Electromagnetic heating device for rotor hot-mounting process
Patent Information
- Application Number
- CN202610670644.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-05-15
- Publication Date
- 2026-09-15
Smart Images
Figure CN122746589A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of electromagnetic heating technology, and more specifically, to an electromagnetic heating device for rotor heat fitting process. Background Technology
[0002] Currently, in existing rotor hot-fitting processes, impeller heating is mostly achieved using electric furnace heating or traditional insertion-type electromagnetic induction heating. Electric furnace heating is inefficient, suffers from significant heat loss, and struggles to guarantee heating uniformity. While insertion-type electromagnetic induction heating equipment offers advantages such as rapid response and high power, it also has significant technical drawbacks. During heating, the induced magnetic field provided by the insertion core concentrates the current within the impeller's inner diameter. However, the impeller material has poor thermal conductivity, leading to a large temperature difference between the inner and outer diameters, with the inner diameter temperature being much higher than the outer diameter. This radial temperature difference generates excessive thermal stress within the impeller, severely impacting assembly quality and service life. To control this temperature difference, intermittent heating is often employed, involving heating for a period followed by a shutdown to allow heat conduction and gradual reduction of the inner and outer ring temperatures to an acceptable range. However, this intermittent heating significantly prolongs the electromagnetic heating time, increasing production costs and reducing efficiency. Furthermore, existing electromagnetic heating devices generally lack effective insulation measures, allowing heat to easily conduct to the outer casing, resulting in energy waste. Summary of the Invention
[0003] This application aims to at least solve the problem of uneven radial temperature of the impeller caused by the traditional insertion electromagnetic induction heating method in related technologies. Because the induced magnetic field provided by the insertion iron core causes the current to concentrate in the inner diameter of the impeller, and the poor thermal conductivity of the impeller material results in a large temperature difference between the inner and outer diameters of the impeller, the intermittent heating method must be used in engineering to gradually reduce the temperature of the inner and outer rings of the impeller to an acceptable range, which leads to the technical problem of prolonged electromagnetic heating time and increased production costs.
[0004] To solve the above-mentioned technical problems, this application is implemented as follows: This application provides an electromagnetic heating device for rotor hot-fitting process, comprising: a housing; a U-shaped electromagnet disposed within the housing, the U-shaped electromagnet comprising a silicon steel sheet stack and a copper coil wound on the silicon steel sheet stack; an insert core movably connected to the open end of the U-shaped electromagnet, with both ends of the insert core movably connected to both ends of the U-shaped electromagnet to form a closed magnetic circuit when the U-shaped electromagnet is energized, for heating the inner diameter of the impeller to be heated; an iron core lifting mechanism mounted on the housing and drivenly connected to the insert core, for driving the insert core to move up and down, so that the insert core can be inserted into or detached from the inner hole of the impeller to be heated; an outer induction coil fixed on the housing and located below the insert core, and surrounding the outer periphery of the impeller to be heated, for heating the outer diameter of the impeller to be heated; and an impeller bearing assembly disposed on the housing and located below the outer induction coil, for supporting the impeller to be heated.
[0005] This application provides an electromagnetic heating device for rotor hot-fitting processes. Through the coordinated operation of a U-shaped electromagnet, an inserted iron core, an outer induction coil, and an iron core lifting mechanism, it achieves multiple functions including simultaneous internal and external heating, rapid temperature rise, and energy-saving heat preservation. Specifically, when the U-shaped electromagnet is energized, it forms a closed magnetic circuit with the inserted iron core, generating an induced current at the inner diameter of the impeller, causing the inner diameter to heat up. Simultaneously, when the outer induction coil, fixed to the outer casing, is energized, it generates an induced current at the outer diameter of the impeller, causing the outer diameter to heat up. The simultaneous action of the two heat sources ensures a uniform radial temperature distribution in the impeller, fundamentally solving the problem of excessive temperature difference caused by traditional insertion heating methods, avoiding excessive thermal stress inside the impeller, and improving assembly quality.
[0006] Additional aspects and advantages of this application will become apparent in the following description or may be learned by practice of this application. Attached Figure Description
[0007] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the structure of an electromagnetic heating device for rotor heat fitting process according to an embodiment of this application; Figure 2 for Figure 1 A schematic diagram of the AA cross-sectional structure of the electromagnetic heating device for rotor hot mounting process in the embodiment shown. Figure 3 for Figure 2 A schematic diagram of the BB cross-sectional structure of the electromagnetic heating device for rotor hot-fitting process in the embodiment shown. Figure 4 for Figure 2 A schematic diagram of the CC cross-section structure of the electromagnetic heating device for rotor hot mounting process in the embodiment shown. Figure 5 for Figure 1 One of the schematic diagrams of the core lifting mechanism in the electromagnetic heating device for rotor hot mounting process shown in the embodiment; Figure 6 for Figure 1 The second schematic diagram of the core lifting mechanism in the electromagnetic heating device for rotor hot mounting process shown in the embodiment.
