Electromagnetic induction heating of steel pipe apparatus and method of heating steel pipe

Abstract

The application discloses a kind of electromagnetic induction heating steel pipe device and heating steel pipe method.The device of the application includes roller bed (1) and several electromagnetic heating components (2), and roller bed is arranged on steel pipe production line;Several electromagnetic heating components are arranged in roller bed with interval;Each electromagnetic heating component, electromagnetic heating component includes transverse rail (21), transverse platform (22) and at least two electromagnetic coil units.The method of the application includes: according to the specification of steel pipe (5), the electromagnetic coil unit of electromagnetic heating component matched with the specification of steel pipe is aligned with roller;According to the moving speed of steel pipe and the temperature amplitude that each position needs heating to improve in longitudinal full length, the time node of each position of steel pipe longitudinal full length when passing each electromagnetic coil unit and the heating power required by the time node are determined.The heating steel pipe device and heating steel pipe method of the application can adapt to multi-specification steel pipe production line, and improve the longitudinal temperature consistency of heating steel pipe.

Description

Technical Field

[0001] This invention relates to a heating technology in the production process of seamless steel pipes, and more particularly to an electromagnetic induction heating device and method for heating steel pipes. Background Technology

[0002] Currently, electromagnetic induction heating devices are widely used on seamless steel pipe production lines to heat the steel pipes during the rolling process, ensuring that the pipe temperature meets the requirements of the rolling process. An electromagnetic induction heating device typically consists of multiple electromagnetic coil units arranged in a series. Each electromagnetic coil unit has a central channel around which an electromagnetic coil is positioned and connected to a high-power power source. When heating is required, the steel pipe is passed through the channel of the electromagnetic coil units. The high-power power source is then activated on the electromagnetic coils, generating high-power electromagnetic waves that cause electromagnetic oscillations in the steel pipe within the channel, thus generating heat and achieving the desired heating effect.

[0003] Existing electromagnetic induction heating devices only have one diameter specification for the electromagnetic coil unit's channel, limiting the range of steel pipe sizes they can heat. Steel pipes exceeding a certain size range cannot be heated. Therefore, existing electromagnetic induction heating devices have poor adaptability to multi-specification steel pipe production lines, thus restricting their capabilities. Furthermore, when heating hollow tube billets, the temperature drop at the beginning and end of the billet varies along its length, resulting in longitudinal temperature differences. This is detrimental to subsequent rolling deformation and can easily lead to uneven wall thickness and other quality problems. Therefore, it is necessary to adjust the longitudinal temperature of the steel pipe to achieve temperature consistency throughout its entire length.

[0004] The following are relevant patent documents retrieved in this field:

[0005] Chinese patent (CN114130934A) discloses a heating plate manufactured by high-temperature forging and a high-temperature forging process, including a forging press, transmission box, worktable, motor, gears, transmission mechanism, screw, and transmission block. It solves the problem that most existing forging devices on the market lack a rapid ejection function, achieving the effect of rapidly ejecting the heating plate. However, this method cannot achieve continuous heating and temperature replenishment for multi-specification steel pipes.

[0006] Chinese patent (CN114058805A) discloses an induction quenching and tempering equipment for wheel bodies, including a feeding device, a quenching device, a tempering device, a discharge buffer device, a loading device, and a unloading device. This equipment offers a simpler, more rational, and more aesthetically pleasing design for wheel bodies, with a faster cycle time and higher consistency of the hardened layer. It can also be used for large-scale, continuous production of wheel body workpieces of different sizes. However, this method uses a bed structure and manual loading, making it unsuitable for the production of large-tonnage seamless steel pipes, and even less suitable for reducing the longitudinal temperature difference of the steel pipe through heat compensation. Summary of the Invention

[0007] The purpose of this invention is to provide an electromagnetic induction heating steel pipe device and a steel pipe heating method, which can be adapted to multi-specification steel pipe production lines, and can use all or part of the electromagnetic coil units to heat the steel pipe, and also improves the longitudinal temperature uniformity of the heated steel pipe.

