Equipment and method for improving induction heating speed and heating uniformity of pipe

Abstract

The invention relates to equipment and a method for improving the induction heating speed and the heating uniformity of a pipe, belongs to the technical field of induction heat treatment quenching equipment, and solves the problem that the equipment cost and the energy cost cannot be reduced while the heating speed and the heating uniformity of the existing induction heating equipment are improved. The equipment comprises a transmission system, a preheating assembly, an induction heating assembly and a cooling system, the transmission system is used for conveying the pipe, the preheating assembly is used for preheating the pipe, the induction heating assembly is used for heating the pipe to reach the complete austenitizing temperature, and the cooling system is used for cooling the heated pipe; both the preheating assembly and the induction heating assembly adopt longitudinal magnetism to heat the pipe; the preheating assembly, the induction heating assembly and the cooling system are sequentially arranged in the advancing direction of the pipe.

Description

Technical Field

[0001] The invention relates to the technical field of induction heat treatment quenching equipment, and in particular to an equipment and method for improving the induction heating speed and heating uniformity of a pipe. Background Art

[0002] The principle of induction heating is mainly based on three basic principles: electromagnetic induction, skin effect and heat conduction. When an alternating current passes through a conductor, an alternating magnetic field is formed around the conductor. According to Faraday's law of electromagnetic induction, an induced electromotive force is generated inside the conductor, which in turn generates eddy currents. These eddy currents circulate inside the conductor. Due to the resistance of the conductor, the eddy currents generate heat when passing through the conductor. This is the Joule heating effect. Induction heating uses the heat energy generated by this eddy current to heat the metal blank.

[0003] The principles of induction heating mainly include electromagnetic induction, Joule heating effect and hysteresis thermal effect. When an alternating current passes through the coil, an alternating magnetic field is established in the space around the coil, and an induced electromotive force is generated in the metal workpiece in the alternating magnetic field, thereby generating eddy currents; induction heating is to use the heat energy generated by eddy currents to heat metal blanks. The Joule effect can be expressed by the following formula: Q = I2Rt, where Q is heat, I is current, R is resistance, and t is time; for ferromagnetic metal materials, a small part of the induction heating comes from hysteresis loss, and the hysteresis thermal effect mainly occurs when the ferromagnetic material is below the Curie point temperature. The magnetic domain structure formed by spontaneous magnetization inside the material is continuously magnetized and demagnetized in the medium and high frequency alternating magnetic field. When the magnetic domain changes its direction, it rubs against the surrounding magnetic domains to generate heat. The superposition of electromagnetic induction, Joule heating effect and hysteresis thermal effect is the reason for the fast speed of induction heating. However, when the temperature of the workpiece exceeds the Curie point, the ferromagnetic workpiece turns into a paramagnetic material, and the hysteresis thermal effect disappears. At this time, the temperature rises mainly by the Joule heating effect. This is because the eddy currents generated during the induction heating process circulate inside the metal. Due to the resistance of the metal, the eddy currents generate heat when passing through the metal. The generation of this heat has nothing to do with whether the material is magnetic, but only with the resistance of the material and the size of the eddy currents.

[0004] The Curie point of steel is around 770℃. Above this temperature, the efficiency of induction heating of steel drops significantly, and the steel has not yet reached full austenitization. Increasing the heating time can indeed make the temperature of the steel reach the full austenitization temperature. Due to the skin effect, when the temperature of the core of the steel reaches the full austenitization temperature, the surface temperature will far exceed the full austenitization temperature, resulting in a very coarse surface structure of the steel and poor overall uniformity. Therefore, the steel that is quenched by induction heating in China is basically 5mm thick or less. When using induction heating equipment for steel thicker than 5mm, it will only be used for tempering, which seriously hinders the application of induction heating in the field of steel heat treatment.

[0005] For the induction heating of the plate, the existing technology uses a combination of longitudinal and transverse magnetic fields, and the entire induction heating is performed in an atmosphere furnace to improve the heating uniformity and speed of the plate. On the one hand, the energy utilization efficiency of transverse magnetic heating is low, and on the other hand, the entire induction heating is performed in an atmosphere furnace, which increases the size of the equipment, has high equipment costs, and occupies a large area.

