KR102219105B1 - Heating appliances for metal products - Google Patents

Abstract

The present invention relates to a heating device 10 for selectively heating one or more edges 12 of a metal product 11 with a desired thermal power by electromagnetic induction, said heating device comprising at least four polar extensions 18 ) And a magnetic core 13 having a through hole 14.

Description

Heating appliances for metal products

The present invention relates to a heating appliance for a metal product used in the steelmaking field, such as a casting plant, a rolling plant, a combination of these plants or other plants, where it is necessary to heat the metal product at different times each time. The heating device uses electromagnetic induction to heat the metal product.

By way of non-limiting example, the metal products in question include billets, blooms, wide plates, metal products, or semi-finished products having a square, rectangular, or polygonal cross section, which have edges. .

In the manufacture of metal products such as billets, blooms, or other similar metal products, it is known that the products are heated or maintained at a predefined temperature in order to obtain a metal product that is free from cracks and has the desired properties each time.

This can be achieved by using an appropriate induction heating device, depending on the magnetic field generated in each case, in particular by the electric current induced in the metal product, and due to the Joule effect it is possible to heat a part of the area of the metal product.

However, conventional induction heating devices are not capable of uniformly distributing heat power over the entire volume of the metal product, and cannot control the distribution of power from point to point or selectively.

In fact, after conventional heat treatment, the metal product has a significant lack of thermal uniformity corresponding to the edge, so the edge may be colder than other areas of the metal product.

These temperature differences can lead to surface cracks or other unwanted defects in the metal product.

Further, especially in a metal product obtained by continuous casting, when the positions of the edges of the metal product are different, such as a guide edge and an extra dose edge, the resulting metal product is different for a specific edge and suffers from a lack of thermal uniformity.

In this regard, it is clearly necessary to have at least all edges in the same thermal conditions, but due to specific process requirements, they must be heated differently at all points.

The heating can be carried out either by the casting step itself or downstream.

Induction heating devices are known which are configured to heat two opposite edges at a time or have two or more ferromagnetic cores each provided with two polar extensions.

Among them, the solution presented in patent document US 5.412.183 provides a step of simultaneously heating the metal product in a stepped plane.

Furthermore, these known solutions cannot selectively differentiate the heating of individual edges, and also cannot differentiate the thermal power delivered to the individual edges as required in each case.

Accordingly, there is a need to make available a heating appliance that completes the prior art and overcomes one or more of the disadvantages of the state of the art.

It is an object of the present invention to provide an induction heating device that can in each case heat one or more edges of a metal product at different points, optionally in a desired manner, thereby ensuring a uniform result.

Another object of the present invention is to provide an induction heating device capable of uniform heat distribution over all edges and differentiate the lead power delivered to them.

Another object of the present invention is to provide a heating device capable of simultaneously heat-treating one or more edges in connection with the heat treatment required in each case.

Another object of the present invention is to provide an induction heating device capable of heating specific areas and limited areas of metal products having various cross-sections, and at the same time maintaining excellent performance in required or desired heat power transfer.

Applicants devised, tested and implemented the present invention that overcomes the shortcomings of the prior art and obtains the above objects and advantages.

The invention is described and characterized in the independent claims, and the dependent claims describe other features of the invention or variations on the main invention.

According to the above object, the present invention is a heating device capable of heating one or more edges of a metal product with desired thermal power and selectively by electromagnetic induction, the heating device comprising a magnetic core having a through hole and a periphery of the through hole. It includes at least four polar extensions arranged at the same angle.

According to an aspect of the present invention, the polarity extensions lie on the same plane and are connected to each other by a connection, each polarity extension at least defining the polarity, frequency, and power delivered by the polarity extension in each case. Capable of having a corresponding electric coil connected to a power source.

Such a configuration, with a desirable and appropriately differentiated power, has four or more edges, for example billets, blooms, wide plates, metal articles, or semi-finished products with a square or rectangular cross section, or possible metal or mechanical artifacts. It makes it possible to use an induction heating appliance that selectively heats one or more edges of a metal product.

According to a possible embodiment, the polarity extension is selectively movable with respect to the through hole; Advantageously, but not limited to, the mobility of the polar extension is orthogonal or substantially orthogonal to the axis of passage through which the metal product passes.

