CN116078966A

CN116078966A - Multidirectional die forging forming method for bearing saddle forging piece

Info

Publication number: CN116078966A
Application number: CN202210838381.5A
Authority: CN
Inventors: 徐文翠; 代锦阳; 纪宏超; 胡艳军
Original assignee: Zhongye Heavy Industry Tangshan Co ltd; North China University of Science and Technology
Current assignee: Zhongye Heavy Industry Tangshan Co ltd; North China University of Science and Technology
Priority date: 2021-11-04
Filing date: 2022-07-18
Publication date: 2023-05-09
Also published as: CN113996740A

Abstract

The invention discloses a multidirectional die forging forming method of a bearing saddle forging piece, and relates to the technical field of manufacturing of bearing saddles. The multi-directional die forging forming technology of one-fire one procedure is adopted to produce the bearing saddle forging piece with the appearance and the size close to the parts, the dimensional precision of the parts such as the oil groove, the side surface and the bottom surface of the bearing saddle meets the use requirement, and the subsequent machining is not needed; in addition, the mechanical property and the wear resistance of the product are obviously improved, the service life of equipment is prolonged, the maintenance cost of the equipment is saved, the forging process is few, the productivity is high, and the energy consumption is low.

Description

Multidirectional die forging forming method for bearing saddle forging piece

Technical Field

The invention relates to the technical field of manufacturing of bearing saddles, in particular to a multidirectional die forging forming method of a bearing saddle forging piece.

Background

The bearing saddle is applied to freight train carriages and is an important accessory of a freight train running part. The bearing saddle is arranged between the truck side frame and the rolling bearing of the freight train, and is used for bearing and transmitting abrasion generated by contact with the truck side frame and the bearing in the running process of the freight train, and if the bearing saddle is excessively worn, the normal running of the train is seriously affected. At present, the domestic bearing saddle mainly adopts a casting forming process, the mechanical property of the product is low, the product is easy to wear in use, and once the product is difficult to repair in the later period of wear, the whole bearing saddle is often required to be replaced, so that raw materials are wasted and the equipment maintenance cost is high.

Disclosure of Invention

In order to solve the technical problems, the invention provides a multidirectional die forging forming method for a bearing saddle forging, wherein the bearing saddle forging is formed in a multidirectional die forging mode, so that the mechanical property of a product can be improved, the wear resistance and the service life of the bearing saddle forging are improved, and the equipment maintenance cost is saved.

In order to achieve the technical purpose, the invention adopts the following scheme: the multidirectional die forging forming method of the bearing saddle forging comprises the following steps:

s1, blanking: the blank adopts a cylindrical bar stock;

s2, die installation: the lower die assembly and the upper die assembly are arranged on the forging platform, so that the positioning accuracy and the centering accuracy of the upper die assembly and the lower die assembly during die installation are ensured, and the centering accuracy is less than or equal to +/-0.3 mm;

s3, heating: heating the blank to 1220+/-20 ℃ of initial forging temperature, and keeping the temperature for more than or equal to 0.5h; preheating a die to 200 ℃ by adopting an electric heating belt;

s4, forging:

s4-1, discharging the blank and preparing for forging after the blank and the die reach the set temperature and meet the heat preservation time requirement;

s4-2, placing blanks: the upper die assembly is 400mm away from the upper surface of the lower die assembly, the lower ejector block moves upwards, the round bar material is placed in a positioning arc groove of the lower ejector block, then the lower ejector block returns to the initial position, and the round bar material is positioned to the bottom surface of the lower die cavity;

s4-3, horizontal male die pre-positioning: the horizontal male die is predefined in advance to the cavity of the lower female die;

s4-4, descending the upper die assembly: the upper die assembly adopts a displacement control mode, meets the height and size requirements, and stops descending when the displacement reaches a set value;

s4-5, opposite extrusion of a horizontal male die: the horizontal male die performs opposite extrusion in a pressure control mode, and when the extrusion pressure reaches a set value, the horizontal male die stops extrusion to finish forging;

s4-6, transferring forging: the upper die assembly moves upwards and is 400mm away from the upper surface of the lower die assembly, and the bearing saddle forge piece is ejected out by the ejector rod and the lower ejector block.

