阅读说明：本技术 一种nu2300系列轴承套锻工艺 (NU2300 series bearing sleeve forging process ) 是由 段少杰 马志杰 杨斯一 张哲通 刘长建 于卫国 兰江涛 于 2020-10-21 设计创作，主要内容包括：一种NU2300系列轴承套锻工艺,涉及轴承锻造技术,包括对轴承外圈锻料、轴承内圈锻料的加工；轴承外圈锻件的棒料通过电炉加热、切料、镦饼、分套、平高、外圈扩孔、外圈整径工序完成；轴承内圈锻料通过对分套料芯镦饼、反挤成形、穿孔平高、内圈扩孔、内圈整径工序完成；反挤成形工序包括反挤冲头和反挤凹模,将分套料芯镦饼的料坯放入反挤凹模内,通过反挤冲头的挤压及下平面的压力下,形成反挤料坯,反挤冲头的下平面压住反挤料坯的上平面,反挤料坯的上面凸出反挤凹模的上端面4-6mm；反挤料坯的高度B1是平高料坯高度B2的1.08-1.12倍；本发明有效降低了废品率,提升了材料利用率和车加工效率。(A NU2300 series bearing sleeve forging process relates to the bearing forging technology, and comprises processing bearing outer ring forging materials and bearing inner ring forging materials; the method comprises the following steps that a bar of the bearing outer ring forge piece is heated by an electric furnace, cut, upset cake, split sleeve, flat height, outer ring reaming and outer ring diameter sizing; forging the bearing inner ring by the procedures of upsetting cakes by split sleeve core, reverse extrusion forming, punching and leveling, reaming the inner ring and sizing the inner ring; the backward extrusion forming process comprises a backward extrusion punch and a backward extrusion female die, wherein a material blank of the sleeve material core upsetting cake is placed into the backward extrusion female die, a backward extrusion material blank is formed under the extrusion of the backward extrusion punch and the pressure of a lower plane, the lower plane of the backward extrusion punch presses the upper plane of the backward extrusion material blank, and the upper surface of the backward extrusion material blank protrudes out of the upper end surface of the backward extrusion female die by 4-6 mm; the height of the backward extrusion preform B1 was 1.08-1.12 times the height of the flat height preform B2; the invention effectively reduces the rejection rate and improves the material utilization rate and the turning efficiency.)

1. The utility model provides a NU2300 series bearing shell forging technology, includes the processing of forging material, bearing inner race forging material to bearing inner race, characterized by: the method comprises the following steps that a bar of the bearing outer ring forge piece is heated by an electric furnace, cut, upset cake, split sleeve, flat height, outer ring reaming and outer ring diameter sizing; forging the bearing inner ring by the procedures of upsetting cakes by split sleeve core, reverse extrusion forming, punching and leveling, reaming the inner ring and sizing the inner ring;

wherein, the height A1 of the cake blank of the bearing outer ring is 1.2 to 1.25 times of the height A2 of the flat blank;

the backward extrusion forming process adopts a semi-closed backward extrusion device which comprises a backward extrusion punch and a backward extrusion female die, wherein a material blank of the sleeve material core upsetting cake is placed in the backward extrusion female die, a backward extrusion material blank is formed under the extrusion of the backward extrusion punch and the pressure of a lower plane, the lower plane of the backward extrusion punch presses the upper plane of the backward extrusion material blank, and the upper surface of the backward extrusion material blank protrudes out of the upper end surface of the backward extrusion female die by 4-6 mm; the height of the backward extrusion preform B1 was 1.08-1.12 times the height of the flat height preform B2;

the punching flat height adopts a semi-closed device, which comprises a punching punch, a supporting female die, a flattening sleeve and a punching female die, wherein the inner surface of the supporting female die is arranged into an inverted cone, the punching female die is fixed in a bottom surface step of the supporting female die, a boss is processed at the center of the upper surface of the punching female die, a punching flat height blank is placed in the supporting female die, the upper surface of the punching flat height blank protrudes out of the upper end surface of the supporting female die by 5-8mm, the lower surface of the punching flat height blank is attached to the upper surface of the punching female die, a discharge plate is arranged at the root of the upper end of the punching punch, the flattening sleeve in a shape like a Chinese character 'ji' is arranged between the discharge plate and the punching punch, inclined surfaces which are inwards and upwards inclined are processed at two sides of the lower surface of the flattening sleeve, the inclination angle alpha 3 is 10-15 degrees, the inclined surfaces are in contact with the upper end surface, The center of the punch die.