[0006] For pipes, if the above-mentioned induction heating equipment is used, the equipment cost and energy cost will be high. Therefore, there is an urgent need for an induction heating equipment for pipes that can improve the heating speed and heating uniformity, has high energy utilization and low equipment cost. Summary of the invention

[0007] In view of the above analysis, the present invention aims to provide a device and method for improving the induction heating speed and heating uniformity of pipes, so as to solve the problem that the existing induction heating equipment cannot reduce the equipment cost and energy cost while improving the heating speed and heating uniformity.

[0008] The purpose of the present invention is mainly achieved through the following technical solutions:

[0009] In a first aspect, the present invention provides an apparatus for improving the induction heating speed and heating uniformity of a pipe, comprising a transmission system, a preheating component, an induction heating component and a cooling system;

[0010] The transmission system is used to transport the pipe, the preheating assembly is used to preheat the pipe, the induction heating assembly is used to heat the pipe to reach a complete austenitizing temperature, and the cooling system is used to cool the heated pipe;

[0011] The preheating assembly and the induction heating assembly both use longitudinal magnetism to heat the pipe;

[0012] Along the traveling direction of the pipe, the preheating component, the induction heating component and the cooling system are arranged in sequence.

[0013] Optionally, the preheating assembly includes a first preheating transformer, a first preheating inductor and a first preheating induction coil connected in sequence; and a second preheating transformer, a second preheating inductor and a second preheating induction coil connected in sequence;

[0014] The first preheating transformer is used to provide a stable voltage and current to the first preheating inductor; the first preheating induction coil is used to provide a magnetic field to heat the pipe; the first preheating inductor is used to provide a current of a specific frequency to the first preheating induction coil, thereby generating a magnetic field of a specific frequency.

[0015] Optionally, the induction heating assembly comprises a transformer, an inductor and an induction coil connected in sequence;

[0016] The induction coil includes a first induction coil and a second induction coil, and both the first induction coil and the second induction coil are connected to the inductor.

[0017] Optionally, a cooling tower is further included, and the cooling medium in the cooling tower is used to cool the induction heating component and supply the cooling system.

[0018] Optionally, the induction coils in the preheating assembly and the induction heating assembly are both wrapped with insulating high-temperature resistant materials.

[0019] Optionally, the cooling tower adopts a double water tank design, the cooling medium in one water tank is used to cool the induction heating component, and the cooling medium in the other water tank is used to supply cooling medium to the cooling system.

[0020] Optionally, a groove is provided in the middle of the transmission roller of the transmission system, and the pipe is placed in the groove.

[0021] Optionally, the inlet end of the transmission system is higher than the outlet end.

[0022] Optionally, the cooling system comprises a nozzle for spraying onto the surface of the pipe and an inner nozzle for spraying onto the inner wall of the pipe.

[0023] In a second aspect, the present invention further provides a method for improving the induction heating speed and heating uniformity of a pipe, using the above-mentioned device, comprising the following steps:

[0024] Step 1: Check whether the water circuit and circuit are normal;

[0025] Step 2: The pipe is placed on the transmission system, and the transformer switch of the preheating component and / or the induction heating component is turned on; the transmission system is started, and the pipe passes through the preheating induction coil of the preheating component, the induction coil of the induction heating component and the cooling system in sequence.

[0026] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0027] (1) The present invention is provided with a plurality of coils along the traveling direction of the pipe, and the plurality of coils are all longitudinal magnetic induction heating, and the plurality of coils are provided with different heating rates and frequencies. The pipe is first preheated by low power and ultrasonic frequency, and then the pipe is induction heated by medium or high power and medium frequency. By combining different powers and different frequencies, the heating rate and heating uniformity of the pipe are improved (see the data in Table 1), so that the pipe can reach the complete austenitization temperature or even higher when passing through the induction coil, and the uniformity of the structure is good.

[0028] (2) The equipment of the present invention includes a preheating component and an induction heating component. Preheating is performed before induction heating of the pipe, which is beneficial to increasing the heating rate of the pipe and reducing the induction heating time of the pipe.

[0029] (3) By configuring the preheating assembly to include a low-power first preheating transformer, an ultrasonic inductor, a medium-power second preheating transformer, and a medium-frequency second preheating inductor, the pipe can be preheated with a low-power ultrasonic preheating first and then with a medium-power medium-frequency preheating, which is beneficial to increasing the heating speed of the pipe, reducing the induction heating time of the pipe, and improving the temperature uniformity of the pipe.