[0008] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution:

[0009] An electromagnetic induction heating steel pipe device includes a roller conveyor and several electromagnetic heating components. The roller conveyor is installed on a steel pipe production line. The several electromagnetic heating components are spaced apart in the roller conveyor. For each group of electromagnetic heating components, the electromagnetic heating component includes a transverse track, a transverse platform, and at least two electromagnetic coil units. The transverse track is located at the gap between the rollers of the roller conveyor, and the guiding direction of the transverse track is perpendicular to the conveying direction of the roller conveyor. A guide wheel driven by a motor is installed on the lower part of the transverse platform, and the transverse platform is mounted on the transverse track through the guide wheel, and the guide wheel of the transverse platform cooperates with the wheel rail of the transverse track. The electromagnetic coil units are placed on the platform surface, and the central axis of the channel of the electromagnetic coil unit is parallel to the conveying direction of the roller conveyor. The specifications of each electromagnetic coil unit are different.

[0010] Furthermore, the electromagnetic heating assembly also includes a heat insulation cover, which is mounted on a transverse platform.

[0011] Furthermore, the electromagnetic induction heating steel pipe device also includes an upstream temperature measuring instrument and a downstream temperature measuring instrument, wherein the upstream temperature measuring instrument is installed on the upstream side of the roller conveyor and the downstream temperature measuring instrument is installed on the downstream side of the roller conveyor.

[0012] Furthermore, the electromagnetic heating assembly includes two electromagnetic coil units, namely a small-sized electromagnetic coil unit and a large-sized electromagnetic coil unit.

[0013] Furthermore, the electromagnetic induction heating steel pipe device includes 7 sets of electromagnetic heating components.

[0014] A method for electromagnetic induction heating of steel pipes, the method being based on the aforementioned electromagnetic induction heating steel pipe apparatus, the method comprising:

[0015] S1, Determine the specifications of the steel pipe that needs to be heated;

[0016] S2, according to the steel pipe specifications, select the electromagnetic coil unit of the electromagnetic heating assembly that matches the steel pipe specifications and align it with the roller conveyor;

[0017] S3 controls the roller conveyor to pass the steel pipe through the aligned electromagnetic coil units in the roller conveyor at a uniform speed.

[0018] S4. During the movement of the steel pipe, the temperature of the steel pipe is measured along its entire length by an upstream temperature measuring instrument to obtain the longitudinal temperature data of the steel pipe. The longitudinal temperature data of the steel pipe is compared with the target heating temperature to determine the temperature increase required at each position along the longitudinal length of the steel pipe.

[0019] S5. Based on the moving speed of the steel pipe and the temperature increase required at each position along the longitudinal length, determine the time node when the steel pipe passes through each electromagnetic coil unit and the heating power required at that time node.

[0020] S6, each electromagnetic coil unit heats the steel pipe to a uniform longitudinal temperature by adjusting its power;

[0021] S7, the heated steel pipe is subjected to full-length temperature measurement again by the downstream temperature measuring instrument to obtain the longitudinal full-length temperature data of the heated steel pipe.

[0022] S8 compares the longitudinal temperature data of the heated steel pipe with the target heating temperature and calculates the temperature difference between the two. The temperature difference is then fed back to the production process control computer. When heating subsequent steel pipes, the production process control computer adjusts the heating power to improve the longitudinal temperature consistency of the subsequently heated steel pipes.

[0023] The electromagnetic induction heating steel pipe device of the present invention includes several sets of electromagnetic heating components. A transverse platform within each electromagnetic heating component is mounted on a transverse track via guide wheels. Electromagnetic coil units of different specifications are arranged on the transverse platform. When heating steel pipes using this device, different specifications of electromagnetic coil units can be selected from the electromagnetic heating components to heat the steel pipe according to its size. By controlling the transverse platform to move laterally relative to the roller conveyor along the transverse track, the selection and switching of electromagnetic coil units of different specifications can be achieved, thereby expanding the range of steel pipe specifications that the electromagnetic induction heating steel pipe device can heat. Furthermore, all or some of the electromagnetic coil units can be selected to participate in heating the steel pipe based on the total power required. In the steel pipe heating method of the present invention, electromagnetic coil units matching the specifications of the steel pipe are selected to heat the steel pipe, thereby expanding the range of steel pipe specifications that the electromagnetic induction heating steel pipe device can heat.

[0024] In the heating steel pipe method of the present invention, the time node when each position of the steel pipe passes through each electromagnetic coil unit and the heating power required at each time node are determined according to the moving speed of the steel pipe and the temperature increase required at each position along the longitudinal length. Then, each electromagnetic coil unit heats the steel pipe to a uniform longitudinal temperature by adjusting the power.

