an outer ring of the cover die is in contact with the driving roller and can be driven to rotate by the driving roller, the inner surface of the whole circle of split dies is matched with the outer surface of the special-shaped thin-wall casing ring forging, the outer surface of a working part of the core die is matched with the inner surface of the special-shaped thin-wall casing ring forging, the split dies have a structure for axially limiting a ring blank, and grooves matched with bosses of an outer island are formed in corresponding positions of the inner surface.

Further, the target size of each stage is determined by reversely pushing the special-shaped thin-wall casing part with the island boss, the size of the special-shaped thin-wall casing ring forging with the island boss is obtained according to the size of the special-shaped thin-wall casing part with the island boss and the forging allowance placed on two sides, the outer island boss of the special-shaped thin-wall casing ring forging with the island boss is removed, the volume sum of all the outer island bosses is multiplied by a plurality of times and arranged on the inner surface of the corresponding height position to obtain the size of the special-shaped cross-section ring blank with the inner rotary boss, the size of the special-shaped cross-section ring blank with the inner rotary boss is obtained by estimation according to the selected rolling ratio range and the principle that the axial cross-section is equal, the size of the thick-wall special-shaped cross-section ring blank is obtained by estimation according to the selected rolling ratio range and the principle that the axial cross-section is equal, the size of the near-rectangular cross-section ring blank is determined by taking the diameter of the punch as the inner diameter and the selected height ratio in equal proportion, and finally, determining the blanking volume according to the size of the ring blank with the approximately rectangular section.

Further, the outer island boss is a cylinder, a triangular prism or a rectangular column.

And further, before finish rolling is started, the whole circle of split dies are axially placed into the inner ring of the sleeve die and are compressed, and after finish rolling is completed, the whole circle of split dies are pressed and removed from the opposite direction.

Furthermore, the conical angle between the split mold and the inner ring of the cover mold is 1-3 degrees.

Further, the number of the split molds is determined according to the number of the outer island bosses.

The invention has the beneficial effects that:

the invention firstly obtains the special-shaped section ring blank with the inner rotary lug boss by reasonably distributing the volume through a series of preforming processes, then forms the outer surface of the special-shaped thin-wall casing ring forging by fine rolling and transfers the volume of the inner rotary lug boss to the outer surface to obtain the outer island lug boss, thereby not only ensuring the final outer diameter precision of the ring forging, but also ensuring the outer surface of the ring forging and the outer island lug boss precision, greatly improving the ring rolling precision, reducing the wall thickness to be less than 20mm, improving the material utilization rate by more than 30 percent, greatly reducing the machining allowance of the ring forging, greatly improving the production efficiency and reducing the production cost. According to the finish rolling die, the split die is matched with the conical surface of the inner ring of the sleeve die, so that the split die is convenient to mount and take out, the die can be rapidly mounted, the temperature of a ring blank is reduced, the ring blank is convenient to take out, and the split die is tightly matched with the conical surface of the sleeve die due to the axial force of the ring blank in the rolling process.

Drawings

FIG. 1 is a thin-walled profiled casing part with island bosses according to an embodiment of the invention.

FIG. 2 is a profiled thin-walled casing ring forging with island bosses according to an embodiment of the invention.

FIG. 3 is a ring blank with a profiled cross section with an internal swivel boss in an embodiment of the present invention.

Figure 4 is a profiled section ring blank in an embodiment of the invention.

FIG. 5 is a thick-walled profiled ring blank in an embodiment of the present invention.

Fig. 6 is a ring blank of approximately rectangular cross-section in an embodiment of the present invention.

FIG. 7 is a schematic view showing the operation of the finish rolling stage according to the embodiment of the present invention.

In the figure: 1-outer island boss; 2-inner rotary boss; 3-a drive roller; 4-die casting; 5-split mold; 6-special-shaped section ring blank with inner rotary boss; 7-core roll; 8-groove.

Detailed Description

The invention is further described below with reference to the figures and examples.

A rolling method of a special-shaped thin-wall casing ring forging with an outer island boss comprises the following steps:

s1, determining the target size of each stage according to the backward pushing of the special-shaped thin-wall casing part with the island boss

As shown in fig. 1, in this embodiment, one part of the special-shaped thin-walled casing part with external island bosses is a nearly rectangular cross-section ring, the other part of the special-shaped thin-walled casing part is a nearly conical cylinder ring and has an external island boss 1, the material is TC4, the outer diameter of the large end is 642mm, the outer diameter of the small end is 528mm, the axial height is 177mm, the uniform wall thickness is 2mm, the height of the nearly rectangular cross-section ring is 74mm, 12 external island bosses 1 in various shapes are uniformly distributed on the outer surface of the nearly conical cylinder ring along the circumferential direction (the shapes of the external island bosses 1 are set as required, generally common columns, in this embodiment, three types of columns, triangular prisms and rectangular columns), and the height of the external island bosses 1 is 10 mm;

firstly, obtaining the size of the special-shaped thin-wall casing ring forging with the island boss according to the size of the special-shaped thin-wall casing part with the island boss and the forging allowance (10 mm is selected) on the two sides, as shown in fig. 2;

then, removing the outer island bosses 1 of the special-shaped thin-wall casing ring forging with the outer island bosses, and arranging the volume of all the outer island bosses 1 which is multiple times (4-8 times, 6 times) on the inner surface of the corresponding height position to obtain the size of the special-shaped section ring blank 6 with the inner rotary boss, as shown in fig. 3;