[0008] in, Figures 1 to 6 The correspondence between the reference numerals and component names in the attached drawings is as follows: 100 Electromagnetic heating device for rotor hot fitting process, 101 Temperature measuring component, 1 Housing, 2 U-shaped electromagnet, 3 Inserted iron core, 4 Iron core lifting mechanism, 5 Outer ring induction coil, 6 Impeller load-bearing component, 7 Copper coil, 8 Rotating ring, 9 Internal support column, 10 Impeller support pad, 11 Load-bearing column. Detailed Implementation
[0009] To better understand the above-mentioned objectives, features, and advantages of this application, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.
[0010] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.
[0011] The following reference Figures 1 to 6 This application describes an electromagnetic heating apparatus for rotor heat-fitting processes provided according to some embodiments.
[0012] like Figure 1 , Figure 2 , Figure 3 and Figure 4As shown, an embodiment of this application provides an electromagnetic heating device 100 for rotor hot mounting process, comprising: a housing 1; a U-shaped electromagnet 2 disposed inside the housing 1, the U-shaped electromagnet 2 including silicon steel sheet stacks and a copper coil 7 wound on the silicon steel sheet stacks; an insert core 3 movably connected to the open end of the U-shaped electromagnet 2, and the two ends of the insert core 3 are respectively movably connected to the two ends of the U-shaped electromagnet 2 to form a closed magnetic circuit when the U-shaped electromagnet 2 is energized, for heating the inner diameter of the impeller to be heated; an iron core lifting mechanism 4 mounted on the housing 1 and drivenly connected to the insert core 3, for driving the insert core 3 to move up and down, so that the insert core 3 can be inserted into or detached from the inner hole of the impeller to be heated; an outer ring induction coil 5 fixed on the housing 1 and located below the insert core 3, and surrounding the outer periphery of the impeller to be heated, for heating the outer diameter of the impeller to be heated; and an impeller bearing assembly 6 disposed on the housing 1 and located below the outer ring induction coil 5, for supporting the impeller to be heated.
[0013] Specifically, such as Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, the electromagnetic heating device 100 for rotor hot-fitting process provided in the embodiments of this application includes a housing 1, a U-shaped electromagnet 2, an inserted iron core 3, an iron core lifting mechanism 4, an outer induction coil 5, and an impeller bearing assembly 6. The U-shaped electromagnet 2 is disposed inside the housing 1. The iron housing 1 is located on the outer layer of the entire device, protecting the U-shaped electromagnet 2 inside the device and acting as a closed magnetic field enclosure. The U-shaped electromagnet 2 includes a silicon steel sheet stack and a copper coil 7 wound on the silicon steel sheet stack. That is, the U-shaped electromagnet 2 is composed of silicon steel sheets and copper coil 7, with the copper coil 7 winding around the silicon steel sheets to achieve the function of an electromagnet. The inserted iron core 3 is movably connected to the open end of the U-shaped electromagnet 2, and both ends of the inserted iron core 3 are movably connected to the two ends of the U-shaped electromagnet 2, so as to form a closed magnetic circuit when the U-shaped electromagnet 2 is energized, for heating the inner diameter of the impeller to be heated. The iron core lifting mechanism 4 is mounted on the outer casing 1 and is driven by the insertion iron core 3. It drives the insertion iron core 3 to move up and down, allowing it to insert into or detach from the inner hole of the impeller to be heated. The outer ring induction coil 5 is fixed to the outer casing 1 and located below the insertion iron core 3, surrounding the outer circumference of the impeller to be heated, for heating the outer diameter of the impeller. The impeller support assembly 6 is mounted on the outer casing 1 and located below the outer ring induction coil 5, for supporting the impeller to be heated.
[0014] In this way, the U-shaped electromagnet 2 and the inserted iron core 3 form a closed magnetic circuit, generating an induced current at the inner diameter of the impeller to heat the inner diameter. At the same time, the outer induction coil 5 generates an induced current at the outer diameter of the impeller to heat the outer diameter. The simultaneous action of the inner and outer heat sources ensures a uniform radial temperature distribution of the impeller, avoiding the problem of excessive temperature difference caused by the traditional single inner diameter heating method. The iron core lifting mechanism 4 allows the inserted iron core 3 to be lowered during heating to form a closed magnetic circuit and raised after heating for easy impeller removal and placement, balancing heating efficiency and operational convenience. The outer shell 1 effectively seals the magnetic field to prevent leakage, and the impeller load-bearing component 6 provides stable support for the impeller, ensuring the stability and reliability of the heating process.
