High-strength bearing ring production process

Abstract

The invention discloses a high-strength bearing ring production process which comprises the following specific production process steps: step 1, selecting a bearing ring production bar material, inspecting the bar material by an inspector, carrying out pilot run on production equipment, and carrying out technical disclosure to a worker; secondly, the bar is subjected to cold drawing through cold drawing equipment, the outer diameter of the bar is made to be the size needed by the bearing ring, then the bar obtained after cold drawing is subjected to axial drilling through a numerical control lathe, the hole diameter is the inner diameter of the bearing ring, then the bar is subjected to radial cutting according to the needed size, and a blank is obtained; and thirdly, the blank obtained in the second step is subjected to electric induction heating treatment before forging, so that the plasticity of the blank is improved, the deformation resistance is reduced, and the heated raw material is upset on a forging hammer. And a large dependent variable is accumulated in the bearing ring, so that grain refinement is realized, the high-strength characteristic is obtained, the yield strength is greatly improved, the bearing ring is difficult to deform and durable, and the service life of the bearing ring is effectively prolonged.

Description

Technical Field

[0001] The invention belongs to the technical field of bearing processing, and in particular relates to a production process for a high-strength bearing ring. Background Art

[0002] Bearing is an important component in modern mechanical equipment. Its main function is to support the mechanical rotating body, reduce the friction coefficient during its movement, and ensure its rotation accuracy. The production process of bearings mainly includes raw material preparation, inner and outer ring processing, steel ball or roller processing, cage processing and bearing assembly. Among them, key links such as forging, heat treatment and grinding have an important impact on the quality and performance of bearings; bearing rings are annular parts of radial rolling bearings with one or more raceways, which need to be produced and prepared through special bearing ring production processes.

[0003] The existing bearing ring production process cannot produce bearing rings with high strength characteristics, has low yield strength, is easy to deform, has large thermal stress from alternating hot and cold, has large friction, and is prone to thermal fatigue cracks. The overall process steps are relatively complicated, inconvenient to operate, and have poor applicability. Summary of the invention

[0004] The purpose of the present invention is to provide a high-strength bearing ring production process to solve the problems of the existing bearing ring production process proposed in the above background technology, that the bearing rings produced cannot obtain high-strength characteristics, have low yield strength, are easy to deform, have large thermal stress from alternating hot and cold, have large friction, are prone to thermal fatigue cracks, and the overall process steps are relatively complicated, inconvenient to operate, and have poor applicability.

[0005] To achieve the above object, the present invention provides the following technical solution: a high-strength bearing ring production process, the specific production process steps are as follows: Step 1: Select the bar stock for the production of bearing rings, and the inspectors will inspect the bar stock, test the production equipment, and conduct technical briefings to the staff; Step 2: cold-draw the bar through a cold-drawing device to make the outer diameter of the bar the required size of the bearing ring, then axially drill a hole in the cold-drawn bar using a CNC lathe, the hole diameter is the inner diameter of the bearing ring, and then radially cut the bar according to the required size to obtain a blank; Step 3: Before forging, the blank obtained in step 2 is subjected to induction heating treatment to improve its plasticity and reduce deformation resistance. The heated raw material is upset on a forging hammer to form a preliminary ring shape. The upset blank is extruded in a die to form a semi-finished ring that is closer to the final shape. Step 4: The treated semi-finished ring is subjected to constant temperature heat treatment at 800-950°C for 80-130 minutes, sprayed with quenching medium for crystallization annealing for 50-80 minutes, and then unidirectionally rolled for multiple times, with the equivalent effect variable of each unidirectional rolling being 1.5-3; Step 5: Use a high-frequency heating furnace to heat the surface of the workpiece, and heat it at a faster heating rate, generally greater than 600℃ / s, and quickly heat it to 980℃~1100℃. Spray quenching medium on the surface of the heated bearing ring for crystallization annealing for 80~100min. After the insulation is completed, cool it to 145~155℃ with the furnace, and then open the furnace door to cool it to room temperature; Step 6: After quenching, the semi-finished bearing ring is naturally cooled, and a plasma spray gun is used to spray the composite ceramic coating at high temperature. The plasma gas flow H2 flow rate is 2.5L / min, the powder feeding speed is 20g / min, the Ar flow rate is 25L / min, the current is 400A, and the voltage is 50.5V, thereby manufacturing the finished bearing ring; Step 7: Use an industrial camera to photograph the outer surface of the formed bearing ring sample and transmit it to the industrial computer connected to it. The industrial computer is used to compare and analyze the appearance quality of the bearing ring; Step 8: The technician uses the PLC controller to set the working parameters of the press, places the qualified bearing ring sample in step 6 vertically in the fixture, tightens the bolts on both sides to clamp it, turns on the power of the press to drive the punch head to move downward to squeeze the surface of the bearing ring and test its compressive strength.