[0025] Compared with the prior art, the electromagnetic induction heating steel pipe device and heating method of the present invention have the following advantages: They expand the range of steel pipe specifications that the electromagnetic induction heating steel pipe device can heat, fully utilize the heating capacity, and the control selection and switching process is simple and convenient, greatly improving the adaptability to multi-specification steel pipe production lines; furthermore, by selecting all or part of the electromagnetic coil units of the electromagnetic heating components to participate in heating the steel pipe, precise heating of the steel pipe is achieved using appropriate heating power; the electromagnetic induction heating steel pipe method of the present invention also improves the longitudinal temperature consistency of the steel pipe, reduces the error with the target heating temperature, and thus helps to improve the level of steel pipe rolling process. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the electromagnetic induction heating steel pipe device of the present invention heating a steel pipe, wherein the steel pipe is a large-size steel pipe, and the heating steel pipe device uses all large-size electromagnetic coil units to heat the steel pipe.

[0027] Figure 2 for Figure 1 Enlarged view of the area within the dashed box;

[0028] Figure 3 This is a schematic diagram of the electromagnetic induction heating steel pipe device of the present invention heating a steel pipe, wherein the steel pipe is a small-sized steel pipe, and the heating steel pipe device uses a portion of small-sized electromagnetic coil units to heat the steel pipe;

[0029] Figure 4 This is a computer program flowchart of the electromagnetic induction heating steel pipe method of the present invention.

[0030] In the diagram: 1-roller conveyor, 2-electromagnetic heating assembly, 21-transverse track, 22-transverse platform, 25-insulation cover, 23-small electromagnetic coil unit, 24-large electromagnetic coil unit, 3-upstream temperature measuring instrument, 4-downstream temperature measuring instrument, 5-steel pipe. Detailed Implementation

[0031] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:

[0032] See Figures 1 to 3 This embodiment provides an electromagnetic induction heating steel pipe device, which heats the steel pipe during the rolling process so that the temperature of the steel pipe can meet the requirements of the rolling process.

[0033] See Figure 1 The electromagnetic induction heating steel pipe device of this embodiment includes a roller conveyor 1, a temperature measuring instrument, and an electromagnetic heating component 2.

[0034] The roller conveyor 1 is installed on the seamless steel pipe production line. Specifically, after the hollow tube blank (i.e., steel pipe) is produced by the multi-strand continuous casting machine, it is transported to the roller conveyor by a distribution conveyor trolley, and then transported to the continuous rolling mill. That is, the roller conveyor 1 is located between the distribution conveyor trolley and the continuous rolling mill, and is installed on a specially equipped frame platform. In this embodiment, the operation of the roller conveyor 1 is controlled by the production process control computer at the work site, which can control the roller conveyor 1 to transport the steel pipe 5.

[0035] Those skilled in the art will understand that roller conveyors are common equipment in steel plants. They consist of numerous horizontally arranged cylindrical rollers mounted on the ground or on the equipment frame via supports. The rollers are driven by motors. The function of roller conveyor 1 is to transport solid steel materials, especially high-temperature steel materials, on the steel production line.

[0036] The thermometers are in two sets: an upstream thermometer 3 and a downstream thermometer 4. The upstream thermometer 3 is installed on the upstream side of the roller conveyor 1 and is used to measure the initial temperature of the steel pipe 5 as it enters the electromagnetic induction heating device. The downstream thermometer 4 is installed on the downstream side of the roller conveyor 1 and is used to measure the temperature of the steel pipe 5 after heating, obtaining its final temperature.

[0037] In this embodiment, both the upstream temperature measuring instrument 3 and the downstream temperature measuring instrument 4 are connected to the production process control computer via signals. The production process control computer can obtain the initial temperature and the temperature after heating of the steel pipe through the upstream temperature measuring instrument 3 and the downstream temperature measuring instrument 4, respectively.

[0038] It should be noted that the upstream and downstream sides mentioned here refer to the production line. Specifically, the upstream side is the side opposite to the production line, while the downstream side is the side in the same direction as the production line.

[0039] The number of electromagnetic heating components 2 is 7 sets, and these 7 sets of electromagnetic heating components 2 are arranged in the roller conveyor 1 at intervals between the rollers. The phrase "arranged at intervals between the rollers" means that each set of electromagnetic heating components 2 is located in the gap between the rollers in the roller conveyor 1, and all 7 sets of electromagnetic heating components 2 are evenly distributed in the roller conveyor 1.