[0015] Compared with existing technologies, the electromagnetic heating device 100 for rotor hot assembly provided in this application has the following advantages: First, it provides synchronous heating inside and outside, eliminating radial temperature differences. The U-shaped electromagnet 2, in conjunction with the inserted iron core 3, heats the inner diameter of the impeller, while the outer induction coil 5 independently heats the outer diameter. This causes Joule heating to occur simultaneously in both the inner and outer diameters of the impeller, fundamentally solving the problem of excessive temperature differences between the inner and outer diameters caused by traditional insertion-type electromagnetic heating methods. This avoids thermal stress caused by temperature differences and significantly improves the assembly quality and service life of the impeller. Second, it significantly improves heating efficiency and shortens the production cycle. Synchronous heating of the inner and outer diameters greatly increases the overall heating rate of the impeller, eliminating the need for intermittent heating to wait for heat conduction. This effectively shortens the electromagnetic heating time, improves production efficiency, and reduces production costs. Third, it has a reasonable structural design and is convenient and safe to operate. The iron core lifting mechanism 4 can flexibly control the lifting and lowering of the inserted iron core 3 according to the needs of the heating process. During heating, it lowers to form a closed magnetic circuit to ensure heating effect; after heating, it rises to facilitate impeller placement and removal, avoiding interference between the workpiece and the iron core during workpiece handling. The outer shell 1 effectively seals the magnetic field, preventing magnetic field leakage from affecting the environment and operators. Fourth, it has significant energy-saving and heat-insulating effects. The outer shell 1 is made of magnetically conductive metal material, effectively sealing the magnetic field and reducing energy loss; the support pad in the impeller load-bearing component 6 uses heat-insulating material to prevent heat transfer from the impeller to the outer shell 1 after heating, reducing heat loss and further improving heating efficiency, achieving energy saving and consumption reduction.
[0016] Specifically, in current rotor hot-fitting processes, impeller heating is mostly achieved using electric furnace heating or traditional insertion-type electromagnetic induction heating. Electric furnace heating is inefficient, suffers from significant heat loss, and struggles to guarantee heating uniformity. While insertion-type electromagnetic induction heating equipment offers advantages such as rapid response and high power, it also has significant technical drawbacks. During heating, the induced magnetic field provided by the insertion core concentrates the current within the impeller's inner diameter. Given the impeller material's poor thermal conductivity, a large temperature difference arises between the inner and outer diameters, with the inner diameter temperature being much higher than the outer diameter. This radial temperature difference generates excessive thermal stress within the impeller, severely impacting assembly quality and service life. To control this temperature difference, intermittent heating is often employed, involving heating for a period followed by a shutdown to allow heat conduction and gradual reduction of the inner and outer ring temperatures to an acceptable range. However, this intermittent heating significantly prolongs the electromagnetic heating time, increasing production costs and reducing efficiency. Furthermore, existing electromagnetic heating devices generally lack effective insulation measures, allowing heat to easily conduct to the outer casing, resulting in energy waste. Therefore, there is an urgent need for an electromagnetic heating device that can achieve synchronous and uniform heating of the inner and outer diameters of the impeller, shorten the heating time, reduce thermal stress, and effectively maintain the temperature, so as to improve the heating quality and production efficiency of the rotor hot fitting process.
[0017] To address the shortcomings of existing technologies, such as Figure 1 , Figure 2 , Figure 3 and Figure 4As shown, the electromagnetic heating device 100 for rotor hot-fitting process provided in this application achieves multiple functions such as synchronous internal and external heating, rapid temperature rise, and energy-saving heat preservation through the coordinated operation of U-shaped electromagnet 2, inserted iron core 3, outer ring induction coil 5, and iron core lifting mechanism 4. Specifically, in the scenario of synchronous internal and external heating, after the U-shaped electromagnet 2 is energized, it forms a closed magnetic circuit with the inserted iron core 3, generating an induced current at the inner diameter of the impeller, causing the inner diameter to heat up; at the same time, after the outer ring induction coil 5 fixed on the outer shell 1 is energized, it generates an induced current at the outer diameter of the impeller, causing the outer diameter to heat up. The simultaneous action of the two heat sources inside and outside makes the radial temperature distribution of the impeller uniform, fundamentally solving the problem of excessive temperature difference caused by traditional insertion heating method, avoiding excessive thermal stress inside the impeller, and improving assembly quality. In the scenario of rapid temperature rise and high-efficiency production, synchronous heating of the inner and outer diameters greatly increases the overall heating speed of the impeller, eliminating the need to use intermittent heating to wait for heat conduction, significantly shortening the heating time, improving production efficiency, and reducing production costs. In scenarios requiring ease of operation and process compatibility, the core lifting mechanism 4 drives the insertion core 3 to move up and down. During heating, the insertion core 3 descends and connects with the U-shaped electromagnet 2 to form a closed magnetic circuit. After heating is complete, the insertion core 3 rises and disengages from the impeller's inner hole, facilitating the removal and placement of the impeller and balancing heating efficiency with ease of operation. In scenarios requiring energy conservation, heat preservation, and magnetic field sealing, the outer shell 1 is made of stainless steel or magnetically conductive metal material, effectively sealing the magnetic field and preventing magnetic field leakage from affecting the heating effect. The impeller support pad 10 is made of foam glass and is located at the bottom of the impeller, effectively preventing heat transfer from the impeller to the outer shell 1 after heating, reducing heat loss, improving heating efficiency, and achieving energy saving and consumption reduction. In scenarios requiring intelligent temperature control and precise heating, the temperature measuring component 101 collects the temperature information of the impeller's inner hole and outer circle in real time. Based on the temperature information, the controller precisely controls the energization status of the U-shaped electromagnet 2 and the outer induction coil 5, as well as the lifting action of the core lifting mechanism 4, to achieve automated and precise control of the heating process and ensure consistent heating quality.