[0006] Furthermore, in step 1, the inspectors conduct production license inspection on the bar materials. When enterprises purchase imported bar materials that require statutory inspection, they should request valid inspection certificates from suppliers. The relevant indicators of the bar materials must be qualified after self-inspection before they can be put into storage.

[0007] Furthermore, in step six, the bearing ring is pre-sandblasted before coating, the semi-finished bearing ring after sandblasting is ultrasonically cleaned by acetone, and then the surface of the semi-finished bearing ring is sandblasted with 24 mesh brown corundum sand.

[0008] Furthermore, in step six, the composition ratio of chromium oxide, yttrium oxide and aluminum oxide powder in the composite ceramic coating is: 80wt.% chromium oxide powder, 10wt.% yttrium oxide powder and 10wt.% aluminum oxide powder.

[0009] Furthermore, the particle size of the chromium oxide, yttrium oxide and aluminum oxide powder particles is 40 μm to 50 μm, and the thickness of the composite ceramic coating is 220 μm to 280 μm.

[0010] Furthermore, the surface heating temperature in step five should exceed the austenite region temperature range of 723°C to 830°C.

[0011] Furthermore, the quenching medium in step five can be one of water, aqueous solution, emulsion, and oily liquid.

[0012] Compared with the prior art, the present invention has the following beneficial effects: (1) A high-strength bearing ring production process selects bearing ring production bars, and inspectors inspect the bars, conduct trial operation of production equipment, and conduct technical briefings to staff, so that the production of bearing rings is orderly, the fault tolerance rate is reduced, and the quality of products is improved; and the bars are strictly inspected to screen out bars that do not meet the standards, thereby improving the quality of products; the semi-finished rings are quenched and kept warm at 800-950°C and 980-1100°C, respectively, so that a large strain is accumulated in the bearing rings, thereby achieving grain refinement, obtaining high-strength characteristics, greatly improving yield strength, not easy to deform, durable, and effectively extending the service life of the bearing rings.

[0013] (2) A high-strength bearing ring production process. The coating formed by mixing chromium oxide, yttrium oxide and aluminum oxide powder provided by the present invention is tightly bonded, the coating toughness is significantly improved, the thermal stress of hot and cold alternation is low, the friction is small, it is not easy to produce thermal fatigue cracks, and it has the functions of heat insulation and acid and alkali corrosion resistance, thereby improving the performance of the bearing ring. The overall process steps are simple, easy to operate, highly creative, and suitable for wide promotion and use. DETAILED DESCRIPTION