The mobility of the polar extensions makes it possible to adjust and optimize the distance of the individual polar extensions with respect to the surface of the metal product in order to adjust the passage space of the through-holes for a specific cross section of the metal product to be treated.

In this way, high heating efficiency and safety can be obtained, even if the walls of the metal product on the one hand are not straight and not orthogonal to each other on the other hand.

According to a possible embodiment, the magnetic core includes one or more magnetic sectors sandwiched between the cooling plates, each magnetic sector including a desired plurality of magnetic sheets.

According to a possible variant, the magnetic coil is cooled by means of a cooling pipe through which the cooling liquid passes.

Included in this specification.

Features of the invention will become apparent from the following detailed description of some embodiments, which is provided as a non-limiting example with reference to the accompanying drawings.
1 is a perspective view of a heating device according to the present invention.
2 is a cross-sectional view of a heating device according to the present invention.
3 to 6 are four cross-sectional views schematically showing four configurations in use of the heating appliance according to the present invention.
7 to 9 are three cross-sectional views showing three configurations of possible embodiments of a heating appliance.
10 is a cross-sectional view of a modified embodiment of a heating device.
11 is a cross-sectional view of a modified embodiment of a heating device in one configuration in use.
12 and 13 are two cross-sectional views of two alternative embodiments of a heating appliance.
For ease of understanding, the same reference numbers are used to identify the same elements in the drawings as possible. Features and elements of one embodiment may be conveniently integrated into other embodiments without further explanation.

The embodiments described with reference to the drawings relate to a heating device 10 for a metal product 11.

The metal product 11 is a semi-finished product or metal product such as a billet or bloom, or a semi-finished product or molten metal product of square, rectangular or polygonal cross-section with one or more edges 12. it means.

According to the invention, the heating appliance 10 comprises a magnetic core 13 having a through hole 14 through which a metal product 11 is passed.

The magnetic core 13 may comprise a plurality of magnetic sheets 15 which are overlaid or clamped to form a single body or a whole composed of a plurality of magnetic sectors 16 in a known manner.

The magnetic sheet 15 may be, for example, a ferromagnetic material such as iron, nickel, cobalt, alloys thereof or other suitable materials.

The magnetic core 13 may be partially or wholly realized from one or more magneto-dielectirc compact materials that are not in the form of a sheet.

For example, the magnetic-electric compact material may include ferromagnetic metal powder contained in an insulating matrix.

According to a possible embodiment, the magnetic core 13 comprises one or more magnetic sectors 16, between the magnetic sectors there is a cooling plate 17, each magnetic sector 16 having a desired plurality of magnetic sheets ( 15).

The cooling plate 17 may be of an active or passive cooling type, and may also be configured to screen the heating device 10.

The magnetic core 13 has at least four polar extensions 18 arranged at the same angle along the periphery of the through hole 14.

In one embodiment, the polarity extension 18 extends the entire length of the magnetic core 13, so that when the heating device 10 functions, the polarity extension passes through the through hole 14 and passes through the metal product 11 ) Can be heated the entire length part.

According to one possible embodiment, when the through hole 14 is substantially square, possibly having a rounded edge, the polar extension 18 is disposed on the sides of the square defined by the perimeter of the through hole 14 And faces the inside of the through hole 14.

For each polarity extension 18, an upper end and a lower end may be defined. The polarity extension 18 is configured to act between the top and bottom.

The extended action of the polar extension 18 makes it possible to heat one or more edges 12 along the longitudinal direction of the metal product 11.

According to the invention, the polar extensions 18 are located in the same plane. The plane is defined as the plane on which all the tops and bottoms of the polar extension 18 lie.

According to an aspect of the present invention, the polarity extensions 18 are connected to each other by a connection 19 which is a part of the magnetic core 13.

The term “connected” refers to both polarized extensions 18 continuously connected to each other with connection 19, or polarized extensions 18 connected functionally with connection 19. That is, even if there is a minimum air gap, the magnetic magnetic flow line 22 can circulate between them.

According to possible embodiments, the connection portion 19 and the polar extensions 18 are two or more bodies and are structurally or functionally connected to each other to obtain a continuous magnetic flow.