[0040] It should be noted that in other embodiments of the electromagnetic induction heating steel pipe device, the specific number of electromagnetic heating components 2 can be set as needed. In general, the number of electromagnetic heating components 2 included in the heating steel pipe device can be several groups.

[0041] See Figure 2 The following is a description of the single electromagnetic heating component 2.

[0042] For each set of electromagnetic heating components 2, a set of electromagnetic heating components 2 includes a transverse track 21, a transverse platform 22, an electromagnetic coil unit and a heat preservation cover 25.

[0043] The transverse track 21 is a double track. The transverse track 21 is set at the gap between the rollers of the roller conveyor 1 and is installed on the frame platform where the roller conveyor 1 is located. The guiding direction of the transverse track 21 is perpendicular to the conveying direction of the roller conveyor 1, or it can be said that the guiding direction of the transverse track 21 is perpendicular to the production line direction.

[0044] The lower part of the transverse platform 22 is equipped with four guide wheels (not shown in the figure) driven by motors. These four guide wheels match the transverse track 21, and the transverse platform 22 is mounted on the transverse track 21 via the four guide wheels. The four guide wheels of the transverse platform 22 engage with the wheel rails of the transverse track 21. The motor driving the four guide wheels is installed at the lower part of the transverse platform 22. This motor is called a transverse motor and is controlled by the production process control computer. The four guide wheels are all driven to rotate by this transverse motor. That is to say, the rotation of the four guide wheels is controlled by the production process control computer. In this way, the production process control computer can control the transverse platform 22 to move laterally relative to the roller conveyor 1 along the transverse track 21.

[0045] It should be noted that in other embodiments of the electromagnetic induction heating steel pipe device, the number of guide wheels provided at the lower part of the transverse platform 22 can be determined according to actual needs.

[0046] Those skilled in the art will understand that "the guide wheel is driven by a motor" means that the axle of the guide wheel is connected to the drive shaft of the motor through a transmission mechanism, and the motor can then drive the guide wheel to rotate through the transmission mechanism. This is conventional practice and common knowledge that is known to those skilled in the art and will not be misunderstood. The transmission mechanism mentioned here can be a gear transmission mechanism, sprocket transmission mechanism, or belt pulley transmission mechanism, etc., which are existing technologies.

[0047] Both the electromagnetic coil unit and the heat insulation cover 25 are installed on the platform of the transverse platform 22.

[0048] The electromagnetic heating assembly 2 includes two electromagnetic coil units: a small electromagnetic coil unit 23 and a large electromagnetic coil unit 24. Both the small electromagnetic coil unit 23 and the large electromagnetic coil unit 24 are mounted on the platform of the transverse platform 22. The central axis of the channels of the two electromagnetic coil units is parallel to the conveying direction of the roller conveyor 1, and the height of the channels of the electromagnetic coil units matches the height of the roller conveyor 1.

[0049] In this embodiment, the electromagnetic coil units (small-sized electromagnetic coil unit 23 and large-sized electromagnetic coil unit 24) included in the electromagnetic heating assembly 2 are controlled by the production process control computer, which can control the electromagnetic coil units to heat the steel pipe.

[0050] It should be noted that in other embodiments, more electromagnetic coil units can be set on the transverse platform 22 according to different needs, but at least two are required, and the specifications of the electromagnetic coil units are different, in order to expand the range of steel pipe specifications that the electromagnetic induction heating steel pipe device can heat.

[0051] It should be noted that the specifications of the electromagnetic coil unit mentioned in this article are based on the channel of the electromagnetic coil unit, specifically, the diameter specification of the channel.

[0052] Those skilled in the art will understand that the electromagnetic coil unit is a prior art component, which has a channel in its center and an electromagnetic coil is arranged around the channel. The electromagnetic coil is connected to a high-power power supply. When the steel pipe enters the channel of the electromagnetic coil unit, the electromagnetic coil is connected to the high-power power supply. The high-power electromagnetic waves generated by the electromagnetic coil can generate electromagnetic excitation on the steel pipe in the channel, thereby causing the steel pipe to generate heat and achieve the purpose of heating the steel pipe.

[0053] The heat insulation cover 25 is shaped like an inverted "U" and resembles an arch. It is installed on the platform of the transverse platform 22 and is located between the small electromagnetic coil unit 23 and the large electromagnetic coil unit 24. Its direction of penetration is consistent with the conveying direction of the roller conveyor 1. Its function is to insulate the steel pipes that pass through and prevent the heat from dissipating.