[0014] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0015] A high-strength bearing ring production process, the specific production process steps are as follows: Step 1: Select the bar stock for the production of bearing rings, and the inspectors will inspect the bar stock, test the production equipment, and conduct technical briefings to the staff; Step 2: cold-draw the bar through a cold-drawing device to make the outer diameter of the bar the required size of the bearing ring, then axially drill a hole in the cold-drawn bar using a CNC lathe, the hole diameter is the inner diameter of the bearing ring, and then radially cut the bar according to the required size to obtain a blank; Step 3: Before forging, the blank obtained in step 2 is subjected to induction heating treatment to improve its plasticity and reduce deformation resistance. The heated raw material is upset on a forging hammer to form a preliminary ring shape. The upset blank is extruded in a die to form a semi-finished ring that is closer to the final shape. Step 4: The treated semi-finished ring is subjected to constant temperature heat treatment at 800-950°C for 80-130 minutes, sprayed with quenching medium for crystallization annealing for 50-80 minutes, and then unidirectionally rolled for multiple times, with the equivalent effect variable of each unidirectional rolling being 1.5-3; Step 5: Use a high-frequency heating furnace to heat the surface of the workpiece, and heat it at a faster heating rate, generally greater than 600℃ / s, and quickly heat it to 980℃~1100℃. Spray quenching medium on the surface of the heated bearing ring for crystallization annealing for 80~100min. After the insulation is completed, cool it to 145~155℃ with the furnace, and then open the furnace door to cool it to room temperature; Step 6: After quenching, the semi-finished bearing ring is naturally cooled, and a plasma spray gun is used to spray the composite ceramic coating at high temperature. The plasma gas flow H2 flow rate is 2.5L / min, the powder feeding speed is 20g / min, the Ar flow rate is 25L / min, the current is 400A, and the voltage is 50.5V, thereby manufacturing the finished bearing ring; Step 7: Use an industrial camera to photograph the outer surface of the formed bearing ring sample and transmit it to the industrial computer connected to it. The industrial computer is used to compare and analyze the appearance quality of the bearing ring; Step 8: The technician uses the PLC controller to set the working parameters of the press, places the qualified bearing ring sample in step 6 vertically in the fixture, tightens the bolts on both sides to clamp it, turns on the power of the press to drive the punch head to move downward to squeeze the surface of the bearing ring and test its compressive strength.

[0016] Among them; in the step 1, the inspector conducts production license inspection on the bar material. When enterprises purchase imported bar materials that require statutory inspection, they should request a valid inspection certificate from the supplier. The relevant indicators of the bar materials must be qualified after self-inspection before they can be put into storage.

[0017] Wherein; in the step six, the bearing ring is pre-sandblasted before coating, the semi-finished bearing ring after sandblasting is ultrasonically cleaned by acetone, and then the surface of the semi-finished bearing ring is sandblasted with 24 mesh brown corundum sand.

[0018] Wherein; the composition ratio of chromium oxide, yttrium oxide and aluminum oxide powder in the composite ceramic coating in step six is: 80wt.% chromium oxide powder, 10wt.% yttrium oxide powder, and 10wt.% aluminum oxide powder.

[0019] Wherein, the particle size of the chromium oxide, yttrium oxide and aluminum oxide powder particles is 40 μm to 50 μm, and the thickness of the composite ceramic coating is 220 μm to 280 μm.

[0020] Wherein, the surface heating temperature in step 5 must exceed the austenite region temperature range, i.e., 723°C to 830°C.

[0021] Wherein, the quenching medium in step five can be one of water, aqueous solution, emulsion, and oily liquid.

[0022] When the present invention is working: rods for producing bearing rings are selected, inspectors inspect the rods, and test-run the production equipment, and technical explanations are given to the staff, so that the production of bearing rings is orderly, the fault tolerance rate is reduced, and the quality of products is improved; and the rods are strictly inspected, and rods that do not meet the standards are screened out, thereby improving the quality of products; the semi-finished rings are quenched and kept warm at 800-950°C and 980-1100°C, respectively, so that a large strain is accumulated in the bearing rings, thereby realizing grain refinement, obtaining high-strength characteristics, greatly improving yield strength, not easy to deform, durable, and effectively extending the service life of the bearing rings. The coating formed by mixing chromium oxide, yttrium oxide and aluminum oxide powder provided by the present invention is tightly combined, the toughness of the coating is significantly improved, the thermal stress of hot and cold alternation is low, the friction is small, it is not easy to produce thermal fatigue cracks, and it has the functions of heat insulation and acid and alkali corrosion resistance, thereby improving the performance of the bearing ring. The overall process steps are simple, easy to operate, and highly creative, and suitable for wide promotion and use. The outer surface of the formed bearing ring sample is photographed by an industrial camera and transmitted to an industrial computer connected thereto. The appearance quality of the bearing ring is detected by comparison and analysis through the industrial computer. The technician uses the PLC controller to set the working parameters of the press, and the bearing ring sample that has passed the test in step six is ​​placed vertically in the fixture, and the bolts on both sides are tightened to clamp and fix it. The power of the press is turned on to drive the punch head to move downward to extrude the surface of the bearing ring to detect its compressive strength.

