Local induction quenching device for grooved axial surface and induction quenching heat treatment method

Abstract

The invention provides a grooved axial surface local induction quenching device and an induction quenching heat treatment method. The device comprises a reinforcing structure, an inductor main body and a water sprayer, and the inductor main body and the water sprayer are combined into an integral structure of the local induction quenching device through the reinforcing structure; the inductor main body is used for rapidly heating the grooved axial surface of the crank arm by heat energy converted from magnetic energy, so that the surface of the crank arm is subjected to structure transformation; the water sprayer is used for spraying water to cool the crank arm. According to the magnetic induction principle of a high-energy magnetic line of force at the output end of medium-frequency induction equipment, the grooved axial surface of the crank arm is rapidly heated by heat energy converted from magnetic energy in magnetic circulating current formed under the guidance of an inductor, and quenching and tempering of the grooved axial surface of the crank arm are completed by controlling parameters such as working voltage and heating time; and the hardness, the hardening layer depth and the structure meeting the design requirements are obtained.

Description

Technical Field

[0001] This invention belongs to the field of heat treatment technology for key vehicle components, specifically relating to a grooved shaft surface local induction hardening device and an induction hardening heat treatment method. Background Technology

[0002] The articulated boom is a crucial component of the idler wheel and track adjuster in tracked vehicles, playing a vital role in vehicle steering control. This part is used frequently; to increase the service life of the articulated boom, the design requires a Φ118 shaft surface with an R6.5 groove and a hardness value ≥HRC52, with a groove depth of 3.5~6mm, to enhance its wear resistance. Figure 1 As shown.

[0003] While single-axis induction hardening is a mature process, the presence of the R6.5 groove at the quenching location of the curved arm causes a diameter change. Conventional coil heating methods cannot heat the surface of the R6.5 groove to the required depth on the Φ118 axis, or the depth on the Φ118 axis is significantly out of tolerance when heating within the R6.5 groove. Therefore, a local induction hardening device and method for grooved axis curved arms are needed. This method combines rotation with induction heating to meet the design hardness and depth requirements, enabling the part to achieve localized wear resistance. Summary of the Invention

[0004] (a) Technical problems to be solved This invention proposes a local induction hardening device and a method for induction hardening heat treatment of grooved shaft surfaces, in order to solve the technical problem of obtaining the same range of hardened layer depth after local hardening of the Φ118 shaft surface with R6.5 groove to enhance wear resistance.

[0005] (II) Technical Solution To address the aforementioned technical problems, this invention proposes a local induction hardening device for grooved shaft surfaces. The device includes a reinforcing structure, an inductor body, and a water sprayer. The inductor body and the water sprayer are combined through the reinforcing structure to form the overall structure of the local induction hardening device. The inductor body is used to rapidly heat the grooved shaft surface of the crank arm using thermal energy converted from magnetic energy, causing a structural transformation on the crank arm surface. The water sprayer is used to cool the crank arm by spraying water.

[0006] Furthermore, the sensor includes a quick-connect fitting for the water pipes, a first water pipe, a second water pipe, a third water pipe, a fourth water pipe, a fifth water pipe, a first sensing tube, a second sensing tube, a third sensing tube, a clamp, and a magnetic conductor; wherein, two third water pipes are arranged horizontally side by side and isolated in the middle by an insulating plate; one end of each third water pipe is connected to a vertically arranged second water pipe, and the top end of each second water pipe is connected to the short side of an L-shaped first water pipe, the short sides of the two first water pipes are inclined at an included angle, and the long sides are arranged horizontally at intervals; each first water pipe is equipped with a... It has a quick-connect coupling for the water pipes with sensors; the other end of each third water pipe is connected to a horizontally arranged arc-shaped fourth water pipe, the other end of the fourth water pipe is connected to a vertically arranged first sensing tube, the bottom end of the first sensing tube is connected to a horizontally arranged arc-shaped fifth water pipe, the other end of the fifth water pipe is connected to a vertically arranged second sensing tube, and the top ends of the two second sensing tubes are connected together to a horizontally arranged arc-shaped third sensing tube; the upper and lower ends of the four sets of magnetic conductors are fixed by clamps and respectively glued to the two corresponding first sensing tubes and two second sensing tubes.