[0018] In some embodiments, optionally, such as Figure 1 and Figure 2 As shown, the silicon steel sheet stack of the U-shaped electromagnet 2 is composed of multiple silicon steel sheets stacked layer by layer along the longitudinal direction of the U-shaped electromagnet 2, and the copper coil 7 is wound around the three sides of the U-shaped electromagnet 2 respectively.
[0019] Specifically, such as Figure 2As shown, the U-shaped electromagnet 2 adopts a silicon steel sheet laminated structure. Multiple silicon steel sheets are stacked layer by layer along the longitudinal direction of the U-shaped electromagnet 2, that is, the extension direction of the U-shaped opening, to form an integral U-shaped magnetic core structure. Copper coils 7 are wound on the three sides of the U-shaped electromagnet 2, that is, copper coils 7 are wound on the bottom side and the two sides of the U-shape. When alternating current is applied to the copper coils 7, an alternating magnetic field is generated inside the U-shaped silicon steel sheet laminate. As a highly permeable magnetic material, the silicon steel sheets efficiently guide the magnetic field to the open end of the U-shaped electromagnet 2, providing a strong magnetic field input for the inserted iron core 3. The silicon steel sheet laminated structure can effectively reduce eddy current loss and hysteresis loss, and improve electromagnetic conversion efficiency; the uniform winding of the copper coils 7 on the three sides makes the magnetic field distribution more uniform and symmetrical, enhancing the magnetization effect on the inserted iron core 3. In this way, through the synergistic design of the silicon steel sheet stacked structure and the three-sided wound copper coil 7, the U-shaped electromagnet 2 can efficiently and stably generate an induced magnetic field, providing sufficient magnetic energy for the inserted iron core 3, ensuring that the impeller inner diameter receives a sufficiently strong induced current, and achieving efficient and uniform inner diameter heating.
[0020] In some embodiments, optionally, such as Figure 1 and Figure 2 As shown, the inserted iron core 3 is composed of multiple silicon steel sheets stacked layer by layer along the longitudinal direction of the inserted iron core 3.
[0021] Specifically, such as Figure 2 As shown, the insert core 3 adopts the same silicon steel sheet stacked structure as the U-shaped electromagnet 2. Multiple silicon steel sheets are stacked layer by layer along the longitudinal direction of the insert core 3, i.e., the axial direction of the insert core 3, to form an integral columnar core structure. An insulating coating is provided between the silicon steel sheets to block the flow path of eddy currents between the sheets. When the U-shaped electromagnet 2 is energized to generate a magnetic field, the magnetic field is conducted to the insert core 3 through the open end of the U-shaped electromagnet 2, forming a uniform magnetic field parallel to the axis of the insert core 3 inside the silicon steel sheets. As a component of the magnetic circuit, the insert core 3 efficiently guides the magnetic field to the impeller inner diameter region, inducing a current in the impeller inner diameter, and then heating the inner diameter through the Joule heating effect. The silicon steel sheet stacked structure effectively reduces the eddy current loss and hysteresis loss of the insert core 3 itself, reduces core heating, and improves magnetic energy utilization; at the same time, the uniform magnetic field distribution ensures that the intensity of the induced current in the circumferential direction of the impeller inner diameter is consistent, making the inner diameter heating more uniform and stable. In this way, the silicon steel sheet stacking design inserted into the iron core 3 achieves efficient and low-loss magnetic energy conduction, providing a uniform and stable induction heating effect for the impeller inner diameter, and further ensuring the uniformity of the impeller radial temperature.
[0022] In some embodiments, optionally, such as Figure 5 and Figure 6As shown, the iron core lifting mechanism 4 includes: an internal support column 9, which is fixedly mounted on the outer shell 1; a rotating ring 8, which is rotatably mounted on the internal support column 9, and the outer circumferential surface of the rotating ring 8 is in frictional contact with the inserted iron core 3; and a drive motor, which is fixed on the outer shell 1 and whose output shaft is drivenly connected to the rotating ring 8, for driving the rotating ring 8 to rotate, so as to drive the inserted iron core 3 to rise and fall through friction.
