CN102814435B - Method for roll forming spline shaft by medium-frequency and high-frequency sensing heating - Google Patents

Abstract

A method for rolling and forming a spline shaft by medium and high frequency induction heating. First, the workpiece is clamped, and the surface of the spline section at one end of the workpiece is heated. The rolling die completes the forming of the spline, and then the workpiece is turned around and re-clamped. The surface of the forming spline section at the other end is heated, and then the rolling die completes the forming of the spline section, and finally unloads the material. The medium and high frequency induction heater is between the rolling mold and the clamping position of the workpiece. The medium and high frequency induction heater is only for the The local area of the surface where plastic deformation occurs is heated, and the workpiece can be quickly sent to the working area of the rolling die after heating. The invention has the advantages of small spline forming force, energy saving, and can be added to spline parts with large deformation resistance and large modulus. It has the advantages of high precision and surface quality, high production efficiency and wide processing range.

Description

A method for rolling and forming a spline shaft by medium and high frequency induction heating

technical field

The invention belongs to the technical field of advanced material forming, and in particular relates to a method for forming a spline shaft by medium and high frequency induction heating and rolling.

Background technique

The spline is a key part used to transmit force and torque in the mechanical system. As a connection method with high connection strength, compact structure and high reliability, the spline connection is widely used in automobiles, various vehicles and equipment manufacturing industries. .

With the rapid development of the automobile industry, the demand for high-strength and high-precision splines is increasing and the requirements for use are constantly improving, which poses new challenges to the processing technology and equipment of traditional splines. Spline processing technology is mainly divided into traditional cutting and plastic forming processing. The traditional spline cutting process has the disadvantages of high cutting strength, low productivity, poor mechanical properties and surface quality, while the spline roll forming process has no In the field of chip processing, it has many advantages such as high production efficiency, high material utilization rate, small forming load, stable workpiece dimensional accuracy, and good product performance. It is widely used in involute spline processing and manufacturing. However, the deformation resistance of high-strength steel at room temperature is large, which makes the forming load of high-strength steel spline cold rolling large, the material flow is difficult, and the transmission system and overall rigidity of the forming equipment are also faced with great challenges.

Warm forming combines the advantages of cold forming and hot forming, which can not only effectively reduce the deformation resistance and improve the plastic forming ability of metal materials, but also avoid the large energy consumption of hot forming, which is prone to overheating, oxidation, decarburization, and large processing allowance and other shortcomings; can obtain better product surface quality and higher dimensional accuracy. At present, due to the many advantages of warm forming, many scholars have carried out extensive research on this process, which has been applied to many production occasions and achieved satisfactory results, such as warm deep drawing forming, warm extrusion forming, warm forging precision forming, etc., but The warm forming technology has not been applied to the plastic working process of spline rolling.

Contents of the invention

In order to overcome the shortcomings of the above-mentioned prior art, the object of the present invention is to provide a method for forming a spline shaft by medium and high frequency induction heating and rolling, which has small spline forming load, good material flow performance, and can process materials with large deformation resistance and large modulus Spline parts have the advantages of high forming accuracy and surface quality, high production efficiency, wide processing range and strong versatility.

In order to achieve the above object, the technical scheme that the present invention takes is:

A method for rolling and forming a spline shaft by medium and high frequency induction heating, comprising the following steps:

Step 1, clamp the workpiece 2, the workpiece 2 is clamped by the front top 1 and the rear top 3, so that the axis of the workpiece 2 is on the same level as the axis of the two rolling dies 5, and the axes of the two rolling dies 5 are parallel and symmetrical Distributed on both sides of the workpiece 2, the forming spline section a on the workpiece 2 is close to the rolling die 5;

Step 2, the surface of the formed spline section a on the workpiece 2 is locally heated, specifically:

2.1. The workpiece 2 is fed in the direction of the rolling die 5, and the formed spline section a on the workpiece 2 enters the medium and high frequency induction heater 4, and the medium and high frequency induction heater 4 is arranged at the clamping position of the extrusion rolling die 5 and the workpiece 2 Between, the length of the medium and high frequency induction heater 4 along the axial direction is not less than the length of the spline section a;

2.2. The medium and high frequency induction heater 4 starts to work, and the surface heating layer depth Δ of the formed spline section a on the workpiece 2 should satisfy the formula: Δ=r _Z -r _f +(1.5~2.0)h;

In the formula: r _Z is the radius of the billet before rolling in the spline area of the billet; r _f is the root circle radius of the formed spline; h is the overall height of the formed spline teeth;