[0007] Furthermore, the two third water pipes are separated by an insulating plate.

[0008] Furthermore, connecting plates and reinforcing plates are respectively installed at the connection points on the inner and outer sides of the second and third water pipes.

[0009] Furthermore, the water sprayer includes a quick-connect coupling for the water sprayer's water inlet pipe, a water inlet pipe, and a water sprayer body; wherein, the water sprayer body is fixed to the relative position with the sensor by a reinforcing structure; a water inlet pipe is fixed on the water sprayer body, and a quick-connect coupling for the water sprayer's water inlet pipe is connected to the top of the water inlet pipe.

[0010] Furthermore, two water injection pipes arranged at intervals above and below are fixed on the main body of the water sprayer.

[0011] Furthermore, the two water injection pipes are arranged at an angle.

[0012] Furthermore, this invention also proposes a method for local induction hardening heat treatment of grooved shaft surfaces, employing the aforementioned local induction hardening device for grooved shaft surfaces, comprising the following steps: S1. Installation and positioning of the curved arm and local induction hardening device: Secure the curved arm stably between the upper and lower centers of the induction hardening machine tool, clamp the upper and lower centers tightly, and maintain the balance of the curved arm during rotation. S2. Execute the medium-frequency quenching process: The machine tool center rotates, driving the curved arm to rotate; the inductor is positioned from the initial position to the induction heating position, with the arc surface of the inductor at the grooved induction part maintaining a gap with the inner arc surface of the groove on the curved arm, and the magnetic conductor of the inductor at the axial surface maintaining a gap with the axial surface; after the medium-frequency induction equipment is connected to the power supply voltage, the working voltage is adjusted so that the inductor outputs high-energy magnetic lines. Utilizing the magnetic induction principle of the high-energy magnetic lines at the output of the medium-frequency induction equipment, high-intensity magnetic energy is converted into high-intensity heat energy in the magnetic current formed under the guidance of the inductor. The heat energy converted from magnetic energy is concentrated on the grooved axial surface of the curved arm for heating. The grooved axial surface of the curved arm is heated in a continuous heating mode, causing a structural transformation on the surface of the curved arm; heating is stopped, and the curved arm is cooled by spraying water through a water sprayer, rotation is stopped, and the inductor is positioned back to the initial position; S3. Low-temperature tempering: After the curved arm is cooled, it is tempered at a low temperature.

[0013] Further, in step S1, the machine tool rotation speed is 30 r / min; in step S2, the gap between the arc surface of the sensor in the groove sensing part and the inner arc surface of the groove on the curved arm is 2.5 mm, and the gap between the magnetic conductor of the sensor in the shaft surface part and the shaft surface is 2.5 mm; the continuous heating time is 20 s; the cooling water temperature is 20~40℃, and the water spraying duration is 80 s.

[0014] Furthermore, in step S3, low-temperature tempering is carried out within a period not exceeding 24 hours, with a tempering holding temperature of 160±20℃ and a holding time of 120~150min.

[0015] (III) Beneficial Effects This invention proposes a local induction hardening device and method for grooved shaft surfaces. The device includes a reinforcing structure, an inductor body, and a water sprayer. The inductor body and the water sprayer are combined into a single structure by the reinforcing structure. The inductor body is used to rapidly heat the grooved shaft surface of the crank arm using thermal energy converted from magnetic energy, causing a microstructural transformation on the crank arm surface. The water sprayer is used to cool the crank arm with water. This invention utilizes the magnetic induction principle of high-energy magnetic lines of force at the output of a medium-frequency induction device. Under the guidance of the inductor, the grooved shaft surface of the crank arm is rapidly heated using thermal energy converted from magnetic energy in a magnetic circulation. By controlling parameters such as the working voltage and heating time, the quenching and tempering of the grooved shaft surface of the crank arm are completed, obtaining the hardness, hardened layer depth, and microstructure that meet the design requirements. This invention can simultaneously and efficiently complete the quenching process of different diameter parts of the grooved shaft surface of the crank arm, improving the hardness of the grooved shaft surface to HRC52 or higher, enhancing the wear resistance of the grooved shaft surface, and the process method is safe, applicable, simple to operate, economical, efficient, and produces products with high precision. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the articulated arm structure to which this invention applies; Figure 2a This is a front view of the grooved shaft surface local induction hardening device of the present invention. Figure 2b This is a top view. Figure 2c It is a bottom view. Figure 2d Left view, Figure 2e Right view; Figure 3a This is a front view of the sensor structure in this invention. Figure 3b This is a top view. Figure 3c Left view; Figure 4a This is a front view of the water sprayer structure in this invention. Figure 4b Left view, Figure 4c This is a right-side sectional view; Figure 5 This is a schematic diagram showing the contact between the local induction hardening device of the present invention and the grooved shaft surface of the curved arm. Detailed Implementation