[0054] It should be noted that there are no particular restrictions on the specific positions of the electromagnetic coil unit and the heat insulation cover 25 on the transverse platform 22. For example, it is also possible to install the two electromagnetic coil units together and install the heat insulation cover 25 on the side of the transverse platform 22. This does not substantially affect the innovative concept of the heating steel pipe device in this embodiment.

[0055] When heating the steel pipe 5 using the electromagnetic induction heating steel pipe device of this embodiment, the large-size electromagnetic coil unit 24 or the small-size electromagnetic coil unit 23 in the electromagnetic heating assembly 2 can be selected to heat the steel pipe according to the size of the steel pipe. In addition, all or part of the electromagnetic coil units of the electromagnetic heating assembly can be selected to participate in heating the steel pipe according to the total power required to heat the steel pipe.

[0056] See Figure 1 ,Should Figure 1 The diagram illustrates the use of all electromagnetic heating components 2 to heat a large-diameter steel pipe. First, the production process control computer obtains the specifications of the steel pipe 5 to be heated via the work area network system. It confirms that the steel pipe 5 is a large-diameter pipe and that all electromagnetic heating components 2 are required to heat it. The production process control computer then controls the transverse platforms 22 of all electromagnetic heating components 2 in the roller conveyor 1 to move laterally relative to the roller conveyor 1 along the transverse track 21, aligning the large-diameter electromagnetic coil units 24 with the roller conveyor 1 (i.e., aligning the channels of the electromagnetic coil units with the roller conveyor 1). Once all the large-diameter electromagnetic coil units 24 of the electromagnetic heating components 2 are aligned with the roller conveyor 1, the production process control computer connects the large-diameter electromagnetic coil units 24 aligned with the roller conveyor 1 to a high-power power supply and controls the roller conveyor 1 to pass the steel pipe 5 at a uniform speed through the channels of the aligned large-diameter electromagnetic coil units 24. The large-diameter electromagnetic coil units 24 then electromagnetically heat the passing steel pipe 5.

[0057] See Figure 3 ,Should Figure 3The image shows the use of a partial electromagnetic heating assembly 2 to heat a small-diameter steel pipe. First, the production process control computer obtains the specification information of the steel pipe to be heated through the work area network system. It confirms that the steel pipe is a small-sized pipe and that only a portion of the electromagnetic heating components 2 are needed to heat it. The production process control computer then controls the transverse platform 22 of a portion of the electromagnetic heating components 2 involved in the heating in the roller conveyor 1 to move along the transverse track 21 to the position where the small-sized electromagnetic coil unit 23 is aligned with the roller conveyor 1. Meanwhile, the transverse platform 22 of the other electromagnetic heating components 2 not involved in the heating moves along the transverse track 21 to the position where the heat preservation cover 25 is aligned with the roller conveyor 1. After all the transverse platforms 22 of the electromagnetic heating components 2 have completed their alignment, the production process control computer controls the small-sized electromagnetic coil unit 23 aligned with the roller conveyor 1 to connect to a high-power power supply and controls the roller conveyor 1 to pass the steel pipe 5 at a uniform speed through the channels of the aligned small-sized electromagnetic coil units 23 and the heat preservation cover 25 in the roller conveyor 1. The small-sized electromagnetic coil unit 23 then electromagnetically heats the passing steel pipe 5, while the heat preservation cover 25 serves to keep it warm.

[0058] It should be noted that the total power required to heat the steel pipe is determined based on the difference between the initial temperature of the steel pipe measured by the upstream temperature measuring instrument 3 and the target heating temperature. When the difference is large, a larger heating power is used to heat the steel pipe, that is, more electromagnetic coil units of the electromagnetic heating component 2 are used to participate in heating the steel pipe. Conversely, when the difference is small, a smaller heating power is used to heat the steel pipe, that is, fewer electromagnetic coil units of the electromagnetic heating component 2 are used to participate in heating the steel pipe. The target heating temperature mentioned here refers to the steel pipe temperature that meets the requirements of the rolling production process.