[0030] (4) The preheating assembly and the induction heating assembly of the present invention both use longitudinal magnetism to heat the pipe, which has a fast heating speed and high energy utilization rate.

[0031] (5) The present invention can achieve rapid heating of the pipe without placing the preheating component and the induction heating component in an atmosphere furnace, and improves the heating uniformity. Therefore, the equipment of the present invention is small in size and saves space. In addition, since an atmosphere furnace is not required, the equipment cost is low.

[0032] (6) The cooling system of the present invention is provided with an internal nozzle for extending into the internal space of the pipe to cool the inner wall of the pipe, thereby ensuring that the cooling speed of the inner and outer walls is consistent and improving the uniformity of the material.

[0033] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can be obvious from the description or understood by practicing the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0035] Figure 1 Schematic diagram of the device structure of an embodiment of the present invention; wherein red and blue represent circuit connections, green represents water inlet, and brown represents water outlet.

[0036] Reference numerals:

[0037] 1-transmission system; 2-1-first preheating transformer; 2-2-second preheating transformer; 3-1-first preheating inductor; 3-2-second preheating inductor; 4-1-first cooler; 4-2-second cooler; 5-cooling system; 6-1-first preheating induction coil; 6-2-second preheating induction coil; 7-1-first induction coil; 7-2-second induction coil; 8-inductor; 9-transformer; 10-cooling tower; 11-water purifier. DETAILED DESCRIPTION

[0038] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0039] In a first aspect, the present invention provides a device for improving the induction heating speed and heating uniformity of a pipe, comprising a transmission system 1, a preheating component, an induction heating component, a cooling system 5 and a cooling tower 10.

[0040] The transmission system 1 is used to transport the pipe, the preheating assembly is used to preheat the pipe, the induction heating assembly is used to heat the pipe to reach the complete austenitization temperature, the cooling system 5 is used to cool the heated pipe, and the cooling medium in the cooling tower 10 is used to cool the induction heating assembly and supply the cooling system. Both the preheating assembly and the induction heating assembly use longitudinal magnetism to heat the pipe.

[0041] The preheating assembly, the induction heating assembly and the cooling system are arranged in sequence along the traveling direction of the pipe. The cooling system 5 and the induction heating assembly are connected to the cooling tower 10 respectively.

[0042] like Figure 1 As shown, the preheating assembly includes a first preheating transformer 2-1, a first preheating inductor 3-1, a first preheating induction coil 6-1 and a first cooler 4-1. The first preheating transformer, the first preheating inductor and the first preheating induction coil are connected in sequence. The cooling medium in the first cooler 4-1 first flows through the first preheating inductor 3-1, and then flows from the first preheating inductor 3-1 through the first preheating transformer 2-1 and the first preheating induction coil 6-1 respectively.

[0043] The preheating transformer is used to provide a stable voltage and current to the preheating inductor. The preheating inductor is used to provide a current of a specific frequency to the preheating induction coil, thereby generating a magnetic field of a specific frequency. The preheating induction coil is used to provide a magnetic field to heat the pipe. The first cooler is used to cool the preheating induction coil, the preheating inductor and the preheating transformer.

[0044] Specifically, the power of the first preheating transformer is 70-90 kW, for example, 70 kW, 75 kW, 80 kW, 85 kW, 90 kW. The first preheating inductor is an ultrasonic inductor.

[0045] The power of the first preheating transformer is controlled to a low power of 70-90kW, and the preheating sensor adopts an ultrasonic sensor, which not only increases the temperature of the pipe but also shortens the subsequent induction heating time.

[0046] Alternatively, if Figure 1As shown, the preheating assembly also includes a second preheating transformer 2-2, a second preheating inductor 3-2, a second preheating induction coil 6-2 and a second cooler 4-2. The second preheating transformer, the second preheating inductor and the second preheating induction coil are connected in sequence. The cooling medium in the second cooler 4-2 first flows through the second preheating inductor 3-2, and then flows from the second preheating inductor 3-2 through the second preheating transformer 2-2 and the second preheating induction coil 6-2.

[0047] The preheating component is equipped with a dedicated cooler to prevent the cooling tower from being connected to too many devices that need to be cooled, causing the cooling water to heat up too high and resulting in insufficient cooling speed for the equipment.