[0017] To make the objectives, contents, and advantages of the present invention clearer, the specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples.

[0018] This embodiment proposes a device for local induction hardening of grooved shaft surfaces, the overall structure of which is as follows: Figures 2a-2e As shown, it mainly includes a reinforcing structure 1, an inductor body 2, and a water sprayer 3. The inductor body 2 and the water sprayer 3 are welded together through the reinforcing structure 1 to form the overall structure of the local induction hardening device. The inductor body 2 is used to rapidly heat the grooved shaft surface of the crank arm using heat energy converted from magnetic energy, causing a rapid microstructural transformation on the crank arm surface. The water sprayer 3 is used to cool the crank arm with water.

[0019] like Figures 3a-3cAs shown, sensor 2 mainly includes a sensor water pipe quick-connect connector 2-1, a first water pipe 2-2, a second water pipe 2-3, a connecting plate 2-4, a reinforcing plate 2-5, a third water pipe 2-6, a fourth water pipe 2-7, a first sensing tube 2-8, a clamping plate 2-9, a fifth water pipe 2-10, a second sensing tube 2-11, a magnetic conductor 2-12, a third sensing tube 2-13, and an insulating plate 2-14. Two third water pipes 2-6 are arranged horizontally side-by-side and isolated in the middle by the insulating plate 2-14. One end of each third water pipe 2-6 is connected to a vertically arranged second water pipe 2-3, and the top of each second water pipe 2-3 is connected to the short side of an L-shaped first water pipe 2-2. The short sides of the two first water pipes 2-2 are inclined at a certain angle, and their long sides are horizontally spaced at a certain distance. A sensor water pipe quick-connect connector 2-1 is installed at the end of each first water pipe 2-2. Connecting plates 2-4 and reinforcing plates 2-5 are respectively installed at the inner and outer connections of the second water pipe 2-3 and the third water pipe 2-6. The other end of each third water pipe 2-6 is connected to a horizontally arranged arc-shaped fourth water pipe 2-7. The other end of the fourth water pipe 2-7 is connected to a vertically arranged first sensing tube 2-8. The bottom end of the first sensing tube 2-8 is connected to a horizontally arranged arc-shaped fifth water pipe 2-10. The other end of the fifth water pipe 2-10 is connected to a vertically arranged second sensing tube 2-11. A horizontally arranged arc-shaped third sensing tube 2-13 is connected between the top ends of the two second sensing tubes 2-11. The upper and lower ends of the four sets of magnetic conductors 2-12 are fixed by clamps 2-9 and glued to the corresponding two first sensing tubes 2-8 and two second sensing tubes 2-11.

[0020] like Figures 4a-4c As shown, the water sprayer 3 mainly includes a quick-connect coupling 3-1 for the water sprayer's water inlet pipe, a water inlet pipe 3-2, and a water sprayer body 3-3. The water sprayer bodies 3-3 of the two water sprayers 3 are fixed to the relative position of the sensor 2 by a reinforcing structure 1. Two inclined water inlet pipes 3-2, arranged vertically at intervals, are welded onto the water sprayer body 3-3, and the top end of each water inlet pipe 3-2 is connected to the quick-connect coupling 3-1 for the water sprayer's water inlet pipe.

