A monitoring alarm system for medium frequency furnace and medium frequency furnace

Abstract

The utility model relates to a monitoring and alarm system for a medium frequency furnace and a medium frequency furnace, wherein the monitoring and alarm system comprises: a furnace body, the outer wall of which is wound with an induction coil; a plurality of thermal sensing modules, which are arranged between different turns of the induction coil; and a circulating temperature measuring device, which is electrically connected to each of the thermal sensing modules; wherein, when the circulating temperature measuring device detects that the temperature of any of the thermal sensing modules exceeds a threshold value, the circulating temperature measuring device performs an alarm. The utility model has the advantages of digital recording, high monitoring accuracy, wide application range, convenient layout and low equipment cost, and solves the problems of false alarms and missed alarms caused by water vapor during the firing process of the medium frequency furnace.

Description

Technical Field

[0001] The utility model relates to the technical field of metal smelting, in particular to a monitoring alarm system of a medium frequency furnace and the medium frequency furnace. Background Art

[0002] One of the main safety hazards facing the medium frequency furnace body is leakage and penetration accidents. Such incidents may cause the copper tube of the induction coil to rupture. Once the copper tube is damaged, the cooling water will come into direct contact with the high-temperature molten liquid of more than 1000°C. The instantaneous temperature difference will cause the cooling water to evaporate violently and produce a large amount of steam. The huge accumulated energy will be released instantly, causing serious damage or even explosion. Therefore, how to effectively prevent leakage and penetration accidents in medium frequency furnaces has become a core issue of concern for medium frequency furnace manufacturers and metallurgical enterprises in recent years.

[0003] In the prior art, there are many defects in the leakage warning of the medium frequency furnace, for example, false alarms caused by uneven moisture content in the charge. For another example, when the resistivity of the furnace refractory material changes due to special process conditions or alloy composition, the alarm system may not be able to respond in time, resulting in missed alarms. Therefore, there is room for improvement. Utility Model Content

[0004] In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a monitoring alarm system and an intermediate frequency furnace for solving the technical problems of false alarms, missed alarms, etc. in the prior art leakage furnace warning system.

[0005] In order to achieve the above-mentioned purpose and other related purposes, the utility model provides a monitoring and alarm system for a medium frequency furnace, comprising:

[0006] A furnace body, the outer wall of which is wound with an induction coil;

[0007] A plurality of thermal sensing modules are disposed between different turns of the induction coil; and

[0008] A circulating temperature measuring device electrically connected to each of the thermal sensing modules;

[0009] When the circulating temperature measuring device detects that the temperature of any of the thermal sensing modules exceeds a threshold value, the circulating temperature measuring device generates an alarm.

[0010] In one embodiment of the present invention, the furnace body comprises:

[0011] A heat-insulating layer, a receiving cavity is formed at a center thereof; and

[0012] A crucible is arranged in the containing cavity, and the crucible is used to contain metal materials.

[0013] In one embodiment of the utility model, the monitoring and alarm system of the medium frequency furnace further includes a plurality of bottom sensor modules, the bottom sensor modules are buried at the bottom of the thermal insulation layer, and the bottom sensor modules are electrically connected to the circulating temperature measuring device.

[0014] In one embodiment of the present invention, the circulating temperature measuring device comprises:

[0015] a controller, electrically connected to the thermal sensing module and the bottom sensing module, for recording historical temperature curves of the thermal sensing module and the bottom sensing module; and

[0016] an alarm, electrically connected to the controller;

[0017] When the controller detects that the temperature of any one of the thermal sensing modules and / or any one of the bottom sensing modules exceeds a threshold value, the controller activates the alarm.

[0018] In one embodiment of the utility model, the monitoring and alarm system of the intermediate frequency furnace further includes:

[0019] Refractory cement, the refractory cement is filled between the turns of the induction coil; and

[0020] The magnetic yoke is arranged on the outer side of the induction coil.

[0021] In one embodiment of the present invention, the thermal sensing module comprises:

[0022] a thermocouple, embedded in the refractory mortar; and

[0023] The insulating tube is sleeved on the thermocouple.

[0024] In an embodiment of the present invention, the distance between the thermal sensing module and the turns of the induction coils on two adjacent sides is greater than or equal to 1 cm.