[0023] Specifically, such as Figure 5 and Figure 6 As shown, the core lifting mechanism 4 uses friction transmission to achieve precise lifting control of the inserted core 3. The internal support column 9 is vertically fixed to the outer shell 1, providing stable rotational support for the rotating ring 8. The rotating ring 8 is rotatably mounted on the internal support column 9, and its outer circumferential surface forms a friction contact pair with the side wall of the inserted core 3. The drive motor is fixed to the outer shell 1, and its output shaft is driven by the rotating ring 8 through a transmission mechanism. When the drive motor starts, the output shaft drives the rotating ring 8 to rotate around the internal support column 9. The outer circumferential surface of the rotating ring 8 converts the rotational motion into the linear lifting motion of the inserted core 3 through static friction with the inserted core 3. By controlling the forward and reverse rotation of the drive motor, the rising or falling of the inserted core 3 can be achieved; by controlling the rotation angle of the drive motor, the lifting displacement of the inserted core 3 can be precisely adjusted. When the impeller needs to be heated, the drive motor drives the rotating ring 8 to rotate in the forward direction, causing the inserted iron core 3 to descend into the inner hole of the impeller and connect with both ends of the U-shaped electromagnet 2 to form a closed magnetic circuit. After heating is completed, the drive motor rotates in the reverse direction, causing the inserted iron core 3 to rise and disengage from the inner hole of the impeller, facilitating the removal and placement of the impeller. In this way, the friction-driven iron core lifting mechanism 4 achieves precise control of the lifting motion of the inserted iron core 3. The structure is simple and reliable, with a rapid response, providing reliable operational assurance for the internal and external synchronous heating process, while avoiding the maintenance costs and failure risks associated with complex transmission mechanisms.
[0024] In some embodiments, optionally, such as Figure 1 and Figure 2 As shown, the outer ring induction coil 5 is arranged around the axial direction of the impeller to be heated, and the axial winding length is 20mm~40mm, and the number of winding layers along the radial direction of the impeller to be heated is 20 layers~30 layers.
[0025] Specifically, such as Figure 1 and Figure 2As shown, the outer induction coil 5 adopts an axial winding arrangement, meaning the winding direction of the coil is parallel to the impeller's axis. This ensures the magnetic field generated by the coil is perpendicular to the impeller's outer diameter surface, thereby efficiently generating an induced current at the impeller's outer diameter. The axial winding length is controlled within the range of 20mm to 40mm. This dimension matches the axial height of the impeller hub, ensuring the magnetic field covers the entire heating area of the impeller's outer diameter. This avoids insufficient heating due to an excessively short winding length or wasted magnetic field due to an excessively long winding length. The radial winding layer is controlled within the range of 20 to 30 layers. This multi-layer winding structure enhances the magnetic field strength, ensuring sufficient induced current density at the impeller's outer diameter for rapid and uniform heating. The coil is wound with copper wire, and insulation layers are placed between the layers to ensure electrical safety. In this way, through the coordinated design of axial winding length and radial winding layers, the outer induction coil 5 can generate an alternating magnetic field with sufficient strength and uniform distribution that matches the outer diameter of the impeller, so that the induced current density at the outer diameter of the impeller is uniform, achieving efficient and uniform outer diameter heating. This forms a synchronous heating effect with the inner diameter heating of the inserted iron core 3, which together ensures the uniformity of the radial temperature of the impeller and avoids the generation of thermal stress.
[0026] In some embodiments, optionally, such as Figure 2 and Figure 4 As shown, the impeller support assembly 6 includes: an impeller support pad 10, which is disposed at the bottom of the outer ring induction coil 5 and located below the impeller to be heated, for supporting the impeller to be heated and preventing heat from being conducted to the outer casing 1; and a plurality of support columns 11, which are spaced apart on the lower side of the impeller support pad 10 for supporting the impeller support pad 10.
[0027] Specifically, such as Figure 2 and Figure 4As shown, the impeller support assembly 6 adopts a double-layer structure design to achieve stable support and effective heat insulation for the impeller. The impeller support pad 10 is disc-shaped and is located at the bottom of the outer induction coil 5, directly below the impeller to be heated. Its upper surface is in direct contact with the bottom of the impeller, bearing the entire weight of the impeller. The impeller support pad 10 is made of a low thermal conductivity insulation material, which, while supporting the impeller, effectively blocks the conduction of heat from the heated impeller to the outer casing 1, reducing heat loss and improving heating efficiency. Multiple support columns 11 are spaced apart on the underside of the impeller support pad 10. The upper end of the support column 11 is fixedly connected to the impeller support pad 10, and the lower end is fixed to the bottom of the outer casing 1, providing stable support for the impeller support pad 10 and ensuring its structural stability when bearing the weight of the impeller and the thermal stress during the heating process. The spacing between the support columns 11 facilitates air circulation, further reducing the downward conduction of heat. In this way, through the coordinated cooperation of the impeller support pad 10 and the load-bearing column 11, the impeller load-bearing component 6 provides reliable support while achieving effective heat insulation, avoiding ineffective heat loss to the outer shell 1, improving energy utilization, and ensuring the stability and consistency of heating effect.
[0028] In some embodiments, optionally, such as Figure 2 and Figure 4 As shown, the impeller support pad 10 is made of foam glass.