[0021] The method for local induction hardening heat treatment using the above-mentioned grooved shaft surface local induction hardening device specifically includes the following steps: S1. Installation and positioning of the curved arm and local induction hardening device: Secure the curved arm stably between the upper and lower centers of the induction hardening machine tool, clamp the upper and lower centers tightly, and maintain the balance of the curved arm during rotation.

[0022] S2. Execute the medium-frequency quenching process: The machine tool center rotates, driving the crank arm to rotate at a speed of 30 r / min; Inductor 2 is positioned from its initial position to the induction heating position. The gap between the arc surface of inductor 2 at the groove induction part and the inner arc surface of the R6.5 groove on the crank arm is 2.5 mm, and the gap between the magnetic conductor 2-12 of the inductor at the shaft surface and the shaft surface is 2.5 mm; After the medium-frequency induction equipment is connected to a 380V power supply, the working voltage is adjusted to 260±10V to make the inductor output high-energy magnetic lines, utilizing the medium-frequency induction... Based on the magnetic induction principle of the high-energy magnetic lines at the output end of the equipment, the high-intensity magnetic energy is instantly converted into high-intensity heat energy in the magnetic loop formed under the guidance of sensor 2. The heat energy converted from magnetic energy is concentrated on the grooved shaft surface of the crank arm for heating, and the grooved shaft surface of the crank arm is heated rapidly. The continuous heating mode is adopted, and the heating time is 20 seconds, so that the surface of the crank arm undergoes rapid tissue transformation. Heating is stopped, and water is sprayed onto the crank arm for cooling through water sprayer 3. The cooling water temperature is 20~40℃, and the water spraying time is 80 seconds. Rotation stops, and sensor 2 is positioned at the initial position.

[0023] During implementation, when the sensor is positioned at the heating location, its relative position to the grooved shaft surface of the crank arm is as follows: Figure 5 As shown, the magnetic conductor 2-12 for heating the Φ118 axial surface is made of a 14mm square copper tube, and the third induction tube 2-13 for heating the R6.5 groove surface is made of a Φ8 copper tube, with the Φ8 copper tube extending into the R6.5 groove. The gap between the sensing part of the induction unit 2 (the third induction tube 2-13) and the surface of the R6.5 groove, and between the magnetic conductor 2-12 and the Φ118 axial surface, is 2.5mm. When the crank arm rotates under the control of the upper and lower centers, the relative position of the induction unit 2 and the crank arm remains unchanged, causing the surface of the crank arm to be rapidly heated in the magnetic circulation, resulting in a structural transformation. After being rapidly cooled by the water spray from the water sprayer 3, a martensitic structure is obtained. After the water sprayer 3 stops spraying water, the crank arm stops rotating, and the induction unit is positioned at its initial position, which is >200mm from the heating position, facilitating the disassembly of the crank arm.

[0024] S3. Low-temperature tempering: After the curved arm is cooled, it should be promptly placed into a box-type or pit-type resistance furnace for low-temperature tempering within 24 hours (8 hours in this embodiment). The tempering holding temperature is 160±20℃ and the holding time is 120~150min.

[0025] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A device for local induction hardening of grooved shaft surfaces, characterized in that, The grooved shaft surface local induction hardening device includes a reinforcing structure, an inductor body, and a water sprayer; wherein, the inductor body and the water sprayer are combined by the reinforcing structure to form the overall structure of the local induction hardening device; the inductor body is used to rapidly heat the grooved shaft surface of the crank arm with the thermal energy converted from magnetic energy, so that the surface of the crank arm undergoes a structural transformation; the water sprayer is used to spray water to cool the crank arm.