[0025] In one embodiment of the present invention, the plurality of thermal sensing modules are evenly distributed along the busbar direction of the furnace body.

[0026] In an embodiment of the present invention, along the busbar direction of the furnace body, the distance between two adjacent thermal sensing modules is in the range of 15 cm to 40 cm.

[0027] The utility model also provides a medium frequency furnace, comprising a monitoring and alarm system for the medium frequency furnace as described in any one of the above items.

[0028] As described above, the utility model provides a monitoring and alarm system for a medium frequency furnace and a medium frequency furnace, which have the following beneficial effects: In summary, the utility model proposes a monitoring and alarm system for a medium frequency furnace and a medium frequency furnace, which can effectively avoid false alarms, missed alarms, etc. caused by water vapor during the burning process of the medium frequency furnace, and has the advantages of digital recording, high monitoring accuracy, wide application range, convenient layout and low equipment cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Shown is a structural schematic diagram of a monitoring and alarm system for a medium frequency furnace provided by the utility model.

[0030] Figure 2 The graph shows the relationship between the temperature of the thermal sensor module and the thickness of the furnace body in one embodiment of the present invention.

[0031] Component number description

[0032] 100, furnace body; 110, heat insulation layer; 120, crucible;

[0033] 200. Thermal sensing module;

[0034] 300, circulating temperature measuring device; 310, controller; 320, alarm;

[0035] 400, induction coil;

[0036] 500, refractory mortar;

[0037] 600, yoke;

[0038] 700, bottom sensor module;

[0039] 800. Relationship curve. DETAILED DESCRIPTION

[0040] The following describes the implementation of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and the features in the embodiments can be combined with each other without conflict. It should also be understood that the terms used in the embodiments of the present invention are intended to describe specific implementation schemes, rather than to limit the scope of protection of the present invention. The test methods for which specific conditions are not specified in the following examples are usually carried out under conventional conditions or under the conditions recommended by the manufacturers.

[0041] See also Figure 1-2It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings in this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the utility model, so they have no substantial technical significance. Any structural modification, change in proportion relationship or adjustment of size, without affecting the effects and purposes that can be achieved by the utility model, should still fall within the scope of the technical content disclosed by the utility model. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the utility model. The change or adjustment of their relative relationship should also be regarded as the scope of the implementation of the utility model without substantially changing the technical content.

[0042] It should be noted that the medium frequency furnace is a high-efficiency electric furnace that uses the principle of electromagnetic induction to heat and melt metals. Its core function is to convert the input 50HZ three-phase industrial frequency AC into DC through a rectification step, and then invert it into an adjustable medium frequency current, with a frequency range of usually above 300HZ to 1000HZ. This medium frequency current forms an alternating flow through the capacitor and the induction coil, generating dense magnetic field lines inside the induction coil, and then performing high-intensity magnetic cutting on the metal material in the coil, inducing huge eddy currents, and achieving efficient heating and melting processes.

[0043] The utility model provides a monitoring and alarm system for a medium frequency furnace and a medium frequency furnace, which relates to the technical field of metal smelting, and can be specifically applied to the monitoring and early warning of accidents such as leakage and penetration of the medium frequency furnace body. For example, during the sintering operation of the medium frequency furnace, the alarm system may give a false alarm due to the uneven moisture content in the charge. For another example, when smelting a specific alloy or performing a special process, the resistivity of the refractory material may change due to the influence of the process conditions or the alloy composition, or when using a graphite crucible to smelt non-metallic materials, since the non-metallic material itself is not conductive, if cracks appear in the crucible, the alarm system may fail to respond in time. Moreover, as the service life of the furnace is extended, the detection electrode will be oxidized or react chemically with the refractory material in the process of repeatedly being subjected to a high temperature environment, resulting in the degradation of its conductive performance, and ultimately failing to issue a penetration alarm in time, increasing the risk of accidents. In addition, in some metal smelting processes, a certain amount of slag will be added in order to improve the smelting effect, but most slag does not have conductive properties. When the part containing the slag leaks, the detection electrode of the prior art is difficult to identify and trigger an alarm, resulting in the failure of the warning. The utility model adopts the method of temperature monitoring of leaking furnace, avoids the technical problems of false alarm and missed alarm in the existing leaking furnace warning technology, and has the advantages of data recording, high monitoring accuracy, wide application range, convenient layout and low equipment cost. The following is a detailed description through specific embodiments.