[0029] Specifically, such as Figure 2 As shown, the impeller support pad 10 is made of foamed glass. In this embodiment, foamed glass is chosen for the impeller support pad 10. Its extremely low thermal conductivity effectively blocks heat conduction from the heated impeller to the outer casing 1, reducing heat loss and improving thermal efficiency. Simultaneously, the excellent high-temperature resistance of foamed glass allows it to withstand the high-temperature environment during impeller heating without deformation or softening. Furthermore, foamed glass possesses sufficient mechanical strength to reliably support the weight of the impeller without crushing or cracking, ensuring the impeller's stable position during heating. Thus, by using foamed glass as the material for the impeller support pad 10, a balance between excellent thermal insulation and reliable mechanical support is achieved, effectively reducing ineffective heat loss to the outer casing 1, improving energy utilization, ensuring the stability and consistency of the heating effect, and extending the service life of the device.
[0030] In some embodiments, optionally, such as Figure 1 and Figure 2 As shown, the outer shell 1 is made of stainless steel with a thickness of 2mm to 5mm, and is used to enclose the magnetic field and prevent magnetic field leakage.
[0031] Specifically, such as Figure 1 and Figure 2As shown, the outer shell 1 is made of stainless steel, utilizing its magnetic permeability to form a complete magnetic shield. The thickness of the outer shell 1 is controlled within the range of 2mm to 5mm. This thickness selection balances structural strength and magnetic shielding effectiveness: too small a thickness may result in incomplete magnetic shielding, with some magnetic field leaking into the external space; too large a thickness increases material costs and device weight, with limited improvement in magnetic shielding effectiveness. When the U-shaped electromagnet 2 and the outer induction coil 5 are energized, the generated alternating magnetic field is confined within the stainless steel outer shell 1, preventing it from penetrating into the external space and effectively preventing magnetic field leakage from affecting the surrounding environment and operators. Simultaneously, as a component of the magnetic circuit, the closed structure of the outer shell 1 helps guide the magnetic field to the effective heating area, reducing magnetic energy loss and improving heating efficiency. Stainless steel also possesses excellent corrosion resistance and mechanical strength, enabling it to withstand thermal radiation and thermal stress during the heating process without deformation or rust. Thus, through the reasonable thickness design and material selection of the stainless steel outer shell 1, effective magnetic field enclosure is achieved, ensuring the safety of the operating environment, reducing magnetic energy loss, improving heating efficiency, and simultaneously ensuring the structural stability and long-term durability of the device.
[0032] In some embodiments, optionally, such as Figure 1 and Figure 2 As shown, the inserted iron core 3 is coaxially arranged with the inner diameter of the impeller to be heated, and the outer ring induction coil 5 is coaxially arranged with the outer diameter of the impeller to be heated.
[0033] Specifically, such as Figure 1 and Figure 2 As shown, the axis of the inserted iron core 3 coincides with the axis of the inner hole of the impeller to be heated, ensuring that the gap between the outer circumference of the inserted iron core 3 and the inner wall of the impeller is uniform after the iron core 3 is inserted into the impeller's inner hole. The central axis of the outer induction coil 5 coincides with the axis of the impeller to be heated, so that when the coil surrounds the outer diameter of the impeller, the radial distance between the coil and the outer diameter surface of the impeller is equal everywhere. This coaxial arrangement ensures the axial symmetry of the magnetic field distribution: when the U-shaped electromagnet 2 is energized, the magnetic field generated by the inserted iron core 3 is uniformly distributed along the circumference of the impeller's inner diameter, making the induced current density equal at all points on the inner diameter and the heating temperature consistent; when the outer induction coil 5 is energized, the magnetic field it generates is uniformly distributed along the circumference of the impeller's outer diameter, making the induced current density equal at all points on the outer diameter and the heating temperature consistent. If the inserted iron core 3 or the outer induction coil 5 is not coaxial with the impeller, it will lead to uneven magnetic field distribution, with a strong magnetic field on one side of the impeller and a weak magnetic field on the other side, causing temperature differences in the circumferential direction, and thus generating uneven thermal stress and deformation. In this way, the coaxiality design ensures the uniformity of heating in the circumferential direction of the impeller's inner and outer diameters, avoiding local overheating or underheating caused by eccentricity, further ensuring the uniform distribution of the overall temperature of the impeller, eliminating the root cause of thermal stress, and improving the heating quality and assembly accuracy of the impeller.
[0034] In some embodiments, optionally, such as Figure 1 As shown, it also includes: a temperature measuring component 101, which is installed on the housing 1 and located on the outer periphery of the impeller to be heated, for real-time acquisition of temperature information of the inner hole and outer circle of the impeller to be heated; and a controller, which is electrically connected to the temperature measuring component 101, the U-shaped electromagnet 2, the outer ring induction coil 5 and the iron core lifting mechanism 4 respectively. The controller is configured to receive temperature information and control the energization state of the U-shaped electromagnet 2 and the outer ring induction coil 5 and the lifting action of the iron core lifting mechanism 4 based on the temperature information.