2.3. The temperature within the depth Δ of the surface heating layer of the formed spline section a on the workpiece 2 reaches the predetermined forming temperature T, and the medium and high frequency induction heater 4 stops working. The forming temperature T is above the temperature of the blue brittle zone of the deformed material, and the process is fully carried out. Warm forming temperature below the recrystallization temperature; or hot forming temperature above the sufficient recrystallization temperature;

Step 3, forming the spline section a on the workpiece 2 by rolling and forming the spline, specifically:

The workpiece 2 is fed in the direction of the rolling die 5, the formed spline section a on the workpiece 2 enters the working range of the rolling die 5, the two rolling dies 5 rotate synchronously in the same direction, and the two rolling dies 5 are fed radially at the same time Or no radial feed until the roll forming of the formed spline section a on the workpiece 2 is completed,

When the rolling die 5 is fed radially, the working surface of the rolling die 5 is completely toothed; when the rolling die 5 is not fed radially, the working surface of the rolling die 5 is gradually increased from the toothless part and the tooth height The incomplete tooth shape part and the complete tooth shape part are composed,

The range of peripheral speed at the largest addendum circle of the rolling die 5 is 8-10m/min; the radial feed of the rolling die 5 ranges from 0.05-0.15mm for each revolution of the workpiece 2;

Step 4, the workpiece 2 is clamped by the front center 1 and the rear center 3 and withdraws in reverse direction. If the workpiece 2 has only the formed spline section a, it will be unloaded directly; if the other end of the workpiece 2 has the formed spline section b, Then perform steps 5 to 8;

Step 5, turn workpiece 2 around, re-clamp workpiece 2,

The workpiece 2 is clamped by the front top 1 and the rear top 3, so that the axis of the workpiece 2 is on the same level as the axes of the two rolling dies 5, and the axes of the two rolling dies 5 are parallel and symmetrically distributed on both sides of the workpiece 2. 2. The upper forming spline segment b is close to the rolling die 5;

Step 6, the surface of the formed spline section b on the workpiece 2 is locally heated, specifically:

6.1. The workpiece 2 is fed in the direction of the rolling die 5, and the formed spline section b on the workpiece 2 enters the medium and high frequency induction heater 4, and the medium and high frequency induction heater 4 is arranged at the clamping position of the extrusion rolling die 5 and the workpiece 2 Between, the length of the medium and high frequency induction heater 4 along the axial direction is not less than the length of the spline segment b;

6.2. The medium and high frequency induction heater 4 starts to work, and the surface heating layer depth Δ of the formed spline section b on the workpiece 2 should satisfy the formula Δ=r _Z -r _f +(1.5~2.0)h;

6.3. When the temperature within the depth Δ of the surface heating layer of the formed spline section b on the workpiece reaches the predetermined forming temperature T, the medium and high frequency induction heater 4 stops working, and the forming temperature T is above the temperature of the blue brittle zone of the deformed material. Warm forming temperature below the crystallization temperature; or hot forming temperature above the temperature for sufficient recrystallization;

Step 7, the formed spline section b on the workpiece 2 is rolled to form the spline, specifically:

The workpiece 2 is fed in the direction of the rolling die 5, the formed spline section b on the workpiece 2 enters the working range of the rolling die 5, the two rolling dies 5 rotate synchronously in the same direction, and the two rolling dies 5 are fed radially at the same time Or no radial feed until the roll forming of the formed spline segment b on the workpiece 2 is completed,

When the rolling die 5 is fed radially, the working surface of the rolling die 5 is completely toothed; when the rolling die 5 is not fed radially, the working surface of the rolling die 5 is gradually increased from the toothless part and the tooth height The incomplete tooth shape part and the complete tooth shape part are composed,

The range of peripheral speed at the largest addendum circle of the rolling die 5 is 8-10m/min; the radial feed of the rolling die 5 ranges from 0.05-0.15mm for each revolution of the workpiece 2;

Step 8, the workpiece 2 is clamped by the front center 1 and the rear center 3 and withdraws in the reverse direction at the same time, unloading.

The invention organically combines medium-high frequency induction heating with spline rolling forming to realize rolling forming of high-strength steel spline shafts; medium-high frequency induction heaters are placed between the rolling die and the clamping position of the workpiece, and the workpiece can be quickly fed after heating To the working area of the rolling die; the medium and high frequency induction heater only heats the local area of the surface that will undergo plastic deformation, saving energy; it can reduce the deformation resistance of the material and improve the plastic deformation capacity of the metal; the material can be processed with high deformation resistance and large modulus flowers key.