[0048] Specifically, the power of the second preheating transformer is 140-170 kW, for example, 140 kW, 145 kW, 150 kW, 155 kW, 160 kW, 165 kW, 170 kW. The second preheating inductor is a medium frequency inductor.

[0049] After the above-mentioned low-power ultrasonic preheating, medium-power medium-frequency preheating is used to further improve the heating speed of the pipe, and because the coil frequency adopts medium frequency, it is beneficial to ensure the heating uniformity of the pipe.

[0050] The induction heating assembly includes a transformer 9, an inductor 8 and an induction coil connected in sequence. The induction coil includes a first induction coil 7-1 and a second induction coil 7-2. The first induction coil and the second induction coil are both connected to the inductor. The cooling medium in the cooling tower 10 flows through the transformer 9 and the inductor 8 respectively, and then flows from the inductor 8 through the first induction coil 7-1 and the second induction coil 7-2 respectively. The power of the transformer is 280-320kW, for example, 280kW, 290kW, 300kW, 310kW, 320kW. The greater the power of the transformer, the faster the heating speed. The inductor is a medium frequency inductor.

[0051] Preferably, the induction coils in the preheating assembly and the induction heating assembly are wrapped with insulating high-temperature resistant materials to reduce the risk of coil short circuits caused by collisions with pipes.

[0052] In addition, the device of the present invention further comprises four temperature detectors for detecting the temperature of the pipe when it leaves the corresponding coil.

[0053] The cooling tower 10 adopts a double water tank design, the cooling medium in one water tank is used to cool the induction coil, the inductor and the transformer of the induction heating component, and the cooling medium in the other water tank is used to supply cooling medium to the cooling system. The cooling system uses a booster pump to provide cooling circulation power.

[0054] Specifically, the cooling tower is 100L, of which 70L is used to cool the induction coil, sensor and transformer, and the remaining 30L is supplied to the cooling system.

[0055] In a preferred embodiment, a water purifier 11 is provided at the inlet of the cooling tower to purify the circulating water in the cooling tower to prevent impurities from entering the cooling tower and causing damage to the booster motor or the cooling tower.

[0056] In addition, a water purifier is also provided at the inlet of the cooler to purify the circulating water in the cooler and prevent impurities from entering the cold water cooler.

[0057] The transmission system adopts a high-input and low-output design, that is, the inlet end of the transmission system is higher than the outlet end, which prevents the cooling medium from flowing back to the induction coil position and reduces the heating rate.

[0058] In addition, the transmission rollers on the transmission system are driven by motors and connected by chains to ensure consistent linear speed. In addition, in order to prevent the steel pipe from rolling during the transmission process, a groove is provided in the middle of the transmission roller, and the pipe is placed in the groove.

[0059] In a preferred embodiment, the cooling system includes a nozzle for spraying on the surface of the pipe and an inner nozzle (not shown in the figure) for spraying on the inner wall of the pipe. The inner nozzle is used to extend into the inner space of the pipe to cool the inner wall of the pipe, thereby ensuring that the cooling speed of the inner and outer walls is consistent and improving the uniformity of the material.

[0060] In a second aspect, the present invention further provides a method for improving the induction heating speed and heating uniformity of a pipe, comprising the following steps:

[0061] Step 1: Check whether the water circuit and circuit are operating normally;

[0062] Step 2: The pipe is placed on the transmission system, the transformer switch of the preheating component and / or the induction heating component is turned on, the transmission system is started, and the pipe passes through the preheating induction coil of the preheating component, the induction coil of the induction heating component and the cooling system in sequence.

[0063] Among them, the material of the pipe is steel pipe, for example, Q235, Q345, Q195, Q215.

[0064] Specifically, step 1 includes starting the cooling tower water pump to check the operating status of the cooling water circuit, including the water purifier, induction coil, sensor, transformer and cooling system.

[0065] Step 1 also includes starting the cooling machine to check the operating status of the cooling water circuit, including the water purifier, the preheating induction coil, the preheating sensor, and the preheating transformer.