[0044] See also Figure 1 , Figure 1 The structure diagram of the monitoring and alarm system of a medium frequency furnace provided by the utility model is shown. In one embodiment of the utility model, the monitoring and alarm system of the medium frequency furnace may include a furnace body 100, a thermal sensing module 200, and a circulating temperature measuring device 300. Among them, an induction coil 400 is wound around the outer wall of the furnace body 100. Specifically, the induction coil 400 is a spiral structure wrapped around the outer wall of the furnace body 100, which can be a single-turn induction coil or a multi-turn induction coil. The induction coil 400 can generate a uniform induced current in the furnace body 100 to achieve heating and melting of the internal metal material. The number of thermal sensing modules 200 can be multiple, and can be respectively arranged between different turns of the induction coil 400. The circulating temperature measuring device 300 can be electrically connected to each thermal sensing module 200. In this embodiment, when the circulating temperature measuring device 300 detects that the temperature of any thermal sensing module 200 exceeds the threshold, the circulating temperature measuring device 300 will execute an alarm to prompt the staff that a furnace leak may occur.

[0045] See also Figure 1 In one embodiment of the utility model, the furnace body 100 serves as a barrier between the interior of the medium frequency furnace and the external environment, which can effectively isolate the heat exchange between the high-temperature furnace and the outside world, reduce heat loss, and maintain the high temperature environment in the furnace. The center of the furnace body 100 can hold high-temperature molten metal. In this embodiment, the furnace body 100 may include an insulating layer 110 and a crucible 120. Among them, the insulating layer 110 is a furnace lining, and a accommodating cavity can be formed at its center. According to the type of material used, the insulating layer 110 can be divided into an acidic lining, an alkaline lining, and a neutral lining, etc. The crucible 120 can be arranged in the accommodating cavity formed by the insulating layer 110. The crucible 120 can be used to hold metal materials.

[0046] See also Figure 1 In one embodiment of the utility model, the induction coil 400 can be wound into a multi-turn coil in a spiral shape by a rectangular copper tube, and the surface is sprayed with high-strength insulating paint and wrapped with insulating tape. The turns of the induction coil 400 are also filled with refractory cement 500, and water cooling rings can be provided above and below the induction coil 400. The thermal sensing module 200 can be buried in the refractory cement 500. The service life of the refractory cement 500 is more than 2 years, which is a consumable material that is placed once and used for a long time. Therefore, the thermal sensing module 200 is set in the refractory cement 500 for repeated use, reducing maintenance costs. In some embodiments, the monitoring and alarm system of the medium frequency furnace also includes a yoke 600. The yoke 600 is set on the outside of the induction coil 400. The yoke 600 can be stacked with high-quality silicon steel sheets and distributed on the periphery of the induction coil 400 to play the role of a supporting skeleton. At the same time, the yoke 600 also plays the role of binding the external leakage magnetic flux of the induction coil 400 to prevent the metal components from heating up.

[0047] See also Figure 1 In one embodiment of the utility model, the monitoring and alarm system of the medium frequency furnace further includes a plurality of bottom sensor modules 700. The bottom sensor module 700 can be arranged at the bottom of the furnace body 100. It can be used to monitor whether there is leakage at the bottom of the furnace body 100. Specifically, the bottom sensor module 700 can be buried at the bottom position of the thermal insulation layer 110.

[0048] See also Figure 1 In one embodiment of the utility model, the circulating temperature measuring device 300 may include a controller 310 and an alarm 320. The controller 310 is electrically connected to each thermal sensing module 200 and each bottom sensing module 700. The controller 310 can record the temperature curves of the thermal sensing module 200 and the bottom sensing module 700. When an accident occurs, the specific cause of the accident can be determined based on the historical temperature curve. The alarm 320 can be electrically connected to the controller 310, and it can perform at least one alarm mode such as sound and light. In this embodiment, when the controller 310 detects that the temperature of any thermal sensing module 200 and / or any bottom sensing module 700 exceeds the threshold range, the alarm 320 will be controlled to alarm.