Compared with the prior art, the invention has the beneficial effects that: the multi-directional die forging forming technology of one-fire one procedure is adopted to produce the bearing saddle forging piece with the appearance and the size close to the parts, the dimensional precision of the parts such as the oil groove, the side surface and the bottom surface of the bearing saddle meets the use requirement, and the subsequent machining is not needed; in addition, the mechanical property and the wear resistance of the product are obviously improved, the service life of equipment is prolonged, the maintenance cost of the equipment is saved, the forging process is few, the productivity is high, and the energy consumption is low.

The preferable scheme of the invention is as follows:

the diameter of the round bar material is 140mm, and the length of the round bar material is 240-280 mm.

S3, heating the blank and keeping the blank warm for more than or equal to 1.2 hours; the preheating time of the die is more than or equal to 4 hours.

And S4-2, lifting the lower top block upwards by 180-220 mm along the Z axis.

And the displacement setting value of the male die on the S4-4 along the Z axis is 400mm.

S4-5 the opposite extrusion pressure of the horizontal male die along the X axis is set to be 300bar.

And the ejection height of the S4-6 is 200mm.

Drawings

Fig. 1 is a schematic structural view of a bearing saddle according to an embodiment of the present invention;

fig. 2 is a cross-sectional view of a multi-directional swage forming die for an adapter provided in an embodiment of the present invention;

FIG. 3 is a side view of the A-A plane of FIG. 2;

FIG. 4 is an assembled view of a portion of an upper punch provided in an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a lower top block according to an embodiment of the present invention;

FIG. 6 is a cross-sectional view of a lower die according to an embodiment of the present invention;

fig. 7 is a diagram of an initial placement position of round bars according to an embodiment of the present invention;

FIG. 8 is a cross-sectional view of a lower die assembly after resetting a lower top block and predefining a horizontal punch according to an embodiment of the present invention;

FIG. 9 is a diagram showing the completion of forging according to an embodiment of the present invention;

FIG. 10 is a drawing showing the opening of the bearing saddle according to the embodiment of the present invention;

marked in the figure as: 1. a push rod; 2. a lower die backing plate; 3. a lower female die; 4. a lower top block; 5. a horizontal male die; 6. a semi-cylindrical upper male die; 7. a top plate of the upper male die; 8. an upper male die connecting plate; 9. an upper male die backing plate; 10. an upper punch side plate; 11. positioning an arc-shaped groove; 12. round bar stock; 13. and carrying a saddle forging.

Detailed Description

The present invention will be described in detail with reference to the following embodiments for a full understanding of the objects, features and effects of the present invention, but the present invention is not limited thereto.

The bearing saddle forging consists of a guide frame flange, a saddle surface annular belt, an oil groove, a positioning block, a top surface and a thrust block shoulder, as shown in fig. 1.

The multi-directional die forging forming die for the bearing saddle consists of an upper die assembly, a lower die assembly, a horizontal male die 5 and the like, wherein the upper die assembly, the lower die assembly and the horizontal male die 5 are clamped to obtain a die cavity structure in the shape of the bearing saddle, and the die cavity structure is shown in fig. 2 and 3.

The upper die assembly consists of an upper punch backing plate 9, an upper punch connecting plate 8, an upper punch side plate 10, an upper punch top plate 7 and a semi-cylindrical upper punch 6, wherein the lower surface of the upper punch backing plate 9 is attached to the upper surface of the upper punch connecting plate 8, a cross clamping groove is formed in the middle of the lower surface of the upper punch connecting plate 8, and the upper punch top plate 7 and the upper punch side plate 10 are clamped in the cross clamping groove. The length of the X, Y shaft of the upper punch top plate 7 is smaller than the corresponding dimension of the clamping groove, and the single-side clearance is 0.2mm. The two sides of the end face of the upper punch top plate 7 parallel to the Y axis are respectively attached with an upper punch side plate 10 to form a cross structure, and the outer side wall of the upper punch side plate 10 is attached with the groove wall of the cross clamping groove of the upper punch connecting plate 8, as shown in fig. 4.