[0066] In step 2, turning on the transformer switch of the preheating component and / or the induction heating component includes:

[0067] Turn on the switch of the transformer 9 of the induction heating assembly, and connect the first induction coil 7-1 and the second induction coil 7-2;

[0068] Alternatively, the first preheating transformer 2-1 and the transformer 9 are turned on, and the first preheating induction coil 6-1, the first induction coil 7-1 and the second induction coil 7-2 are connected;

[0069] Alternatively, the first preheating transformer 2-1, the second preheating transformer 2-2 and the transformer 9 are switched on, and the first preheating induction coil 6-1, the second preheating induction coil 6-2, the first induction coil 7-1 and the second induction coil 7-2 are connected;

[0070] Alternatively, the switches of the first preheating transformer 2-1, the second preheating transformer 2-2 and the transformer 9 are turned on, and the first preheating induction coil 6-1, the first induction coil 7-1 and the second induction coil 7-2 are connected.

[0071] The device and method of the present invention are described in detail below with reference to specific embodiments.

[0072] Example 1

[0073] This embodiment provides a method for improving the induction heating rate and heating uniformity of a steel pipe (Q235), wherein the method includes connecting a first preheating induction coil 6-1 (5 turns, 80 kW, supersonic frequency), a first induction coil 7-1 (5 turns, 300 kW, medium frequency) and a second induction coil 7-2 (5 turns, 300 kW, medium frequency), and comprising the following steps:

[0074] Start the water pump of the cooling tower 10 and the chiller 4 to check the operating status of the cooling water circuit, including the water purifier 11, the first preheating induction coil 6-1, the first induction coil 7-1, the second induction coil 7-2, the first preheating sensor 3-1, the sensor 8, the first preheating transformer 2-1, the transformer 9 and the cooling system 5.

[0075] Place a Φ360mm*19mm steel pipe on the transmission system 1, turn on the switches of the first preheating transformer 2-1 (supersonic frequency) and transformer 9 (intermediate frequency), start the first preheating inductor 3-1 (80kW) and inductor 8 (300kW), and start the transmission system 1 after confirming that the circuit system is normal. The steel pipe passes through the first preheating induction coil 6-1, the first induction coil 7-1, the second induction coil 7-2 and the cooling system 5 in sequence. Record the moving speed of the steel pipe, the time it passes through the coil, and the temperature of each coil, and calculate the average temperature rise rate of the steel pipe. The results are shown in Table 1.

[0076] Example 2

[0077] This embodiment provides a method for improving the induction heating rate and heating uniformity of a steel pipe (Q235), wherein the method includes connecting a first preheating induction coil 6-1 (5 turns, 80 kW, supersonic frequency), a second preheating induction coil 6-2 (5 turns, 160 kW, medium frequency), a first induction coil 7-1 (5 turns, 300 kW, medium frequency) and a second induction coil 7-2 (5 turns, 300 kW, medium frequency), and comprising the following steps:

[0078] Start the water pump of the cooling tower 10 and the chiller 4 to check the operating status of the cooling water circuit, including the water purifier 11, the first preheating induction coil 6-1, the second preheating induction coil 6-2, the first induction coil 7-1, the second induction coil 7-2, the first preheating sensor 3-1, the second preheating sensor 3-2, the sensor 8, the first preheating transformer 2-1, the second preheating transformer 2-2, the transformer 9 and the cooling system 5.

[0079] Place a Φ360mm*19mm steel pipe on the transmission system 1, turn on the switches of the first preheating transformer 2-1 (supersonic frequency), the second preheating transformer 2-2 (intermediate frequency) and the transformer 9 (intermediate frequency), start the first preheating inductor 3-1 (80kW), the second preheating inductor 3-2 (160kW) and the inductor 8 (300kW), and start the transmission system 1 after confirming that the circuit system is normal. The steel pipe passes through the first preheating induction coil 6-1, the second preheating induction coil 6-2, the first induction coil 7-1, the second induction coil 7-2 and the cooling system 5 in sequence. Record the moving speed of the steel pipe, the time it passes through the coil, and the temperature of each coil, and calculate the average temperature rise rate of the steel pipe. The results are shown in Table 1.

[0080] Comparative Example 1

[0081] This comparative example provides a method for induction heating of a steel pipe (Q235), in which the first preheating induction coil 6-1, the second preheating induction coil 6-2 and the first induction coil 7-1 are not connected, and only the second induction coil 7-2 (5 turns, 300kW, medium frequency) is connected, comprising the following steps:

[0082] Start the water pump of the cooling tower 10 to check the operating status of the cooling water circuit, including the water purifier 11, the second induction coil 7-2, the inductor 8, the transformer 9 and the cooling system 5.