2. The NU2300 series bearing shell forging process of claim 1, wherein: the temperature of the electric furnace for heating the bar stock is 1000-.

3. The NU2300 series bearing shell forging process of claim 1, wherein: the size of the boss is 5mm wide, 2mm high.

Technical Field

The invention relates to a bearing forging technology, in particular to a NU2300 series bearing sleeve forging process.

Background

As is known, the ratio of the outer diameter to the height of a NU2300 series bearing reaches about 2.5, the ratio of the outer diameter to the height of a conventional bearing product is about 4.0, the smaller the ratio of the outer diameter to the height of the bearing product in forging, the larger the machining difficulty coefficient, the thicker the wall, the higher the height and the smaller the rolling expansion ratio, and the defects of blanks generated in the forging process are not completely eliminated after rolling expansion, such as the defects of larger outer chamfer of an outer ring, larger inner chamfer of an inner ring, concave end face of the inner ring and the like, the short reaming time can cause the outer chamfer of a forging to be not full, the long reaming time can cause the inner diameter taper and the inner diameter of the forging to generate axial burrs, so that the forging defects bring potential quality hazards to the product and the higher rejection rate. Because the existing process method and die can not meet the process requirements of products, in order to eliminate the defects of forgings, the amount of forgings is increased at present, and the defects of the forgings are eliminated through turning, so that the consumption of forging materials is increased, the turning amount of the turning is increased, the turning efficiency is reduced, and finally the manufacturing cost of the bearing is increased.

Disclosure of Invention

In order to overcome the defects in the background art, the invention discloses a NU2300 series bearing sleeve forging process.

In order to realize the purpose, the invention adopts the following technical scheme:

a NU2300 series bearing sleeve forging process comprises processing bearing outer ring forging materials and bearing inner ring forging materials; the method comprises the following steps that a bar of the bearing outer ring forge piece is heated by an electric furnace, cut, upset cake, split sleeve, flat height, outer ring reaming and outer ring diameter sizing; forging the bearing inner ring by the procedures of upsetting cakes by split sleeve core, reverse extrusion forming, punching and leveling, reaming the inner ring and sizing the inner ring;

wherein, the height A1 of the cake blank of the bearing outer ring is 1.2 to 1.25 times of the height A2 of the flat blank;

the backward extrusion forming process adopts a semi-closed backward extrusion device which comprises a backward extrusion punch and a backward extrusion female die, wherein a material blank of the sleeve material core upsetting cake is placed in the backward extrusion female die, a backward extrusion material blank is formed under the extrusion of the backward extrusion punch and the pressure of a lower plane, the lower plane of the backward extrusion punch presses the upper plane of the backward extrusion material blank, and the upper surface of the backward extrusion material blank protrudes out of the upper end surface of the backward extrusion female die by 4-6 mm; the height of the backward extrusion preform B1 was 1.08-1.12 times the height of the flat height preform B2;

the punching flat height adopts a semi-closed device, which comprises a punching punch, a supporting female die, a flattening sleeve and a punching female die, wherein the inner surface of the supporting female die is arranged into an inverted cone, the punching female die is fixed in a bottom surface step of the supporting female die, a boss is processed at the center of the upper surface of the punching female die, a punching flat height blank is placed in the supporting female die, the upper surface of the punching flat height blank protrudes out of the upper end surface of the supporting female die by 5-8mm, the lower surface of the punching flat height blank is attached to the upper surface of the punching female die, a discharge plate is arranged at the root of the upper end of the punching punch, the flattening sleeve in a shape like a Chinese character 'ji' is arranged between the discharge plate and the punching punch, inclined surfaces which are inwards and upwards inclined are processed at two sides of the lower surface of the flattening sleeve, the inclination angle alpha 3 is 10-15 degrees, the inclined surfaces are in contact with the upper end surface, The center of the punch die.

In the NU2300 series bearing sleeve forging process, the temperature of the electric furnace for heating the bar stock is 1000-1175 ℃.