[0049] See also Figure 1 In one embodiment of the utility model, the thermal sensing module 200 may be a K-type thermocouple, that is, a nickel-chromium-nickel-silicon thermocouple, and its measurement range may be between -200°C and +1200°C. K-type thermocouples have the advantages of low cost, good stability, fast response speed, and a wide temperature measurement range, and are widely used in metallurgy, chemical industry, machinery and other fields. In this embodiment, the thermal sensing module 200 specifically adopts a double-core K-type thermocouple with a diameter of 0.5mm. Furthermore, since the thermal sensing module 200 is placed inward along the outer side of the induction coil 400, an insulating tube is provided on the outer side of the thermal sensing module 200 to ensure safe operation. The insulating tube may be a quartz ceramic tube, for example, a quartz ceramic tube with a diameter of 6mm and a wall thickness of 2mm. The insulating tube can insulate and isolate the thermal sensing module 200 from the induction coil 400. The thermal sensing module 200 and the circulating temperature measuring device 300 can be connected by a quick connector to facilitate maintenance and replacement.

[0050] See also Figure 2 , Figure 2The diagram shows a curve 800 showing the relationship between the temperature of the thermal sensing module 200 and the thickness of the furnace body 100 in one embodiment of the utility model. In one embodiment of the utility model, the temperature data of the thermal sensing module 200 can directly reflect the specific situation of the medium frequency furnace. As shown in the relationship curve 800, the ordinate is the temperature data of the thermal sensing module 200, and the abscissa is the thickness data of the medium frequency furnace body 100. When the thickness of the refractory material of the furnace body 100 is 130 mm and the temperature of the liquid in the furnace is 1500°C, the temperature at the refractory mortar 500 will be around 120°C. In this embodiment, when the furnace body 100 is eroded and thinned due to long-term use, the temperature measured by the thermal sensing module 200 shows a slow upward trend. When the furnace leaks during the smelting of non-conductive alloy metals, non-metals, and artificial slag making, the temperature measured by the thermal sensing module 200 will rise sharply. Therefore, monitoring the temperature curve of the thermal sensing module 200 can determine the type of accident and provide a reference for subsequent processing. Furthermore, the thickness of the furnace body 100 can be determined according to the temperature rise trend, and a timely warning can be issued.

[0051] See also Figure 1 In one embodiment of the utility model, the distribution of the thermal sensing module 200 and the bottom sensing module 700 is arranged according to the experience of the previous corrosion thinning position of the furnace body 100. Usually, after the furnace leaks, the liquid will pass through the semi-sintered layer and the dispersion layer to reach the position of the refractory cement 500, and the area will continue to increase during the penetration process. When it reaches the refractory cement 500, it can usually be guaranteed not to penetrate for 2 hours at 1700 degrees Celsius. During this time, the liquid will continue to diffuse outward and cause the temperature of the cement in a large area to rise. Therefore, the layout of the thermocouples is 30 cm apart to meet the monitoring and early warning needs of various medium frequency furnaces. As the refractory material is thinned, the layout of the thermocouples can be gradually reduced. In this embodiment, multiple thermal sensing modules 200 are evenly distributed along the busbar direction of the furnace body 100. The spacing between two adjacent thermal sensing modules 200 is between 15 cm and 40 cm. In addition, in order to avoid interference from the induction coil 400, the spacing between the thermal sensing module 200 and the turns of the induction coil 400 on both sides can be set to be greater than or equal to 1 cm.

[0052] In one embodiment of the utility model, first, the staff sets the alarm threshold of the circulating temperature measuring device 300 when the furnace is opened. Then, the circulating temperature measuring device 300 performs continuous monitoring and records the temperature curve of each thermal sensing module 200 and the bottom sensing module 700. When the temperature of any thermal sensing module 200 and / or any bottom sensing module 700 exceeds the set threshold, the controller 310 turns on the alarm 320 switch to sound and light alarm. At this time, the staff first stops the furnace and cuts off the power. After arriving at the site, check the number of sensor modules for specific alarms, and then check the historical temperature curve of the sensor module. If the temperature curve is in a slow rising state and the temperature of the thermal sensing module 200 has reached the temperature value corresponding to the standard service life of the insulation layer 110, it can be determined that the insulation layer 110 can no longer be used and needs to be cast or replaced in time. If the temperature curve shows a sharp upward trend, the next step of analysis can be performed based on the temperature of the sensor module. The first step is to rule out the possibility that the sensor module is faulty; the second step is to confirm that the sensor module is fault-free, then you can approach the furnace body 100 for visual and olfactory inspection. In this embodiment, when the temperature of the thermocouple exceeds 400°C, the insulating paint applied to the outside of the induction coil 400 will have a burnt smell due to the influence of temperature heat transfer. At this time, a more obvious pungent smell can be smelled near the intermediate frequency furnace, which can further make an accurate judgment on the condition of the intermediate frequency furnace. Finally, after eliminating the alarm problem, the historical temperature data can be exported for further review analysis and summary.

