A warm forging process method of 8Cr4Mo4V steel ball

Abstract

The application discloses a warm forging process method of 8Cr4Mo4V steel ball, and belongs to the technical field of steel ball production. The application solves the problems existing in the prior art. The method comprises the following steps: firstly, placing a 8Cr4Mo4V steel material section on a rotating feeding disc, and transferring the material section to a rotary bottom type forging heating furnace through a mechanical hand R1; secondly, taking the material section out of the furnace after heat preservation, transferring the material section to an electric screw press through the mechanical hand R1, and performing warm forging forming; thirdly, slowly cooling the forged steel ball, and collecting the slowly cooled steel ball. In the application, a steel ball warm forging automatic production line is adopted, a 8Cr4Mo4V steel ball precision warm forging forming process is formulated, the ring belt size is reduced, the influence of human factors is reduced, the size precision and quality consistency of the steel ball are improved, the appearance, size, grain size and other items of the steel ball meet the requirements of relevant standards, and the warm forging precision forming of steel balls with different sizes can be realized. The application is suitable for the warm forging process of 8Cr4Mo4V steel balls.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of steel ball production, and particularly relates to a warm forging process method of 8Cr4Mo4V steel ball. BACKGROUND

[0002] The existing aviation bearing steel ball heating adopts a box-type resistance furnace, manual loading and taking materials, 10-12 steel ball blanks are loaded per tray, and the steel ball blanks are heated in the furnace (10-12 trays per furnace) and taken out one by one for forging forming, the heating time is prolonged one by one, and different holding times lead to poor consistency of the steel ball quality.

[0003] The forming equipment of the steel ball hot forging process is relatively backward, the positioning precision is low, the skill proficiency and cooperation of the operator are required to be high, the ring belt of the forged steel ball is relatively high, Figure 1 after the ring belt is ground, the internal metal flow line of the steel ball is broken, Figure 2 cracks are easily formed at the metal fracture in the high-speed running state of the bearing, and the bearing is failed. SUMMARY

[0004] The application aims to solve the above problems, and provides a warm forging process method of 8Cr4Mo4V steel ball; the warm forging automatic production line of the steel ball is adopted, the precise warm forging forming process of the 8Cr4Mo4V steel ball is formulated, the ring belt size is reduced, the influence of human factors is reduced, and the size precision and quality consistency of the steel ball are improved.

[0005] A warm forging process method of 8Cr4Mo4V steel ball, which is performed according to the following steps:

[0006] I. The 8Cr4Mo4V steel material section is placed on a rotating feeding tray, is transferred to a rotary bottom forging heating furnace by a mechanical hand R1, the temperature is 950-980 DEG C, the heat penetration coefficient is 1.5-2.0 min / mm, and the holding time is 20-30 min;

[0007] II. After the above holding is finished, the furnace is discharged, the mechanical hand R1 is transferred to an electric screw press, warm forging forming is performed, and the temperature of the forged steel ball is ensured to be greater than 750 DEG C, then the mechanical hand R2 is transferred to a slow cooling machine;

[0008] III. The slow cooling machine adopts two-zone temperature control, and the temperatures are 600 DEG C and 400 DEG C respectively, the temperature of the steel ball after passing through the slow cooling machine is ensured to be less than or equal to 200 DEG C, the slow cooling of the forged steel ball is completed, and the slow cooled steel ball flows to a collecting tray for centralized collection, and the warm forging process method is completed.

[0009] Further, the stroke of the electric screw press in step II is set to be less than or equal to 0.5 mm between the upper and lower molds; and an infrared temperature measuring device is installed on the electric screw press.

[0010] Further, the pressure of the warm forging forming in step two is 630 tons.

[0011] Further, the slow cooling machine in step three is a roller bottom type three-stage cooling slow cooling machine, and the temperature of two zones is controlled, and one zone is naturally cooled.

[0012] The beneficial effects of the present application are:

[0013] In the present application, a steel ball warm forging automatic production line is adopted, and an 8Cr4Mo4V steel ball precision warm forging forming process is formulated, so that the ring belt size is reduced, the influence of human factors is reduced, the steel ball size precision and quality consistency are improved, and the steel ball appearance, size, grain size and other items meet the requirements of relevant standards.

[0014] In the present application, the warm forging process of the 8Cr4Mo4V steel ball is integrated with the production line control to form a steel ball warm forging automatic production line, so that the warm forging precision forming of steel balls of different sizes can be realized.

[0015] The present application is suitable for the warm forging process of the 8Cr4Mo4V steel ball. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 It is a steel ball blank physical map after existing steel ball forging in the present application;

[0017] Figure 2 It is a steel ball streamline physical map after existing steel ball forging and grinding off the ring belt in the present application;

[0018] Figure 3 It is a schematic diagram of the steel ball warm forging automatic production line in the present application;

[0019] Figure 4 It is a physical map of the steel ball ring belt detection after warm forging in the embodiment. DETAILED DESCRIPTION

[0020] The technical scheme of the present application is not limited to the following specific embodiments, and also includes any combination of the specific embodiments.