According to the NU2300 series bearing sleeve forging process, the size of the boss is 5mm in width and 2mm in height.

Due to the adoption of the technical scheme, the invention has the following beneficial effects:

1. according to the NU2300 series bearing sleeve forging process, in order to avoid the end face concave center generated by the outer ring forging in the reaming process, the angle alpha 1 generated by the blank in the sleeve separating process needs to be eliminated, so that the height A1 of the upsetting cake blank is set to be 1.2-1.25 times of the height A2 of the flat blank; in order to avoid overlarge inner chamfer generated by the inner ring forge piece in the hole expanding and height leveling process, the angle alpha 2 generated by the blank in the backward extrusion forming process needs to be eliminated, and the height B1 of the backward extrusion blank 4 is set to be 1.08-1.12 times of the height B2 of the horizontal height blank; the backward extrusion blank 4 protrudes 4-6mm out of the backward extrusion concave die, so that the backward extrusion blank 4 is formed in the backward extrusion concave die 3, the outer diameter shape of the blank is effectively improved, the lower plane 2 of the backward extrusion punch 1 presses the upper plane of the backward extrusion blank 4, the parallelism difference of the blank is eliminated, and powerful conditions are created for the punching height leveling process.

2. According to the NU2300 series bearing sleeve forging process, the punched flat-high blank protrudes out of the female die by 5-8mm, the outer diameter bulging of the punched flat-high blank is reduced, and the defect of outer chamfering of a hole expansion is eliminated; processing an angle alpha 3 on the bottom surface of the flattening sleeve, wherein the angle alpha 3 is 10-15 degrees, and the end surface concave center generated by hole expansion can be eliminated; and a boss is processed on the upper plane of the perforation female die, so that the inner diameter axial burrs generated by reaming can be eliminated. The invention effectively reduces the rejection rate and improves the material utilization rate and the turning efficiency.

Drawings

FIG. 1 is a process flow diagram of the present invention;

FIG. 2 is a schematic structural view of a semi-enclosed reverse extrusion apparatus of the present invention;

FIG. 3 is a schematic view of a semi-enclosed structure for a piercing station according to the present invention;

in the figure: 1. a backward extrusion punch; 2. a lower plane; 3. reversely extruding the female die; 4. reversely extruding the blank; 5. flattening the sleeve; 6. punching a flat blank; 7. supporting the female die; 8. punching a female die; 9. a boss; 10. a piercing punch; 11. and (4) a stripper plate.

Detailed Description

The present invention will be explained in detail by the following examples, which are disclosed for the purpose of protecting all technical improvements within the scope of the present invention.

With the combination of the forging process of the bearing sleeve of NU2300 series shown in the attached drawings, the forging process comprises the steps of processing forged materials of the outer ring and the inner ring of the bearing; the method comprises the following steps that a bar of the bearing outer ring forge piece is heated by an electric furnace, cut, upset cake, split sleeve, flat height, outer ring reaming and outer ring diameter sizing; forging the bearing inner ring by the procedures of upsetting cakes by split sleeve core, reverse extrusion forming, punching and leveling, reaming the inner ring and sizing the inner ring;

wherein, the height A1 of the cake blank of the bearing outer ring is 1.2 to 1.25 times of the height A2 of the flat blank;

the backward extrusion forming process adopts a semi-closed backward extrusion device which comprises a backward extrusion punch 1 and a backward extrusion female die 3, wherein a blank of the sleeve material core upsetting cake is placed into the backward extrusion female die 3, a backward extrusion material blank 4 is formed under the extrusion of the backward extrusion punch 1 and the pressure of a lower plane 2, the lower plane 2 of the backward extrusion punch 1 presses an upper plane of the backward extrusion material blank 4, and the upper surface of the backward extrusion material blank 4 protrudes out of the upper end surface of the backward extrusion female die 3 by 4-6 mm; the height B1 of the back extrusion blank 4 is 1.08-1.12 times of the height B2 of the flat height blank;