[0053] The utility model also provides a medium frequency furnace, which may include the monitoring and alarm system of the medium frequency furnace described in any of the above embodiments.

[0054] In summary, the utility model proposes a monitoring alarm system for a medium frequency furnace and a medium frequency furnace, which has the advantages of data recording, high monitoring accuracy, wide application range, convenient layout and low equipment cost. The utility model adopts a temperature monitoring method, which can effectively avoid false alarms and missed alarms caused by water vapor during the firing process of the medium frequency furnace. Therefore, the utility model effectively overcomes various shortcomings in the prior art and has a high industrial utilization value.

[0055] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed in the present invention shall still be covered by the claims of the present invention.

[0056] Therefore, many modifications may be made to adapt a particular environment or material to the essential scope and spirit of the present invention. The present invention is not intended to be limited to the specific terms used in the following claims and / or the specific embodiments disclosed as the best mode for carrying out the present invention, but the present invention will include any and all embodiments and equivalents falling within the scope of the appended claims. Therefore, the scope of the present invention will be determined only by the appended claims.

Claims

1. A monitoring and alarm system for a medium frequency furnace, characterized in that: include: A furnace body, the outer wall of which is wound with an induction coil; A plurality of thermal sensing modules are arranged between different turns of the induction coil; as well as A circulating temperature measuring device electrically connected to each of the thermal sensing modules; When the circulating temperature measuring device detects that the temperature of any of the thermal sensing modules exceeds a threshold value, the circulating temperature measuring device generates an alarm.

2. The monitoring and alarm system for the medium frequency furnace according to claim 1 is characterized in that: The furnace body comprises: A heat-insulating layer, a receiving cavity is formed at a center thereof; and A crucible is arranged in the containing cavity, and the crucible is used to contain metal materials.

3. The monitoring and alarm system for the medium frequency furnace according to claim 2 is characterized in that: The monitoring and alarm system of the medium frequency furnace also includes a plurality of bottom sensor modules, wherein the bottom sensor modules are buried at the bottom of the thermal insulation layer, and the bottom sensor modules are electrically connected to the circulating temperature measuring device.

4. The monitoring and alarm system for the medium frequency furnace according to claim 3 is characterized in that: The circulating temperature measuring device comprises: a controller, electrically connected to the thermal sensing module and the bottom sensing module, for recording historical temperature curves of the thermal sensing module and the bottom sensing module; and an alarm, electrically connected to the controller; When the controller detects that the temperature of any one of the thermal sensing modules and / or any one of the bottom sensing modules exceeds a threshold value, the controller activates the alarm.

5. The monitoring and alarm system for the medium frequency furnace according to claim 1 is characterized in that: The monitoring and alarm system of the intermediate frequency furnace also includes: Refractory cement, the refractory cement is filled between the turns of the induction coil; and The magnetic yoke is arranged on the outer side of the induction coil.

6. The monitoring and alarm system for the medium frequency furnace according to claim 5 is characterized in that: The thermal sensing module comprises: a thermocouple, embedded in the refractory mortar; and The insulating tube is sleeved on the thermocouple.

7. The monitoring and alarm system for the medium frequency furnace according to claim 1 is characterized in that: The distance between the thermal sensing module and the turns of the induction coils on two adjacent sides is greater than or equal to 1 cm.

8. The monitoring and alarm system for the medium frequency furnace according to claim 1 is characterized in that: The plurality of thermal sensing modules are evenly distributed along the busbar direction of the furnace body.

9. The monitoring and alarm system for the medium frequency furnace according to claim 8 is characterized in that: Along the busbar direction of the furnace body, the distance between two adjacent thermal sensing modules is in the range of 15 cm to 40 cm.

10. A medium frequency furnace, characterized in that: A monitoring and alarm system for a medium frequency furnace comprising the system described in any one of claims 1 to 9.

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