Description of drawings

Fig. 1 is a flowchart of the present invention.

Fig. 2 is a schematic diagram of connection of devices used in the present invention.

FIG. 3 is a schematic diagram of the layout and movement of the workpiece 2 and the rolling die 5 according to Embodiment 1 of the present invention.

Fig. 4 is a schematic diagram of the blank structure of Embodiment 1 of the present invention.

Fig. 5 is a schematic diagram of the layout and movement of the workpiece 2 and the rolling die 5 according to the second embodiment of the present invention.

Fig. 6 is a schematic diagram of the blank structure of Embodiment 2 of the present invention.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

Embodiment one

Both ends of the formed workpiece 2 in this embodiment have formed spline segments, and the material of the workpiece 2 is 42CrMo high-strength steel; the two rolling dies 5 rotate synchronously in the same direction, and the two rolling dies 5 are fed radially at the same time.

Referring to Fig. 1, a method for rolling and forming a spline shaft by medium and high frequency induction heating includes the following steps:

Step 1, clamp the workpiece 2, the workpiece 2 is clamped by the front top 1 and the rear top 3, so that the axis of the workpiece 2 is on the same level as the axis of the two rolling dies 5, and the axes of the two rolling dies 5 are parallel and symmetrical Distributed on both sides of the workpiece 2, the forming spline section a on the workpiece 2 is close to the rolling die 5;

Step 2, the surface of the formed spline section a on the workpiece 2 is locally heated, specifically:

2.1. The workpiece 2 is fed in the direction of the rolling die 5, and the formed spline section a on the workpiece 2 enters the medium and high frequency induction heater 4. Referring to Figure 2, the medium and high frequency induction heater 4 is extruded between the rolling die 5 and the workpiece 2. Between the clamping positions, the axial length of the medium and high frequency induction heater 4 is not less than the length of the spline section a;

2.2. The medium and high frequency induction heater 4 starts to work, and the surface heating layer depth Δ of the formed spline section a on the workpiece 2 should satisfy the formula Δ=r _Z -r _f +(1.5~2.0)h;

In the formula: r _Z is the radius of the billet before rolling in the spline area of the billet; r _f is the root circle radius of the formed spline; h is the overall height of the formed spline teeth;

2.3. The temperature within the depth Δ of the surface heating layer of the formed spline section a on the workpiece 2 reaches the predetermined forming temperature T, and the medium and high frequency induction heater 4 stops working. The forming temperature T is above the temperature of the blue brittle zone of the deformed material, and the process is fully carried out. Warm forming temperature below the recrystallization temperature, specifically 700°C;

Step 3, forming the spline section a on the workpiece 2 by rolling and forming the spline, specifically:

The workpiece 2 is fed in the direction of the rolling die 5, the formed spline section a on the workpiece 2 enters the working range of the rolling die 5, the two rolling dies 5 rotate synchronously in the same direction, and the two rolling dies 5 are fed radially at the same time , referring to Fig. 3, until the roll forming of the formed spline section a on the workpiece 2 is completed,

The circumferential speed at the maximum addendum circle of the rolling die 5 is 8.5m/min; the radial feed of the rolling die 5 is 0.05mm for each revolution of the workpiece 2;

Step 4, the workpiece 2 is clamped by the front center 1 and the rear center 3 and withdraws in reverse, and the other end of the workpiece 2 has a formed spline segment b. Referring to Figure 4, perform steps 5 to 8;

Step 5, turn workpiece 2 around, re-clamp workpiece 2,

The workpiece 2 is clamped by the front top 1 and the rear top 3, ensuring that the axis of the workpiece 2 is on the same level as the axes of the two rolling dies 5, and the axes of the two rolling dies 5 are parallel and symmetrically distributed on both sides of the workpiece 2. 2. The upper forming spline segment b is close to the rolling die 5;

Step 6, the surface of the formed spline section b on the workpiece 2 is locally heated, specifically:

6.1. The workpiece 2 is fed in the direction of the rolling die 5, and the formed spline section b on the workpiece 2 enters the medium and high frequency induction heater 4, and the medium and high frequency induction heater 4 is arranged at the clamping position of the extrusion rolling die 5 and the workpiece 2 Between, the length of the medium and high frequency induction heater 4 along the axial direction is not less than the length of the spline segment b;

6.2. The medium and high frequency induction heater 4 starts to work, and the surface heating layer depth Δ of the formed spline section b on the workpiece 2 should satisfy the formula Δ=r _Z -r _f +(1.5~2.0)h;