[0021] Specific embodiment one: the warm forging process method of the 8Cr4Mo4V steel ball in this embodiment is carried out according to the following steps:

[0022] I. Put the 8Cr4Mo4V steel material section on the rotating feeding disc, transfer it to the rotary bottom forging heating furnace through the mechanical hand R1, the temperature is 950-980 DEG C, the heat penetration coefficient is 1.5-2.0 min / mm, and the holding time is 20-30 min;

[0023] II. After the above heat preservation is finished, the furnace is discharged, transferred to an electric screw press by a robot R1, warm forging is performed, and the temperature of the forged steel ball is ensured to be >750℃, then transferred to a slow cooling machine by a robot R2;

[0024] III. The slow cooling machine adopts two-zone temperature control, which is 600℃ and 400℃ respectively, and the temperature of the steel ball after passing through the slow cooling machine is ensured to be >200℃, the slow cooling of the forged steel ball is completed, and the slow cooled steel ball flows to a collection tray for centralized collection, i.e. the warm forging process is completed.

[0025] In step one of the embodiment, a 8Cr4Mo4V steel material section is taken according to the actual design requirement.

[0026] In the embodiment, the feeding tray, the robot R1, the rotary bottom forging heating furnace, the electric screw press, the robot R2, the slow cooling machine and the collection tray are combined with the production line integrated control to form a steel ball warm forging automatic production line.

[0027] Specific implementation method two: different from the specific implementation method one, the temperature in step one is 960℃, the hot penetration coefficient is 1.8min / mm, and the heat preservation time is 25min. The other steps and parameters are the same as those in the specific implementation method one.

[0028] Specific implementation method three: different from the specific implementation method one, the stroke of the electric screw press in step two is set to be >0.5mm between the upper and lower molds; the infrared temperature measuring device is installed on the electric screw press. The other steps and parameters are the same as those in the specific implementation method one.

[0029] Specific implementation method four: different from the specific implementation method one, the warm forging forming pressure in step two is 630 tons. The other steps and parameters are the same as those in the specific implementation method one.

[0030] Specific implementation method five: different from the specific implementation method one, the slow cooling machine in step three adopts a roller bottom type three-stage cooling slow cooling machine, two-zone temperature control, and one natural cooling. The other steps and parameters are the same as those in the specific implementation method one.

[0031] The beneficial effects of the present application are verified by the following examples:

[0032] Example:

[0033] A warm forging process method of a 8Cr4Mo4V steel ball, which is performed according to the following steps:

[0034] I. A 8Cr4Mo4V steel material section is placed on a rotary feeding tray, transferred to a rotary bottom forging heating furnace by a robot R1, the temperature is 970℃, the hot penetration coefficient is 1.8min / mm, and the heat preservation time is 25min;

[0035] II. After the above heat preservation is finished, the steel ball is transferred to an electric screw press by a robot R1, warm forging is performed, and the temperature of the steel ball after forging is ensured to be >750°C, then the steel ball is transferred to a slow cooling machine by a robot R2;

[0036] III. The slow cooling machine is controlled at two temperatures, 600°C and 400°C, respectively, to ensure that the temperature of the steel ball after passing through the slow cooling machine is >200°C, the slow cooling of the steel ball after forging is completed, and the steel ball after slow cooling flows to a collection tray for centralized collection, i.e., the warm forging process is completed.

[0037] In step II of the embodiment, the stroke of the electric screw press is set to be >0.5mm between the upper and lower molds; and an infrared temperature measuring device is installed on the electric screw press.

[0038] In step II of the embodiment, the pressure of the warm forging is 630 tons.

[0039] In step III of the embodiment, the slow cooling machine is a roller bottom type three-stage cooling slow cooling machine, and is controlled at two temperatures, one of which is natural cooling.

[0040] In the embodiment, the feeding tray, the robot R1, the rotary bottom type forging heating furnace, the electric screw press, the robot R2, the slow cooling machine, and the collection tray are integrated with the production line control to form a steel ball warm forging automatic production line, as shown in Figure 3 .

[0041] Comparison: After the existing steel ball is forged, the ring belt is 1.6mm high, as shown in Figure 1 .

[0042] After the steel ball obtained by the warm forging process in the embodiment is detected, the ring belt is reduced to 0.6mm, as shown in Figure 4 , and the appearance, size, grain size, and other items of the steel ball all meet the requirements of the relevant standards.

Claims

1. A warm forging process of 8Cr4Mo4V steel ball characterized in that It is carried out in the following steps: I. Take 8Cr4Mo4V steel section placed on the rotating feeder, transferred to the rotary bottom forging furnace by mechanical hand R1, the temperature is 950℃-980℃, the heat penetration coefficient is 1.5-2.0min / mm, the holding time is 20-30min; II. After the above holding is finished, it is transferred to the electric screw press by mechanical hand R1, and the temperature of the forged steel ball is greater than 750℃ after warm forging, and then it is transferred to the slow cooling machine by mechanical hand R2; III. The above slow cooling machine adopts two zone temperature control, which is 600℃ and 400℃ respectively, to ensure that the temperature of the steel ball after passing through the slow cooling machine is≯200℃, and the slow cooling of the forged steel ball is completed, and the slow cooled steel ball flows to the collection tray for collection, that is, the warm forging process is completed; The stroke of the electric screw press in step II is set to be the distance between the upper and lower molds≯0.5mm; the electric screw press is provided with an infrared temperature measuring device; The pressure of the warm forging in step II is 630 tons; The slow cooling machine in step III adopts a three-stage roller bottom cooling machine with two zone temperature control, and the first zone is naturally cooled.

2. The warm forging process of a 8Cr4Mo4V steel ball according to claim 1, characterized in that The temperature in step I is 960℃, the heat penetration coefficient is 1.8min / mm, and the holding time is 25min.

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