the punching height leveling device adopts a semi-closed device, and comprises a punching punch 10, a supporting female die 7, a leveling sleeve 5 and a punching female die 8, wherein the inner surface of the supporting female die 7 is arranged into an inverted cone shape, the punching female die 8 is fixed in a bottom surface step of the supporting female die 7, a boss 9 is processed at the center of the upper surface of the punching female die 8, a punching height leveling blank 6 is placed in the supporting female die 7, the upper surface of the punching height leveling blank 6 protrudes out of the upper end surface of the supporting female die 7 by 5-8mm, the lower surface of the punching height leveling blank 6 is attached to the upper surface of the punching female die 8, a discharge plate is arranged at the root part of the upper end of the punching punch 10, a 'n' -shaped leveling sleeve 5 is arranged between the discharge plate and the punching punch 10, inward and upward inclined planes are processed on both lower sides of the leveling sleeve 5, the inclination angle alpha 3 is 10-15 degrees, and the inclined planes are, the lower end of the perforating punch 10 sequentially passes through the center hole of the perforating flat blank 6 and the center of the perforating concave die 8.

In the NU2300 series bearing sleeve forging process, the temperature of the electric furnace for heating the bar stock is 1000-1175 ℃.

According to the NU2300 series bearing sleeve forging process, the boss 9 is 5mm wide and 2mm high. The NU2300 series bearing sleeve forging process is implemented, a bar material of a bearing outer ring forging material is heated to 1000-inch-adding 1175 ℃ in a heating furnace, the heated bar material is cut and then placed on a press machine for upsetting cakes and sleeve separation, the heated bar material is separated into a bearing outer ring material blank and a sleeve separation material core, the outer ring material blank is processed into a bearing outer ring forging piece, and the sleeve separation material core is processed into a bearing inner ring forging piece;

in order to avoid the end face concave center generated by the outer ring forging in the hole expanding process, the angle alpha 1 generated by the blank in the sleeve separating process needs to be eliminated, so that the height A1 of the upsetting cake blank is set to be 1.2-1.25 times of the height A2 of the flat blank; then, the procedures of leveling, outer ring reaming and outer ring diameter sizing are carried out;

the sleeve material core is subjected to cake upsetting and backward extrusion forming, in order to avoid overlarge inner chamfer generated by a bearing inner ring forge piece in a hole expanding and height leveling process, the angle alpha 2 generated by a material blank in the backward extrusion forming process needs to be eliminated, and the height B1 of a backward extrusion material blank 4 is set to be 1.08-1.12 times of the height B2 of a perforation height leveling material blank; in the backward extrusion forming process, a blank of the sleeve material core heading cake is placed into a backward extrusion female die 3, a backward extrusion blank 4 is formed under the extrusion of a backward extrusion punch 1 and the pressure of a lower plane 2, the lower plane 2 of the backward extrusion punch 1 presses the upper plane of the backward extrusion blank 4, the upper surface of the backward extrusion blank 4 protrudes 4-6mm out of the upper end surface of the backward extrusion female die 3, the blank is formed in the backward extrusion female die, the outer diameter shape of the blank is effectively improved, the lower plane of the backward extrusion punch presses the upper plane of the blank, the parallel difference of the blank is eliminated, and powerful conditions are created for the perforation leveling process; in the perforation leveling procedure, a perforation leveling blank 6 is placed in a supporting concave die 7, the upper surface of the perforation leveling blank 6 protrudes out of the upper end surface of the supporting concave die 7 by 5-8mm, the outer diameter bulging of the perforation leveling blank is reduced, and the defect of reaming outer chamfer is eliminated; the lower surface of the perforation flat height blank 6 is attached to the upper surface of the perforation concave die 8 and the lug boss 9, and the lug boss is processed on the upper plane of the perforation concave die, so that inner diameter axial burrs generated by reaming can be eliminated; the lower end of a perforating punch 10 sequentially penetrates through a center hole of a perforating flat blank 6 and the center of a perforating female die 8, inward and upward inclined planes are processed on two sides of the lower surface of a flattening sleeve 5, the inclination angle alpha 3 is 10-15 degrees, and end face concave centers generated by hole expansion can be eliminated; and then the processing of the bearing inner ring forge piece is finished through inner ring chambering and inner ring diameter-finishing.

The present invention is not described in detail in the prior art.

The embodiments selected for the purpose of disclosing the invention, are presently considered to be suitable, it being understood, however, that the invention is intended to cover all variations and modifications of the embodiments which fall within the spirit and scope of the invention.