[0035] Specifically, such as Figure 1 As shown, the temperature measuring component 101 is mounted on the housing 1, with its sensing end facing the impeller to be heated. It can employ temperature sensing elements such as infrared temperature sensors or thermocouples to collect real-time temperature information of the impeller's inner bore and outer circumference. The temperature measuring component 101 can be configured with multiple temperature measuring points, corresponding to different positions on the impeller's inner bore wall and outer circumference surface, to comprehensively monitor the radial temperature distribution. The controller uses an industrial control chip or a programmable logic controller, and is electrically connected to the temperature measuring component 101, the U-shaped electromagnet 2, the outer ring induction coil 5, and the iron core lifting mechanism 4. The controller receives real-time temperature information collected by the temperature measuring component 101 and compares it with the preset heating process curve. When the inner hole temperature reaches the first preset temperature and the temperature difference between the inner and outer rings is within a reasonable range, the controller maintains the energization of the U-shaped electromagnet 2 and the outer ring induction coil 5, continuing heating until the target temperature is reached. When the temperature difference between the inner and outer rings exceeds the allowable range, the controller can adjust the power distribution of the U-shaped electromagnet 2 and the outer ring induction coil 5 or temporarily cut off the power supply, waiting for the temperature difference to decrease before continuing heating. Before heating begins, the controller controls the iron core lifting mechanism 4 to lower and insert the iron core 3 into the impeller inner hole. After heating is completed, the controller controls the iron core lifting mechanism 4 to rise and insert the iron core 3, facilitating the removal and placement of the impeller. In this way, through the coordinated operation of the temperature measuring component 101 and the controller, closed-loop control of the heating process is achieved. The heating parameters can be adjusted in real time according to the actual temperature of the impeller, ensuring that the inner hole and outer ring of the impeller reach the target temperature synchronously and uniformly. This avoids the uncertainty and error of manual operation, improves the consistency of heating quality and process stability, and automates the heating process, reducing the labor intensity of operators and their reliance on experience and skills.
[0036] In specific applications, such as Figure 1 As shown, the purpose of this application is to provide an electromagnetic heating device 100 for rotor hot mounting process, so as to solve the problem of uneven temperature along the inner and outer diameter directions during the electromagnetic heating process of impeller mentioned in the background art.
[0037] Specifically, the electromagnetic heating device 100 for rotor hot mounting process provided in this application mainly includes: a shell 1, a U-shaped electromagnet 2, an inserted iron core 3, an iron core lifting mechanism 4, an outer ring induction coil 5, an impeller load-bearing component 6, a copper coil 7, a rotating ring 8, an internal support column 9, and an impeller support pad 10.
[0038] The outer casing 1 is made of iron and is located on the outermost layer of the entire device. It serves two purposes: firstly, it protects the internal copper coil 7, U-shaped electromagnet 2, and impeller load-bearing components, and provides a platform for the heated impeller; secondly, it prevents the electromagnetic field inside the device from leaking into the outside air and affecting the distribution of the induced current inside the impeller. Specifically, the outer casing 1 is 2mm thick and made of stainless steel.
[0039] Specifically, such as Figure 2 As shown, the U-shaped electromagnet 2 is composed of a copper coil 7 and silicon steel sheets. The silicon steel sheets are arranged longitudinally along the U-shaped magnet, stacked layer by layer. Each silicon steel sheet measures 800mm × 1mm × 16mm, and 20 layers are stacked at each of the three sides of the U-shape. A copper coil 7 is wound around each side, with a winding length of 40cm and 20 layers. When alternating current is applied to the copper coil 7, an induced magnetic field is generated within the silicon steel sheets arranged in the U-shape. The two components combine to form an electromagnet.
[0040] Specifically, such as Figure 2 As shown, the inserted iron core 3 is used to connect the N and S poles of the U-shaped magnet. It is made of stacked silicon steel sheets, each measuring 800mm × 1mm × 8mm, with a total of 20 layers. The magnetic field generated by the U-shaped electromagnet 2 causes a parallel magnetic field parallel to the axis of the silicon steel sheets to be generated inside the silicon steel sheets, which in turn induces a current in the inner diameter of the impeller, resulting in Joule heating.
[0041] Specifically, such as Figure 2 , Figure 5 and Figure 6 As shown, the iron core lifting mechanism 4 is used to control the distance of the inserted iron core 3 into the inner diameter of the impeller. When the impeller is electromagnetically heated, the iron core 3 needs to be fully inserted into the inner diameter of the impeller and connected to the two stages of the U-shaped electromagnet 2 through the iron core lifting mechanism 4. After the impeller is heated, the iron core 3 is lifted by the lifting mechanism to facilitate the handling of the impeller. The iron core lifting mechanism 4 includes a rotating ring 8 and an internal support column 9. The internal support column 9 provides support for the rotating ring 8, which is driven by a motor. After its rotation, the insertion distance of the iron core 3 is adjusted by the friction between its outer surface and the iron core 3.
[0042] Specifically, such as Figure 2As shown, the outer induction coil 5 is arranged near the outer diameter of the heating impeller. It is wound tangentially along the outer diameter of the impeller, with an axial winding thickness of 20 mm and 20 vertical winding layers. It uses copper wire and carries alternating current internally. Through the principle of electromagnetic induction, it induces a current at the outer diameter of the impeller, thereby generating Joule heating.