The semi-cylindrical upper punch 6 and the upper punch top plate 7, and the semi-cylindrical upper punch 6 and the upper punch side plate 10 are connected by adopting square keys and screws, and the concrete structure is as follows: the semi-cylindrical upper male die 6 is horizontally placed, the arc face is downward, the horizontal plane is upward, a first positioning groove is formed in the center of the horizontal plane, a positioning block is arranged in the center of the lower surface of the upper male die top plate 7, and the positioning block is embedded in the positioning groove. The arc surface of the semi-cylindrical upper male die 6 is provided with a structure matched with a saddle surface girdle and an oil groove of the bearing saddle. Second positioning grooves are respectively formed in the two semicircular end faces of the semi-cylindrical upper male die 6, second positioning blocks are arranged on the lower portion of the side wall of the upper male die side plate 10, and the second positioning blocks are embedded in the second positioning grooves.

The outer edge of the lower surface of the upper punch top plate 7 is attached to the upper surface of the horizontal punch 5, and the horizontal punch 5 is inserted into the lower die assembly.

The lower die assembly comprises a lower female die 3, a lower top block 4 and a lower die backing plate 2, a die cavity with the same main structure as the middle part of the bearing saddle is formed in the upper part of the axial center of the lower female die 3, rectangular notches are formed in the side walls of the die cavity of the lower female die 3 symmetrical about the center line parallel to the Y axis respectively, the notches are used for placing a horizontal male die 5, the horizontal male die 5 is two cuboid blocks, and one cuboid block is placed in each notch.

The lower die 3 is provided with a cylindrical cavity at the lower part of the axial center, the die cavity is communicated with the cylindrical cavity to form a step-shaped structure, and the cylindrical cavity is internally provided with a lower jacking block 4 in sliding connection. A positioning arc groove 11 is formed in the center of the upper surface of the lower ejector block 4, the positioning arc groove 11 extends to the upper surface of the step of the die cavity, and the positioning arc groove 11 is used for limiting the round bar 12, as shown in fig. 5 and 6. The lower surface of the lower female die 3 is attached to the upper surface of the lower die cushion plate 2, the lower die cushion plate 2 is placed on the working surface, a through hole is formed in the center of the lower die cushion plate 2, a push rod 1 in sliding connection is arranged in the through hole, and the upper end of the push rod 1 is connected with the lower end of the lower push block 4 through a screw rod.

When the die is assembled, the symmetrical center lines of all the parts in the Z-axis direction are collinear. The upper die assembly is connected with a movable cross beam of the hydraulic machine, vertical forming force is provided by a vertical cylinder of the hydraulic machine, the lower die assembly is connected with a workbench of the hydraulic machine, the horizontal male die 5 is connected with a horizontal cylinder of the hydraulic machine, and horizontal forming force is provided by the horizontal cylinder.

The invention provides a multidirectional die forging forming method of a bearing saddle forging piece, which comprises the following steps:

s1, blanking: the blank adopts a round bar 12 with the diameter of phi 140mm and the length is about 260mm, and the diameter blank can meet the requirement that the length of the blank is not greatly different from the length and the size of the bearing saddle forge piece 13, so that the forming quality of the forge piece is ensured.

S2, die installation: according to the invention, the mould is installed according to the mould structure, and the positioning precision and the centering precision of the upper mould component and the lower mould component during the installation of the mould are ensured, wherein the centering precision is not more than +/-0.3 mm.

S3, heating: heating the blank to 1220+/-20 ℃ of initial forging temperature, keeping the temperature for not less than 0.5h, and keeping the total heating (heating and keeping the temperature) time of the blank for not less than 1.2h, thereby ensuring uniform heating; the die is preheated to 200+/-20 ℃ by adopting an electric heating belt, and the total preheating time is not less than 4 hours.

S4, forging:

s4-1, discharging the blank and the die to prepare forging after the blank meets the heat preservation time requirement and reaching the set temperature.

S4-2, placing blanks: the upper die assembly is 400mm away from the upper surface of the lower die assembly (namely, the distance between the upper surface of the lower female die 3 and the lower surface of the semi-cylindrical upper male die 6), the lower ejector block 4 ascends by about 200mm along the Z axis, the round bar stock 12 is placed in the positioning arc groove 11 of the lower ejector block 4, as shown in fig. 7, then the lower ejector block 4 is retracted to the initial position, and the round bar stock 12 is positioned to the bottom surface of the die cavity of the lower female die 3.