2. The grooved shaft surface local induction hardening device as described in claim 1, characterized in that, The sensor includes a quick-connect water pipe connector, a first water pipe, a second water pipe, a third water pipe, a fourth water pipe, a fifth water pipe, a first sensing tube, a second sensing tube, a third sensing tube, a clamp, and a magnetic conductor; wherein, two third water pipes are arranged horizontally side by side and isolated in the middle by an insulating plate; one end of each third water pipe is connected to a vertically arranged second water pipe, and the top end of each second water pipe is connected to the short side of an L-shaped first water pipe, the short sides of the two first water pipes are inclined at an included angle, and the long sides are arranged horizontally at intervals; each first water pipe is equipped with a... The sensor water pipe quick-change connector; the other end of each third water pipe is connected to a horizontally arranged arc-shaped fourth water pipe, the other end of the fourth water pipe is connected to a vertically arranged first sensing tube, the bottom end of the first sensing tube is connected to a horizontally arranged arc-shaped fifth water pipe, the other end of the fifth water pipe is connected to a vertically arranged second sensing tube, and the top ends of the two second sensing tubes are connected together to a horizontally arranged arc-shaped third sensing tube; the upper and lower ends of the four sets of magnetic conductors are fixed by clamps and respectively glued to the corresponding two first sensing tubes and two second sensing tubes.

3. The grooved shaft surface local induction hardening device as described in claim 2, characterized in that, The two third water pipes are separated by an insulating plate.

4. The grooved shaft surface local induction hardening device as described in claim 2, characterized in that, Connecting plates and reinforcing plates are respectively installed at the inner and outer ends of the second and third water pipes.

5. The grooved shaft surface local induction hardening device as described in claim 2, characterized in that, The water sprayer includes a quick-connect coupling for the water sprayer's water inlet pipe, a water inlet pipe, and a water sprayer body; wherein, the water sprayer body is fixed to the relative position with the sensor by a reinforcing structure; a water inlet pipe is fixed on the water sprayer body, and a quick-connect coupling for the water sprayer's water inlet pipe is connected to the top of the water inlet pipe.

6. The grooved shaft surface local induction hardening device as described in claim 5, characterized in that, The water sprayer body is fixed with two water injection pipes arranged at intervals.

7. The grooved shaft surface local induction hardening device as described in claim 6, characterized in that, The two water injection pipes are arranged at an angle.

8. A method for local induction hardening heat treatment of a grooved shaft surface, characterized in that, The grooved shaft surface local induction hardening apparatus according to any one of claims 1 to 7, wherein the grooved shaft surface local induction hardening heat treatment method comprises the following steps: S1. Installation and positioning of the curved arm and local induction hardening device: Secure the curved arm stably between the upper and lower centers of the induction hardening machine tool, clamp the upper and lower centers tightly, and maintain the balance of the curved arm during rotation. S2. Execute the medium-frequency quenching process: The machine tool center rotates, driving the curved arm to rotate; the inductor is positioned from the initial position to the induction heating position, with the arc surface of the inductor at the grooved induction part maintaining a gap with the inner arc surface of the groove on the curved arm, and the magnetic conductor of the inductor at the axial surface maintaining a gap with the axial surface; after the medium-frequency induction equipment is connected to the power supply voltage, the working voltage is adjusted so that the inductor outputs high-energy magnetic lines. Utilizing the magnetic induction principle of the high-energy magnetic lines at the output of the medium-frequency induction equipment, high-intensity magnetic energy is converted into high-intensity heat energy in the magnetic current formed under the guidance of the inductor. The heat energy converted from magnetic energy is concentrated on the grooved axial surface of the curved arm for heating. The grooved axial surface of the curved arm is heated in a continuous heating mode, causing a structural transformation on the surface of the curved arm; heating is stopped, and the curved arm is cooled by spraying water through a water sprayer, rotation is stopped, and the inductor is positioned back to the initial position; S3. Low-temperature tempering: After the curved arm is cooled, it is tempered at a low temperature.

9. The method for local induction hardening heat treatment of grooved shaft surfaces as described in claim 8, characterized in that, In step S1, the machine tool rotation speed is 30 r / min; in step S2, the gap between the arc surface of the sensor in the groove sensing part and the inner arc surface of the groove on the curved arm is 2.5 mm, and the gap between the magnetic conductor of the sensor in the shaft surface part and the shaft surface is 2.5 mm; the continuous heating time is 20 s; the cooling water temperature is 20~40℃, and the water spraying duration is 80 s.

10. The method for local induction hardening heat treatment of grooved shaft surfaces as described in claim 8, characterized in that, In step S3, low-temperature tempering is carried out within a period not exceeding 24 hours, with a tempering holding temperature of 160±20℃ and a holding time of 120~150min.

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