Furnace ramming method for intermediate frequency furnace

Abstract

The invention relates to a furnace ramming method for an intermediate frequency furnace. The furnace ramming method comprises the following steps that S1, the inner side wall of a furnace cavity is cleaned; s2, a ramming furnace core of a cylindrical structure is vertically installed in the cleaned furnace cavity, and a ramming furnace cavity is formed between the peripheral side face of the ramming furnace core and the inner side wall of the furnace cavity; s3, a layer of refractory furnace charge is loaded into the furnace ramming cavity, and then a worker stands above the furnace cavity to perform furnace ramming; after one layer of furnace ramming is finished, the refractory furnace charge is reloaded, next layer of furnace ramming is carried out, and layer-by-layer furnace ramming from bottom to top is achieved through the circulation; and S4, after furnace ramming in the whole furnace ramming cavity is finished, the furnace ramming furnace core is taken out of the furnace cavity. The design is reasonable, the furnace ramming furnace core is arranged in the furnace cavity through the furnace ramming head, the furnace ramming furnace core plays a supporting role, the wall thickness of the furnace lining can be conveniently controlled in the furnace ramming process, meanwhile, workers do not need to enter the furnace cavity in the furnace ramming process, and the operation convenience is improved.

Description

Technical Field

[0001] The invention relates to a method for beating a medium frequency furnace. Background Art

[0002] Medium frequency furnace (also called melting furnace or induction furnace) is an induction heating device that converts 50hz electrical frequency into 300-1000hz. It uses the principle of electromagnetic induction to heat the metal and other induction materials placed in its own furnace body. It is widely used for smelting and heating of metals, such as smelting pig iron, ordinary steel, stainless steel, tool steel, copper, aluminum, gold, silver and alloys.

[0003] During the operation of the medium frequency furnace, the molten metal will come into direct contact with the induction coil, causing the insulation layer on the surface of the coil to be destroyed, which in turn causes sparking. In addition, during the long-term use of the medium frequency furnace, the refractory material in the furnace will gradually become thinner, causing the working environment temperature of the coil to rise. Ordinary insulating paint cannot withstand high temperatures and is easily carbonized. These problems will cause damage to the coil and affect the normal operation of the medium frequency furnace. For this reason, the medium frequency furnace needs to be beaten after working for a certain period of time. However, the traditional method of beating a medium frequency furnace is to manually build a certain thickness of refractory material directly inside the furnace cavity and on the surrounding side of the furnace cavity to form a furnace lining. In this furnace beating method, due to the lack of support inside the furnace cavity, the wall thickness of the furnace lining is difficult to control during the furnace beating process, and uneven wall thickness is prone to occur. There is also the problem of inconvenient construction in the furnace cavity. Therefore, it is necessary to make improvements to this technical problem. Summary of the invention

[0004] The present invention aims to improve the problems existing in the above-mentioned prior art, that is, the technical problem to be solved by the present invention is to provide a medium frequency furnace firing method with reasonable design, improved construction convenience and convenient control of the wall thickness of the furnace lining.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: a method for firing a medium frequency furnace, comprising the following steps: Step S1: cleaning the inner wall of the furnace chamber; Step S2: vertically inserting a furnace core of a cylindrical structure into the cleaned furnace cavity, so that a furnace cavity is formed between the outer peripheral side of the furnace core and the inner side wall of the furnace cavity; Step S3: a layer of refractory charge is loaded into the furnace chamber, and then a person stands on the furnace chamber to fire the furnace; after the firing of one layer is completed, the refractory charge is reloaded and the next layer is fired, and the firing is realized layer by layer from bottom to top in this cycle; Step S4: After the furnace is fired in the entire furnace cavity, the furnace core is taken out from the furnace cavity.

[0006] Furthermore, in step S2 and step S43, the furnace core is hoisted by a crane.

[0007] Further, the furnace core of the furnace building includes a cylindrical steel mold with a cavity inside. A lifting ring is fixedly arranged at the open top of the steel mold, and the outer circumferential side of the steel mold is a smooth surface.

[0008] Further, a plurality of reinforcing frames are arranged in the inner cavity of the steel film. The plurality of reinforcing frames are evenly spaced from top to bottom along the axial direction of the steel mold, and the reinforcing frames are in a cross shape.

[0009] Further, in step S1, after the inner side wall of the furnace cavity is cleaned, red mud is applied to the inner circumferential surface of the induction coil, and the red mud is filled between adjacent turns of the induction coil.

[0010] Further, after the furnace core of the furnace building is taken out of the furnace cavity, a circle of refractory furnace material is filled above the induction coil. The refractory furnace material is arranged in a ring on the outer periphery of the upper end of the furnace lining, and then the furnace cover is covered.

[0011] Further, the furnace cover includes an annular furnace cover end plate and a cylindrical furnace cover body coaxially arranged at the inner end of the furnace cover end plate and protruding upward. A vertical through hole corresponding to the position of the furnace cavity of the intermediate frequency furnace is opened in the middle of the top of the furnace cover body. A connecting piece for connecting with the refractory furnace material on the intermediate frequency furnace is arranged on the lower surface of the top of the furnace cover body and is arranged in a ring on the outer periphery of the vertical through hole.

[0012] Further, the connecting piece includes a first connecting piece and a second connecting piece arranged coaxially and inside and outside. The first connecting piece includes a plurality of first connecting hanging rods evenly distributed in a circle around the axis of the vertical through hole. The first connecting hanging rods are in an inverted "dry" shape and are arranged along the tangent direction of the circumferential side of the vertical through hole. The second connecting piece includes a plurality of second connecting hanging rods evenly distributed in a circle around the axis of the vertical through hole. The second connecting hanging rods are also in an inverted "dry" shape, and the second connecting hanging rods are parallel to the radial direction of the vertical through hole. The first connecting hanging rods and the second connecting hanging rods are used to hang the refractory furnace material arranged in a ring above the upper end of the intermediate frequency furnace on the induction coil.