[0059] The electromagnetic induction heating steel pipe device of this embodiment includes 7 sets of electromagnetic heating components 2. The transverse platform 22 of the electromagnetic heating component 2 is mounted on the transverse track 21 via guide wheels. The transverse platform 22 is equipped with two electromagnetic coil units of different specifications: a small-sized electromagnetic coil unit 23 and a large-sized electromagnetic coil unit 24. When heating steel pipes using the heating steel pipe device of this embodiment, the large-sized electromagnetic coil unit 24 or the small-sized electromagnetic coil unit 23 in the electromagnetic heating component 2 can be selected to heat the steel pipe according to its size. As long as the transverse platform 22 is controlled to move laterally relative to the roller conveyor 1 along the transverse track 21, the selection and switching between the large-sized electromagnetic coil unit 24 and the small-sized electromagnetic coil unit 23 can be realized. This not only expands the range of steel pipe specifications that the electromagnetic induction heating steel pipe device can heat and fully utilizes its capabilities, but also makes the selection and switching process simple and convenient, greatly improving the adaptability to multi-specification steel pipe production lines. Furthermore, when heating the steel pipe using the heating steel pipe device of this embodiment, the electromagnetic coil units of all or part of the electromagnetic heating component 2 can be selected to participate in heating the steel pipe according to the total power required for heating the steel pipe, thereby realizing the precise heating of the steel pipe using appropriate heating power.

[0060] See Figure 4 This embodiment also provides a method for heating steel pipes by electromagnetic induction. This method is based on the electromagnetic induction heating steel pipe device described above, in which the electromagnetic induction heating steel pipe device is used to heat the steel pipe.

[0061] The electromagnetic induction heating method for steel pipes in this embodiment includes steps S1 to S8.

[0062] S1, determine the specifications of the steel pipe that needs to be heated.

[0063] S2, according to the specifications of steel pipe 5, control the transverse platform 22 of electromagnetic heating component 2 to move laterally relative to roller conveyor 1 along transverse track 21, and select the electromagnetic coil unit of electromagnetic heating component 2 that matches the specifications of steel pipe 5 to align with roller conveyor 1.

[0064] S3, control the roller conveyor 1 to pass the steel pipe 5 through the channels of the aligned electromagnetic coil units in the roller conveyor 1 at a uniform speed.

[0065] S4. During the movement of the steel pipe, the upstream temperature measuring instrument 3 measures the temperature of the steel pipe along its entire length to obtain the longitudinal temperature data of the steel pipe. Then, the longitudinal temperature data of the steel pipe is compared with the target heating temperature to determine the temperature increase required at each position along the longitudinal length of the steel pipe.

[0066] S5. Based on the moving speed of the steel pipe and the temperature increase required at each position along the longitudinal length, determine the time node when each position along the longitudinal length of the steel pipe passes through each electromagnetic coil unit and the heating power required at that time node.

[0067] S6, each electromagnetic coil unit heats the steel pipe to a uniform longitudinal temperature by adjusting its power.

[0068] S7, the downstream temperature measuring instrument 4 performs a full-length temperature measurement on the heated steel pipe again to obtain the longitudinal full-length temperature data of the heated steel pipe.

[0069] S8 compares the longitudinal temperature data of the heated steel pipe with the target heating temperature again and calculates the temperature difference between the two. The temperature difference is then fed back to the production process control computer. When heating subsequent steel pipes, the production process control computer controls the electromagnetic induction heating steel pipe device to adjust the heating power, thereby improving the longitudinal temperature consistency of subsequent heated steel pipes and reducing the deviation from the target heating temperature.

[0070] In the steel pipe heating method of this embodiment, an electromagnetic coil unit matching the specifications of the steel pipe 5 is selected to heat the steel pipe 5, thereby expanding the range of steel pipe specifications that the electromagnetic induction heating steel pipe device can heat, fully utilizing its capabilities, and greatly improving the adaptability to multi-specification steel pipe production lines. In addition, based on the steel pipe's moving speed and the required temperature increase at each position along the longitudinal length, the time nodes when each position along the longitudinal length of the steel pipe passes through each electromagnetic coil unit and the heating power required at that time node are determined. Then, each electromagnetic coil unit heats the steel pipe to a uniform longitudinal temperature by adjusting its power, thereby improving the longitudinal temperature uniformity of the steel pipe, reducing the error with the target heating temperature, and thus helping to improve the steel pipe rolling process level.

[0071] It should be noted that the steel pipe heating method of this embodiment is set in the production process control computer in the form of a program. During the heating process of the steel pipe, the steel pipe heating method of this embodiment is implemented by the production process control computer executing the program. Figure 4 The diagram shown is a computer program flowchart for implementing the method of heating steel pipes.