[0023] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A high-strength bearing ring production process, characterized in that: The specific production process steps are as follows: Step 1: Select the bar stock for the production of bearing rings, and the inspectors will inspect the bar stock, test the production equipment, and conduct technical briefings to the staff; Step 2: cold-draw the bar through a cold-drawing device to make the outer diameter of the bar the required size of the bearing ring, then axially drill a hole in the cold-drawn bar using a CNC lathe, the hole diameter is the inner diameter of the bearing ring, and then radially cut the bar according to the required size to obtain a blank; Step 3: Before forging, the blank obtained in step 2 is subjected to induction heating treatment to improve its plasticity and reduce deformation resistance. The heated raw material is upset on a forging hammer to form a preliminary ring shape. The upset blank is extruded in a die to form a semi-finished ring that is closer to the final shape. Step 4: The treated semi-finished ring is subjected to constant temperature heat treatment at 800-950°C for 80-130 minutes, sprayed with quenching medium for crystallization annealing for 50-80 minutes, and then unidirectionally rolled for multiple times, with the equivalent effect variable of each unidirectional rolling being 1.5-3; Step 5: Use a high-frequency heating furnace to heat the surface of the workpiece, and heat it at a faster heating rate, generally greater than 600℃ / s, and quickly heat it to 980℃~1100℃. Spray quenching medium on the surface of the heated bearing ring for crystallization annealing for 80~100min. After the insulation is completed, cool it to 145~155℃ with the furnace, and then open the furnace door to cool it to room temperature; Step 6: After quenching, the semi-finished bearing ring is naturally cooled, and a plasma spray gun is used to spray the composite ceramic coating at high temperature. The plasma gas flow H2 flow rate is 2.5L / min, the powder feeding speed is 20g / min, the Ar flow rate is 25L / min, the current is 400A, and the voltage is 50.5V, thereby manufacturing the finished bearing ring; Step 7: Use an industrial camera to photograph the outer surface of the formed bearing ring sample and transmit it to the industrial computer connected to it. The industrial computer is used to compare and analyze the appearance quality of the bearing ring; Step 8: The technician uses the PLC controller to set the working parameters of the press, places the qualified bearing ring sample in step 6 vertically in the fixture, tightens the bolts on both sides to clamp it, turns on the power of the press to drive the punch head to move downward to squeeze the surface of the bearing ring and test its compressive strength.

2. A high-strength bearing ring production process according to claim 1, characterized in that: In the above step 1, the inspectors conduct production license inspection on the bar materials. When enterprises purchase imported bar materials that require statutory inspection, they should request valid inspection certificates from suppliers. The relevant indicators of the bar materials must be qualified after self-inspection before they can be put into storage.

3. A high-strength bearing ring production process according to claim 1, characterized in that: In the step six, the bearing ring is pre-sandblasted before coating, the semi-finished bearing ring after sandblasting is ultrasonically cleaned by acetone, and then the surface of the semi-finished bearing ring is sandblasted with 24 mesh brown corundum sand.

4. A high-strength bearing ring production process according to claim 1, characterized in that: In the step six, the composition ratio of chromium oxide, yttrium oxide and aluminum oxide powder in the composite ceramic coating is: 80wt.% chromium oxide powder, 10wt.% yttrium oxide powder, and 10wt.% aluminum oxide powder.

5. A high-strength bearing ring production process according to claim 4, characterized in that: The particle size of the chromium oxide, yttrium oxide and aluminum oxide powder particles is 40 μm to 50 μm, and the thickness of the composite ceramic coating is 220 μm to 280 μm.

6. A high-strength bearing ring production process according to claim 1, characterized in that: The surface heating temperature in step 5 should exceed the austenite region temperature range, i.e., 723°C to 830°C.

7. A high-strength bearing ring production process according to claim 1, characterized in that: The quenching medium in step 5 can be one of water, aqueous solution, emulsion and oily liquid.