[0043] Specifically, such as Figure 3 and Figure 4 As shown, multiple load-bearing columns 11 are located below the impeller support pad 10. These six columns, made of stainless steel, each have a cross-sectional area of 40mm × 40mm and serve to support the impeller support pad 10. The impeller support pad 10 is made of foam glass, is disc-shaped with a thickness of 40mm, and a radius of 800mm~1000mm. It serves to insulate the impeller from heat transfer.
[0044] The beneficial effects of this application are as follows: by using the U-shaped electromagnet 2 and the inserted iron core 3 to form an induced current at the inner diameter of the impeller, and at the same time, the outer induction coil 5 forms an induced current at the outer diameter of the impeller. The induced current existing at both the inner and outer diameters will cause Joule heating to be generated at both the inner and outer diameters of the impeller, thereby reducing the temperature difference between the inner and outer diameters of the impeller.
[0045] In the description of this application, the term "multiple" refers to two or more. Unless otherwise expressly defined, the terms "upper," "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. The terms "connection," "installation," "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.
[0046] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0047] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. An electromagnetic heating device for a hot-chamber process for rotors, characterized in that, include: shell; A U-shaped electromagnet is disposed inside the housing. The U-shaped electromagnet includes a silicon steel sheet stack and a copper coil wound on the silicon steel sheet stack. An iron core is inserted and movably connected to the open end of the U-shaped electromagnet, and the two ends of the inserted iron core are respectively movably connected to the two ends of the U-shaped electromagnet to form a closed magnetic circuit when the U-shaped electromagnet is energized, which is used to heat the inner diameter of the impeller to be heated. The iron core lifting mechanism is installed on the outer shell and is connected to the insert iron core drive to drive the insert iron core to lift and lower, so that the insert iron core can be inserted into or detached from the inner hole of the impeller to be heated. An outer induction coil is fixed to the outer casing and located below the inserted iron core, and is arranged around the outer periphery of the impeller to be heated, for heating the outer diameter of the impeller to be heated; An impeller support assembly is mounted on the housing and located below the outer ring induction coil, and is used to support the impeller to be heated.
2. The electromagnetic heating device for a rotor hot-mounting process according to claim 1, characterized by, The U-shaped electromagnet is composed of multiple silicon steel sheets stacked layer by layer along the longitudinal direction of the U-shaped electromagnet, and the copper coils are wound around the three sides of the U-shaped electromagnet respectively.
3. The electromagnetic heating device for a rotor hot-mounting process according to claim 1, characterized by, The insert core is composed of multiple silicon steel sheets stacked layer by layer along the longitudinal direction of the insert core.
4. The electromagnetic heating device for a rotor hot-mounting process according to claim 1, characterized by, The core lifting mechanism includes: Internal support columns are fixedly installed on the outer shell; The rotating ring is rotatably mounted on the internal support column, and the outer circumferential surface of the rotating ring is in frictional contact with the inserted iron core. A drive motor is fixed to the housing, and its output shaft is driven to the rotating ring to drive the rotating ring to rotate, thereby driving the inserted iron core to rise and fall through friction.
5. The electromagnetic heating device for rotor hot-mounting process according to claim 1, characterized by, The outer ring induction coil is arranged around the axial direction of the impeller to be heated, with an axial winding length of 20mm to 40mm and 20 to 30 layers wound in the radial direction of the impeller to be heated.
6. The electromagnetic heating device for rotor hot-mounting process according to claim 1, characterized by, The impeller load-bearing component includes: An impeller support pad is disposed at the bottom of the outer ring induction coil and located below the impeller to be heated, for supporting the impeller to be heated and preventing heat from being conducted to the outer casing; Multiple load-bearing columns are spaced apart on the underside of the impeller support pad layer to support the impeller support pad layer.
7. The electromagnetic heating device for a rotor hot-mounting process according to claim 6, characterized by The impeller support pad is made of foam glass.
8. The electromagnetic heating device for a rotor hot-mounting process according to claim 1, characterized by, The outer shell is made of stainless steel and has a thickness of 2mm to 5mm. It is used to seal the magnetic field and prevent magnetic field leakage.
9. The electromagnetic heating device for rotor hot-mounting process according to claim 1, characterized by, The inserted iron core is coaxially arranged with the inner diameter of the impeller to be heated, and the outer ring induction coil is coaxially arranged with the outer diameter of the impeller to be heated.
10. The electromagnetic heating device for a rotor hot-mounting process according to any one of claims 1 to 9, characterized in that, Also includes: A temperature measuring component is installed on the housing and located on the outer periphery of the impeller to be heated, for real-time acquisition of temperature information of the inner hole and outer circle of the impeller to be heated; The controller is electrically connected to the temperature measuring component, the U-shaped electromagnet, the outer coil induction coil, and the core lifting mechanism, respectively. The controller is configured to receive the temperature information and control the energizing state of the U-shaped electromagnet and the outer coil induction coil, as well as the lifting action of the core lifting mechanism, based on the temperature information.