Each polarity extension 18 is in each case an independent power source 21 capable of defining the polarity of each polarity extension 18 (refer to the direction of the magnetic flow line 22) and possible specific supply power. It has a corresponding electric coil 20 connected to.

According to a possible embodiment, the polarity extension part 18 and the connection part 19 may constitute the magnetic core 13 as a single body, or may consist of several bodies structurally or functionally connected to each other to obtain a continuous magnetic flow. I can.

This configuration, in which the continuity is not interrupted in the magnetic connection between the polarity extension 18 and the connection 19, allows the magnetic flow line 22 to be closed through the connection 19 to minimize energy loss. .

This causes the magnetic flow 22 generated by one polar extension 18 to be closed at one or both polar extensions 18 adjacent to it.

According to a possible embodiment, each of the electric coils 20 comprises an electric cable 23 connected to a power source 21, the electric cable 23 forming a reel having one or more spirals. It is wound around one polarity extension 18 for this purpose.

The electrical coils 20, correlated with the frequency and power range, may all be the same, or may differ depending on the requirements and details for each point in relation to the metal product to be treated.

According to a modified example, the electric coil 20 may be replaced, or may be manufactured to be replaceable.

In the attached drawing, the coil is characterized according to the direction of the current: “” represents the input current and “@” represents the output current.

According to a possible embodiment, the electric cable 23 may be implemented in a tubular shape with a conductive material such as a material having a high electric conductivity such as copper, and the electric cable 23 is cooled with a cooling liquid passing through it.

According to a possible embodiment, in order to slow the deterioration of the electrical cables 23, they can be located inside each cooling pipe 24 through which the cooling liquid passes.

The cooling pipe 24, which may have shapes connected with free space around the polarity extension 18, is provided by a power outlet 24a connected to one or more power sources, for example treated or untreated water, or oil. , Or a cooling fluid such as another fluid performing temperature may be supplied.

Referring to Figures 3-6, four possible use configurations are shown, in which a magnetic field and a corresponding magnetic flow line 22 are created that selectively activate one or more electric coils. Also, the activation may relate to the delivered power.

Depending on the direction, intensity, frequency of the current, and the electric coil 20 through which the current passes, each current is induced in correspondence with the metal product 11, in particular the edge 12 of the metal product.

The induced current heats each region 25 in each case and point by point, due to the Joule effect, around the edge 12. More specifically, in the drawings, reference numeral 25 denotes the area of the edge to be heated, and the varying size of the dotted circle is due to the large or small power transmitted by the corresponding polarity extension 18 affecting the specific area. Shows the large or small area affected.

The shape and size of the polarity extension 18 is configured to generate a magnetic field that traverses in the traveling direction of the metal product 11 in relation to the shape of the metal product 11.

In one configuration, the polarity extension 18 may have surfaces facing toward the through hole 14 of the magnetic core 13 and through which the magnetic flow lines 22 enter/exit substantially in parallel in pairs.

According to one variant, the one or more polar extensions 18 are shaped according to the physical shape of the metal product 11 to be treated.

According to a possible non-limiting embodiment, the surfaces of the one or more polar extensions 18 may be formed as wedges, with a parabolic shape or a concave or convex hyperbolic shape, with an inclined edge.

These configurations increase the power transfer efficiency from the polarity extension 18 to the metal product 11 to effectively direct magnetic flow toward the metal product 11.

According to a possible embodiment, the at least one polar extension 18 may include a replaceable portion that is raised as a shaped surface according to the metal product to be treated, and the shaped surface is, when in use, toward the through hole 14 Heading.

According to a possible variant, at least one of the polar extensions is configured in a separate manner according to the profile of the metal product 11. In other words, according to a possible modification, one or more specific polarity extensions 180 may have a surface facing toward the side surface group of the metal product 11 having a shape matching the side surface.

According to another variant, individualization is achieved in each case through specific additions to the polar extension 18 itself, paying attention to the functional continuity.

For example, a specific additional portion may be a portion of the metal product 11 to be treated or a polar extension 18 specifically adapted to the heat treatment to be performed.

According to another variant, one or more polar extensions 18 may be replaced both for maintenance reasons and for specific reasons for individualization.

Regarding the exemplary configurations, FIG. 3 shows a case in which power is supplied to only one electric coil 20, which induces a current near two adjacent edges 12.