6.3. When the temperature within the depth Δ of the surface heating layer of the formed spline section b on the workpiece reaches the predetermined forming temperature T, the medium and high frequency induction heater 4 stops working, and the forming temperature T is above the temperature of the blue brittle zone of the deformed material. Warm forming temperature below the crystallization temperature, specifically 700°C;

Step 7, the formed spline section b on the workpiece 2 is rolled to form the spline, specifically:

The workpiece 2 is fed in the direction of the rolling die 5, and the formed spline section b on the workpiece 2 enters the working range of the rolling die 5; the two rolling dies 5 rotate synchronously in the same direction, and the two rolling dies 5 are fed radially at the same time , until the roll forming of the formed spline segment b on the workpiece 2 is completed,

The circumferential speed at the maximum addendum circle of the rolling die 5 is 8.5m/min; the radial feed rate of the rolling die 5 is 0.05mm/r for each revolution of the workpiece 2;

Step 8, the workpiece 2 is clamped by the front center 1 and the rear center 3 and withdraws in the reverse direction at the same time, unloading.

Embodiment two:

Only one end of the workpiece 2 formed in this embodiment has a forming spline segment. The material of the workpiece 2 is 42CrMo high-strength steel. The two rolling dies 5 rotate in the same direction synchronously, and the two rolling dies 5 have no radial feed.

Referring to Fig. 1, a method for rolling and forming a spline shaft by medium and high frequency induction heating includes the following steps:

Step 1, clamping workpiece 2,

The workpiece 2 is clamped by the front top 1 and the rear top 3, ensuring that the axis of the workpiece 2 is on the same level as the axes of the two rolling dies 5, and the axes of the two rolling dies 5 are parallel and symmetrically distributed on both sides of the workpiece 2. 2. The upper forming spline section a is close to the rolling die 5;

Step 2, the surface of the formed spline section a on the workpiece 2 is locally heated, specifically:

2.1. The workpiece 2 is fed in the direction of the rolling die 5, and the formed spline section a on the workpiece 2 enters the medium and high frequency induction heater 4. Referring to Figure 2, the medium and high frequency induction heater 4 is extruded between the rolling die 5 and the workpiece 2. Between the clamping positions, the axial length of the medium and high frequency induction heater 4 is not less than the length of the spline section a;

2.2. The medium and high frequency induction heater 4 starts to work, and the surface heating layer depth Δ of the formed spline section a on the workpiece 2 should satisfy the formula Δ=r _Z -r _f +(1.5~2.0)h;

In the formula: r _Z is the radius of the billet before rolling in the spline area of the billet; r _f is the root circle radius of the formed spline; h is the overall height of the formed spline teeth;

2.3. The temperature within the depth Δ of the surface heating layer of the formed spline section a on the workpiece 2 reaches the predetermined forming temperature T, and the medium and high frequency induction heater 4 stops working. The forming temperature T is above the temperature of the blue brittle zone of the deformed material, and the process is fully carried out. Warm forming temperature below the recrystallization temperature, specifically 700°C;

Step 3, forming the spline section a on the workpiece 2 by rolling and forming the spline, specifically:

The workpiece 2 is fed in the direction of the rolling die 5, the formed spline section a on the workpiece 2 enters the working range of the rolling die 5, the two rolling dies 5 rotate synchronously in the same direction, and the two rolling dies 5 have no radial feed, Referring to Fig. 5, until the roll forming of the formed spline section a on the workpiece 2 is completed,

The peripheral speed at the maximum addendum circle of the rolling die 5 is 9m/min;

Step 4, the workpiece 2 is clamped by the front center 1 and the rear center 3 and withdraws in reverse, and only the formed spline section a is on the workpiece 2, referring to Figure 6, unloading.

Claims (1)