[0083] A Φ360mm*19mm steel pipe is placed on the transmission system 1, the switch of the transformer 9 (medium frequency) is turned on, the inductor 8 (300kW) is started, and the transmission system 1 is started after confirming that the circuit system is normal. The steel pipe passes through the second induction coil 7-2 and the cooling system 5 in sequence. The moving speed of the steel pipe, the time it passes through the coil, and the temperature of each coil are recorded, and the average temperature rise rate of the steel pipe is calculated. The results are shown in Table 1.

[0084] Table 1 Specific parameters and test results of the embodiments and comparative examples

[0085]

[0086] It can be seen from the data of Example 1, Example 2 and Comparative Example 1 in Table 1 that when coil preheating is not used (Comparative Example 1), the average heating rate is only 9.37°C / s, which is significantly lower than 17.22°C / s of Example 1 and 17.63°C / s of Example 2.

[0087] It can also be seen from the data of Example 1 and Comparative Example 1 that in order to make the steel rod have a comparable temperature when it leaves the coil (the temperature of the steel rod passing through the fourth section of the coil in Example 1 is 861°C, and the temperature of the steel rod passing through the fourth section of the coil in Comparative Example 1 is 862°C, which are comparable), it is necessary to reduce the moving speed and extend the time it takes to pass through the coil, thereby extending the production time and reducing the production efficiency.

[0088] It can also be seen from the data in Table 1 that when the coil preheating is not used (Comparative Example 1), the temperature difference between the core and the edge is as high as 35°C, while when the coil preheating is used (Examples 1 and 2), the temperature difference between the core and the edge is only 15°C and 17°C. This proves that the use of the equipment of the present invention can improve both the heating speed and the heating uniformity.

[0089] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A device for improving the induction heating speed and heating uniformity of pipes, characterized in that: Including transmission system, preheating component, induction heating component and cooling system; The transmission system is used to transport the pipe, the preheating assembly is used to preheat the pipe, the induction heating assembly is used to heat the pipe to reach a complete austenitizing temperature, and the cooling system is used to cool the heated pipe; The preheating assembly and the induction heating assembly both use longitudinal magnetism to heat the pipe; Along the traveling direction of the pipe, the preheating component, the induction heating component and the cooling system are arranged in sequence.

2. The device according to claim 1, characterized in that The preheating assembly comprises a first preheating transformer, a first preheating inductor and a first preheating induction coil connected in sequence; and a second preheating transformer, a second preheating inductor and a second preheating induction coil connected in sequence; The first preheating transformer is used to provide a stable voltage and current to the first preheating inductor; the first preheating induction coil is used to provide a magnetic field to heat the pipe; the first preheating inductor is used to provide a current of a specific frequency to the first preheating induction coil, thereby generating a magnetic field of a specific frequency.

3. The device according to claim 1, characterized in that The induction heating assembly comprises a transformer, an inductor and an induction coil connected in sequence; The induction coil includes a first induction coil and a second induction coil, and both the first induction coil and the second induction coil are connected to the inductor.

4. The device according to claim 3, characterized in that It also includes a cooling tower, and the cooling medium in the cooling tower is used to cool the induction heating component and supply the cooling system.

5. The device according to claim 1, characterized in that The induction coils in the preheating assembly and the induction heating assembly are both wrapped with insulating high-temperature resistant materials.

6. The device according to claim 4, characterized in that The cooling tower adopts a double water tank design, the cooling medium in one water tank is used to cool the induction heating component, and the cooling medium in the other water tank is used to supply cooling medium to the cooling system.

7. The device according to claim 1, characterized in that A groove is arranged in the middle of the transmission roller of the transmission system, and the pipe is placed in the groove.

8. The device according to claim 7, characterized in that The inlet end of the transmission system is higher than the outlet end.

9. The device according to claim 1, characterized in that The cooling system comprises a spray head for spraying on the surface of the pipe and an inner spray head for spraying on the inner wall of the pipe.

10. A method for improving the induction heating speed and heating uniformity of a pipe, characterized in that: The device according to any one of claims 1 to 9 comprises the following steps: Step 1: Check whether the water circuit and circuit are normal; Step 2: The pipe is placed on the transmission system, and the transformer switch of the preheating component and / or the induction heating component is turned on; the transmission system is started, and the pipe passes through the preheating induction coil of the preheating component, the induction coil of the induction heating component and the cooling system in sequence.

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