then, estimating according to the selected rolling ratio range (1.3-1.7, 1.5 is taken) and the principle that the axial sectional areas are equal to obtain the special-shaped section ring blank, wherein as shown in FIG. 4, the outer diameter of the small end is 400mm, the inner diameter of the small end is 320mm, the outer diameter of the large end is 544mm, and the inner diameter of the large end is 452 mm;

then estimating the size of the thick-wall deformed section ring blank according to the selected rolling ratio range and the principle that the axial sectional areas are equal, and obtaining the size of the thick-wall deformed section ring blank as shown in figure 5;

and then, the diameter of the punch is used as the inner diameter (120 mm is selected), and the size of the ring blank with the approximate rectangular section is determined according to the equal proportion of the selected height ratio (the height of the ring blank with the approximate rectangular section is 1.1-1.2 times of the height of the ring blank with the thick-wall special-shaped section), as shown in fig. 6, the inner diameter is 120mm, the small end outer diameter is 268mm, and the large end outer diameter is 290 mm.

And finally, determining the blanking volume according to the size of the ring blank with the approximately rectangular section.

S2, reasonably distributing the volume through a series of pre-forming processes to obtain the special-shaped section ring blank 6 with the inner rotary boss

Firstly, blanking, upsetting and punching to obtain a ring blank with a nearly rectangular section, then heating the ring blank with the nearly rectangular section to a forming temperature, flaring a single side in a die to obtain a ring blank with a thick-wall irregular section, then rolling the ring blank with the thick-wall irregular section on a ring rolling mill to obtain the ring blank with the irregular section, replacing a driving roller and a core roller, firstly, rough rolling to obtain the ring blank 6 with the irregular section with an inner rotary boss, wherein the inner rotary boss 2 is a ring-shaped protrusion which is positioned at the position, corresponding to the height position of the outer island boss 1, of the inner side of the nearly conical cylinder ring, and then shaping to improve the roundness precision of the ring blank 6 with the irregular section and the inner rotary boss.

S3, finish rolling to obtain the special-shaped thin-wall casing ring forging with the island boss

As shown in fig. 7, the finish rolling die comprises a driving roller 3, a core roller 7 and a combined cover die which can actively rotate, wherein the driving roller 3 or the core roller 7 can be linearly fed; the combined cover die comprises a cover die 4 and a plurality of split dies 5 which can be enclosed into a circle (the number of the split dies 5 is determined according to the number of the outer island bosses 1, 12 split dies 5 are adopted in the embodiment), the whole circle of split dies 5 are detachably matched, inserted and installed on a conical surface of an inner ring of the cover die 4 (the conical surface taper angle between the split dies 5 and the inner ring of the cover die 4 is 1-3 degrees), the outer ring of the cover die 4 is in contact with the driving roller 3 and can be driven to rotate by the driving roller 3, the inner surface of the whole circle of split dies 5 is matched with the outer surface of the special-shaped thin-wall casing ring forging, the outer surface of the working part of the core die 7 is matched with the inner surface of the special-shaped thin-wall casing ring forging, the split dies 5 have a structure for axially limiting the ring blank 6, and grooves 8 matched with the outer island bosses 1 are arranged at corresponding positions of the inner surface;

before finish rolling begins, firstly, a special-shaped section ring blank 6 with an internal rotary boss and a whole circle of split dies 5 are axially placed into an inner ring of a sleeve die 4 and compressed, during finish rolling, the outer surface of the special-shaped thin-wall casing ring forging is formed in a near-net mode, the volume of an internal rotary boss 2 is transferred to the outer surface to obtain an external island boss 1, redundant materials are left on the inner surface to facilitate turning removal, during the hot forming process, the hot forming temperature needs to be reheated to the hot forming temperature in due time according to the temperature reduction condition of a workpiece, after finish rolling is completed, the whole circle of split dies 5 are pressed off in the opposite direction on a press machine, the split dies 5 are separated, and the special-shaped thin-wall casing ring forging with the external island boss is taken out.

According to the invention, the volume is reasonably distributed through a series of preforming processes to obtain the special-shaped section ring blank 6 with the inner rotary boss, then the outer surface of the special-shaped thin-wall casing ring forging is precisely rolled and formed, and the volume of the inner rotary boss 2 is transferred to the outer surface to obtain the outer island boss 1, so that the final outer diameter precision of the ring forging can be ensured, the precision of the outer surface of the ring forging and the precision of the outer island boss 1 can also be ensured, the rolling precision of the ring forging is greatly improved, the wall thickness is reduced to be below 20mm, the material utilization rate is improved by more than 30%, the machining allowance of the ring forging is greatly reduced, the production efficiency is greatly improved, and the production cost is reduced. According to the finish rolling die, the split die 5 is matched with the conical surface of the inner ring of the sleeve die 4, so that the split die 5 is convenient to mount and take out, the die can be rapidly mounted, the temperature of the ring blank 6 is reduced, the ring blank can be conveniently taken out by a tool, and the split die 5 is tightly matched with the conical surface of the sleeve die 4 under the axial force of the ring blank 6 in the rolling process.

It will be understood that modifications and variations can be made by persons skilled in the art in light of the above teachings and all such modifications and variations are intended to be included within the scope of the invention as defined in the appended claims.