4 shows a case where power is supplied to two adjacent electric coils 20, and the directions of currents are opposite to each other. In other words, the induced current makes it possible to heat one edge 12 with a greater intensity than two adjacent edges 12.

5 shows a case in which power is supplied to all the current coils 20, and each current coil is supplied with a current having a direction opposite to the current passing through the current coil 20 adjacent thereto. That is, the induced current makes it possible to heat all four edges 12.

6 shows a case where power is supplied to all the current coils 20, and each current coil does not have a current in the opposite direction to the current passing through one of the adjacent current coils 20, but the other adjacent current coils It has the same direction as the current passing through (20). In this case, the induced current makes it possible to heat the two opposite edges 12.

According to a possible embodiment, the polarity extension 18 may selectively move with respect to the through hole 14.

According to a possible embodiment, the polarity extension 18 may be selectively moved perpendicular to the through hole 14 as shown in FIGS. 7 to 11.

According to a possible embodiment, the polar extension 18 is a corresponding independent actuator 26, possibly linear, in order to adjust the distance between the surface of the metal product 11 and the specific polar extension 18 Can be moved by

This configuration can optimize the position of the polar extension 18 to heat the desired edge 12 to the desired depth, while at the same time ensuring high performance of heat transfer.

In Fig. 10 it is useful and necessary for the electric coil 20 to be as close as possible to the surface on which the magnetic flow line 22 is to operate is shown as an example.

In this case, the movable polar extension 18 also has a seating for the electric coil 22.

According to this embodiment, in order to induce current only at the edge 12 to be heated, two polarity extensions 18 are arranged near a specific edge 12 and power is supplied to one of the two electric coils 20. It is possible (see Fig. 11).

Modifications and/or additions of components may be made to the heating device 10 described above without departing from the field and scope of the present invention.

For example, according to a possible variant, a receiving body 27 can be provided in the through hole, which can accommodate the metal product 11 while passing into the heating device 10.

The receiving body 27 may be configured to guide the metal product along a defined path.

The receiving body 27 may be made of a shielding material that can pass through the magnetic flow line 22 but does not dissipate heat generated from the metal product 11.

The receiving body 27 can also function as a physical barrier to ensure that the polar extension 18 does not come into contact with the metal product 11.

In addition, although the present invention has been described with reference to some specific embodiments, a person skilled in the art can achieve many other equivalent types of heating devices of heating device 10, which are within the scope of the claims and the protection defined accordingly. This is self-explanatory.

Claims (10)

A heating device capable of selectively heating one or more edges 12 of a metal product 11 with a desired thermal power by electromagnetic induction,
The heating device comprises a magnetic core 13 having a through hole 14 and at least four polar extensions 18 disposed at the same angle along the periphery of the through hole,
The polarity extensions 18 lie on the same plane and are connected to each other by a connection 19,
Each polarity extension 18 is a heating appliance having a corresponding electric coil 20 connected to a power source 21 capable of at least defining the polarity, frequency, and power delivered by the polarity extension 18. . The method of claim 1,
The polarity extension portion 18 and the connection portion 19 are a heating device constituting a magnetic core as a single body. The method of claim 1,
The polarity extension 18 and the connection 19 are two or more bodies, and are structurally or functionally connected to each other in order to obtain a continuous magnetic flow. The method of claim 3,
The polarity extension 18 is a heating device selectively movable with respect to the through hole 14. The method of claim 4,
The polarity extension 18 can be selectively moved vertically relative to the through hole 14 by means of a corresponding independent actuator 26. The method according to any one of claims 3 to 5,
The polarity extension 18 is a movable heating device that can be optionally replaced. The method of claim 1,
At least one of the polar extensions 18 is configured in a separate manner according to the profile of the metal product 11. The method of claim 1,
The magnetic core 13 includes one or more magnetic sectors between the cooling plates 17, each magnetic sector 16 including a plurality of magnetic sheets 15. The method of claim 1,
Each electric coil 20 includes an electric cable 23 connected to a power source 21, the electric coil 20 being located in a separate cooling pipe 24 through which the cooling liquid passes. The method of claim 1,
Each electric coil 20 can be replaced with a heating appliance.

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