1. A method for medium and high frequency induction heating rolling forming spline shaft, characterized in that, comprising the steps: Step 1, clamp the workpiece (2), the workpiece (2) is clamped by the front top (1) and the rear top (3), so that the axis of the workpiece (2) is on the same level as the axes of the two rolling dies (5) On the top, the two rolling dies (5) are parallel in axis and symmetrically distributed on both sides of the workpiece (2), and the forming spline section a on the workpiece (2) is close to the rolling die (5); Step 2, the surface of the formed spline section a on the workpiece (2) is locally heated, specifically: 2.1. The workpiece (2) is fed in the direction of the rolling die (5), and the formed spline section a on the workpiece (2) enters the medium and high frequency induction heater (4), and the medium and high frequency induction heater (4) is arranged in the extrusion Between the rolling die (5) and the clamping position of the workpiece (2), the axial length of the medium and high frequency induction heater (4) is not less than the length of the spline section a; 2.2. The medium and high frequency induction heater (4) starts to work, and the surface heating layer depth Δ of the formed spline section a on the workpiece (2) should satisfy the formula Δ=r _Z -r _f +(1.5~2.0)h; In the formula: r _Z is the radius of the billet before rolling in the spline area of the billet; r _f is the root circle radius of the formed spline; h is the overall height of the formed spline teeth; 2.3. The temperature within the depth Δ of the surface heating layer of the formed spline section a on the workpiece (2) reaches the predetermined forming temperature T, and the medium and high frequency induction heater (4) stops working. The forming temperature T is the temperature in the blue brittle zone of the deformed material Above, warm forming temperature below the temperature for sufficient recrystallization; or hot forming temperature above the temperature for sufficient recrystallization; Step 3, forming the spline section a on the workpiece (2) by rolling and forming the spline, specifically: The workpiece (2) is fed in the direction of the rolling die (5), the formed spline section a on the workpiece 2 enters the working range of the rolling die (5), the two rolling dies (5) rotate synchronously in the same direction, and the two rolling dies (5) The mold (5) performs radial feed or no radial feed at the same time until the roll forming of the formed spline section a on the workpiece (2) is completed, When the rolling die (5) is radially fed, the working surface of the rolling die (5) is completely toothed; when the rolling die (5) has no radial feed, the working surface of the rolling die (5) has The tooth shape part, the incomplete tooth shape part with the tooth height gradually increasing, and the complete tooth shape part, The range of peripheral speed at the maximum addendum circle of the rolling die (5) is 8~10m/min; the radial feed range of the rolling die (5) is 0.05~0.15mm per revolution of the workpiece (2); Step 4, the workpiece (2) is clamped by the front center (1) and the rear center (3) and backed out at the same time, if there is only formed spline section a on the workpiece (2), it will be unloaded directly; if the workpiece (2) If the other end has a formed spline segment b, then perform steps 5 to 8; Step 5, turn the workpiece (2) around, re-clamp the workpiece (2), The workpiece (2) is clamped by the front top (1) and the rear top (3), so that the axis of the workpiece (2) is on the same level as the axes of the two rolling dies (5), and the two rolling dies (5) The axes are parallel and symmetrically distributed on both sides of the workpiece (2), and the formed spline section b on the workpiece (2) is close to the rolling die (5); Step 6, the surface of the formed spline section b on the workpiece (2) is locally heated, specifically: 6.1. The workpiece (2) is fed in the direction of the rolling die (5), and the formed spline section b on the workpiece (2) enters the medium and high frequency induction heater (4), and the medium and high frequency induction heater (4) is arranged in the extrusion Between the rolling die (5) and the clamping position of the workpiece (2), the axial length of the medium and high frequency induction heater (4) is not less than the length of the spline section b; 6.2. The medium and high frequency induction heater (4) starts to work, and the surface heating layer depth Δ of the formed spline section b on the workpiece (2) should satisfy the formula Δ=r _Z -r _f +(1.5~2.0)h; 6.3. When the temperature within the depth Δ of the surface heating layer of the formed spline section b on the workpiece reaches the predetermined forming temperature T, the medium and high frequency induction heater (4) stops working, and the forming temperature T is above the temperature of the blue brittle zone of the deformed material, fully Warm forming temperature below the temperature for recrystallization; or hot forming temperature above the temperature for sufficient recrystallization; Step 7, the formed spline section b on the workpiece (2) is rolled to form the spline, specifically: The workpiece (2) is fed in the direction of the rolling die (5), and the formed spline section b on the workpiece (2) enters the working range of the rolling die (5), and the two rolling dies (5) rotate synchronously in the same direction, and the two The rolling die (5) performs radial feeding or no radial feeding at the same time until the rolling forming of the formed spline section b on the workpiece (2) is completed, When the rolling die (5) is radially fed, the working surface of the rolling die (5) is completely toothed; when the rolling die (5) has no radial feed, the working surface of the rolling die (5) has The tooth shape part, the incomplete tooth shape part with the tooth height gradually increasing, and the complete tooth shape part, The range of peripheral speed at the maximum addendum circle of the rolling die (5) is 8~10m/min; the radial feed range of the rolling die (5) is 0.05~0.15mm per revolution of the workpiece (2); Step 8, the workpiece (2) is clamped by the front center (1) and the rear center (3) and withdraws in reverse at the same time, unloading.