[0072] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An electromagnetic induction heating device for steel pipes, characterized in that: It includes a roller conveyor (1) and several sets of electromagnetic heating components (2); The roller conveyor (1) is installed on the steel pipe production line; The plurality of electromagnetic heating components (2) are arranged at intervals between the rollers in the roller table (1), and each electromagnetic heating component (2) is arranged at the gap between the rollers in the roller table (1). For each set of electromagnetic heating components (2), the electromagnetic heating component (2) includes a transverse track (21), a transverse platform (22), and at least two electromagnetic coil units; the transverse track (21) is set at the gap between the rollers of the roller conveyor (1), and the guiding direction of the transverse track (21) is perpendicular to the conveying direction of the roller conveyor (1); the lower part of the transverse platform (22) is equipped with a guide wheel driven by a motor, and the transverse platform (22) is placed on the transverse track (21) through the guide wheel, and the guide wheel of the transverse platform (22) is in wheel-rail cooperation with the transverse track (21); the electromagnetic coil units are placed on the platform of the transverse platform (22), and the central axis of the channel of the electromagnetic coil unit is parallel to the conveying direction of the roller conveyor (1), and the specifications of each electromagnetic coil unit are different; According to the specifications of the steel pipe (5), the electromagnetic coil unit of the electromagnetic heating assembly (2) that matches the specifications of the steel pipe (5) is aligned with the roller conveyor (1).

2. The electromagnetic induction heating steel pipe device according to claim 1, characterized in that: The electromagnetic heating assembly (2) also includes a heat insulation cover (25), which is mounted on a transverse platform (22).

3. The electromagnetic induction heating steel pipe device according to claim 1, characterized in that: The electromagnetic induction heating steel pipe device also includes an upstream temperature measuring instrument (3) and a downstream temperature measuring instrument (4). The upstream temperature measuring instrument (3) is installed on the upstream side of the roller conveyor (1), and the downstream temperature measuring instrument (4) is installed on the downstream side of the roller conveyor (1).

4. The electromagnetic induction heating steel pipe device according to claim 1, characterized in that: The electromagnetic heating assembly (2) includes two electromagnetic coil units, namely a small electromagnetic coil unit (23) and a large electromagnetic coil unit (24).

5. The electromagnetic induction heating steel pipe device according to claim 1, characterized in that: The electromagnetic induction heating steel pipe device includes 7 sets of electromagnetic heating components (2).

6. A method for electromagnetic induction heating of a steel pipe, said method being based on the electromagnetic induction heating steel pipe apparatus of claim 1, characterized in that: The electromagnetic induction heating steel pipe device also includes an upstream temperature measuring instrument (3) and a downstream temperature measuring instrument (4). The upstream temperature measuring instrument (3) is installed on the upstream side of the roller conveyor (1), and the downstream temperature measuring instrument (4) is installed on the downstream side of the roller conveyor (1). The electromagnetic induction heating method for steel pipes includes: S1, Determine the specifications of the steel pipe that needs to be heated; S2, according to the specifications of the steel pipe (5), select the electromagnetic coil unit of the electromagnetic heating assembly (2) that matches the specifications of the steel pipe (5) and align it with the roller conveyor (1); S3, control the roller conveyor (1) to pass the steel pipe (5) through the aligned electromagnetic coil units in the roller conveyor (1) at a uniform speed; S4. During the movement of the steel pipe, the temperature of the steel pipe is measured along its entire length by the upstream temperature measuring instrument (3) to obtain the longitudinal temperature data of the steel pipe. The longitudinal temperature data of the steel pipe is compared with the target heating temperature to determine the temperature range that needs to be increased at each position along the longitudinal length of the steel pipe. S5. Based on the moving speed of the steel pipe and the temperature increase required at each position along the longitudinal length, determine the time node when the steel pipe passes through each electromagnetic coil unit and the heating power required at that time node. S6, each electromagnetic coil unit heats the steel pipe to a uniform longitudinal temperature by adjusting its power; S7, the heated steel pipe is subjected to full-length temperature measurement again by the downstream temperature measuring instrument (4) to obtain the longitudinal full-length temperature data of the heated steel pipe. S8 compares the longitudinal temperature data of the heated steel pipe with the target heating temperature and calculates the temperature difference between the two. The temperature difference is then fed back to the production process control computer. When heating subsequent steel pipes, the production process control computer adjusts the heating power to improve the longitudinal temperature consistency of the subsequently heated steel pipes.

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