S4-3, presetting the horizontal male die 5: the horizontal male die 5 is predefined in advance to 8-12 mm in the cavity of the lower female die 3, as shown in fig. 8, so that the flow condition of metal is improved, and the generation of longitudinal flash is prevented.

S4-4, integrally descending an upper die: the upper die assembly adopts a displacement control mode to meet the height and size requirements, and the whole upper die assembly is forged until the displacement reaches the set value of 400mm, and then the descending is stopped.

S4-5, opposite extrusion of a horizontal male die 5: the horizontal male die 5 adopts a pressure control mode to ensure the filling quality of the forging; when the horizontal punch 5 is extruded along the X-axis direction until the pressure reaches the set value of 300bar, the horizontal punch 5 stops extrusion, and the forging process is completed, as shown in FIG. 9.

S4-6, transferring forging: the whole upper die assembly moves upwards along the Z axis and is 400mm away from the upper surface of the whole lower die (namely, the distance from the upper surface of the lower female die 3 to the lower surface of the semi-cylindrical upper male die 6), then the lower ejection mechanism consisting of the ejector rod 1 and the lower ejector block 4 ejects the bearing saddle forging 13, the ejection height is 200mm, and the bearing saddle forging is transferred to a conveying chain by a manipulator as shown in fig. 10.

S5, the next cycle.

The multi-directional die forging forming process and the forming die with one fire and one working procedure can produce the bearing saddle forging 13 with the appearance and the size close to the parts, the dimensional precision of the parts such as the oil groove, the side surface and the bottom surface meets the use requirement, the subsequent machining is not needed, in addition, the mechanical property and the wear resistance of the product are obviously improved, the service life of equipment is prolonged, the maintenance cost of the equipment is saved, the forging working procedure is less, the production rate is high, and the energy consumption is less.

After heat treatment of the bearing saddle forging, mechanical property detection is carried out, mechanical and impact samples are prepared from the length direction of the top surface, the width direction and the length direction of the side surface of the forging respectively, and after the samples are processed to the standard size, tensile and impact property detection is carried out, wherein the mechanical property detection results are shown in Table 1.

Table 1 mechanical properties of bearing saddle forgings

As can be seen from Table 1, the measured average value of the mechanical properties of the forging in all directions is higher than the minimum standard value, and the measured data of the mechanical properties in the three directions are not much different. The bearing saddle forging produced by adopting the multidirectional die forging forming process is stressed in three directions, so that the structure is more compact, and the product performance is more uniform and excellent.

Finally, it should be noted that: the above list is only a preferred embodiment of the present invention, and it is understood that those skilled in the art can make modifications and variations thereto, and it is intended that the present invention be construed as the scope of the appended claims and their equivalents.

Claims

1. The multidirectional die forging forming method for the bearing saddle forging is characterized by comprising the following steps of:

s1, blanking: round bar stock is adopted as the blank;

s3, heating: heating the blank to the initial forging temperature 1220+/-20 ℃ and keeping the temperature for more than or equal to 0.5h; preheating a die to 200 ℃ by adopting an electric heating belt;

s4, forging:

2. The multi-directional die forging forming method of the bearing saddle forging according to claim 1, wherein the diameter of the round bar is 140mm, and the length of the round bar is 240-280 mm.

3. The multi-directional die forging forming method of the bearing saddle forging piece according to claim 1, wherein the total time of blank heating and blank heat preservation in the step S3 is more than or equal to 1.2h; the preheating time of the die is more than or equal to 4 hours.

4. The multi-directional die forging forming method of the bearing saddle forging piece according to claim 1, wherein the S4-2 lower top block is located 180-220 mm upwards.

5. The method of multi-directional swaging a saddle-forgeable piece according to claim 1, wherein the set value of the punch displacement on S4-4 is 400mm.

6. The multi-directional forging forming method of a saddle-shaped forgings according to claim 1, wherein the set value of the S4-5 horizontal punch counter-extrusion pressure is 300bar.

7. The method of multi-directional swaging of a saddle-forgeable piece according to claim 1, wherein the S4-6 ejection height is 200mm.