[0013] Further, a plurality of first reinforcing rods are arranged in a ring on the outer side of the vertical through hole inside the top end of the furnace cover body. The first reinforcing rods are arranged vertically and the lower ends extend out of the furnace cover body. The positions of the plurality of first reinforcing rods correspond to the positions of the plurality of first connecting hanging rods, and the first connecting hanging rods are welded and fixed to the bottom of the first reinforcing rods. An annular reinforcing rod is arranged in a ring on the outer side of the plurality of first reinforcing rods inside the top end of the furnace cover body. A plurality of second reinforcing rods are vertically arranged and the lower ends extend out of the furnace cover body are fixed on the inner circumferential surface of the annular reinforcing rod. The positions of the plurality of second reinforcing rods correspond to the positions of the plurality of second connecting hanging rods, and the second connecting hanging rods are welded and fixed to the bottom of the second reinforcing rods.

[0014] Compared with the prior art, the present invention has the following effects: the present invention is reasonably designed, and the furnace core is loaded into the furnace cavity through the furnace making machine, and the furnace core is used to play a supporting role, so that the wall thickness of the furnace lining can be controlled during the furnace making process. At the same time, there is no need for manual entry into the furnace cavity during the furnace making process, which improves the convenience of operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the structure of the intermediate frequency furnace body before firing according to an embodiment of the present invention; Figure 2 yes Figure 1 A schematic diagram of the structure of a furnace core loaded in the furnace; Figure 3 yes Figure 2 Schematic diagram of the structure after the middle furnace is completed and the furnace core is taken out; Figure 4 yes Figure 3 Schematic diagram of the structure after the middle cover is equipped with the upper furnace cover; Figure 5 It is a schematic diagram of the main cross-sectional structure of the furnace core in an embodiment of the present invention; Figure 6 1 is a schematic diagram of a top view of a furnace core in an embodiment of the present invention; Figure 7 is a schematic diagram of the main cross-sectional structure of a furnace cover in an embodiment of the present invention; Figure 8 1 is a bottom view of the structure of the furnace cover in an embodiment of the present invention; Fig. 9 yes Figure 8 The structural diagram of the connecting parts is omitted; Fig.10 1 is a schematic diagram of a top view of a furnace cover according to an embodiment of the present invention; Fig.11 It is a schematic diagram of the structure of the first and second connecting rods of the furnace cover in an embodiment of the present invention.

[0016] In the figure: 1-furnace cover; 2-furnace cover end plate; 3-furnace cover body; 4-furnace cavity; 5-vertical through hole; 6-first connecting rod; 7-second connecting rod; 8-electromagnetic coil; 9-refractory charge; 10-furnace lining; 11-first reinforcing rod; 12-annular reinforcing rod; 13-second reinforcing rod; 14-iron outlet chute; 15-insulation layer; 16-furnace body; 17-furnace core; 18-steel mold; 19-reinforcement frame; 20-red mud; 21-furnace cavity; 22-lifting ring;. DETAILED DESCRIPTION

[0017] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0018] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0019] like Figures 1 to 4 As shown, the present invention provides a method for beating a medium frequency furnace, and the method comprises the following steps: Step S1: cleaning the inner wall of the furnace chamber 4 to remove the residual furnace charge on the surrounding wall of the furnace chamber; Step S2: Refractory furnace materials are then laid at the bottom of the furnace cavity 4 to form the bottom of the furnace lining, and then the furnace core 17 of the cylindrical structure is vertically installed into the cleaned furnace cavity 4, and the furnace core 17 is kept at the center of the furnace cavity 4, and a circular furnace cavity 21 is formed between the outer peripheral side of the furnace core 17 and the inner wall of the furnace cavity 4; Step S3: a layer of refractory furnace charge 9 is loaded into the furnace chamber 21, and then a person stands on the furnace chamber 4 (the top of the furnace body) to fire the furnace; after the firing of one layer is completed, the refractory furnace charge is reloaded and the next layer of firing is carried out, and the firing is realized layer by layer from bottom to top in this cycle; Step S4: After the furnace is fired in the entire furnace chamber, the furnace core 17 is taken out from the furnace chamber.

[0020] In this embodiment, in step S2 and step S43, the furnace core 17 is hoisted by a crane.

[0021] In this embodiment, the furnace core 17 includes a cylindrical steel mold 18 with a cavity inside. The top of the steel mold 18 is open and fixed with a lifting ring 22, which is convenient for hooking by a crane. The outer circumference of the steel mold 18 is a smooth surface.

[0022] In this embodiment, in order to improve the structural strength of the steel mold, the internal cavity of the steel membrane 18 is provided with a plurality of reinforcing frames 19, which are evenly spaced from top to bottom along the axial direction of the steel mold 18, and the reinforcing frames 19 are cross-shaped.

[0023] In this embodiment, in step S1, after cleaning the inner wall of the furnace chamber 4, red mud 20 is applied to the inner peripheral side of the induction coil 8, and the red mud 20 is filled between two adjacent coils of the induction coil 8. By applying red mud, the wire ignition and imaging during the operation of the induction coil can be effectively avoided.

[0024] In this embodiment, after the furnace core 17 is taken out of the furnace cavity 4, a ring of refractory furnace charge 9 is filled above the induction coil 8. The refractory furnace charge 9 is arranged around the outer periphery of the upper end of the furnace lining 10, and then the furnace cover 1 is covered to complete the entire furnace building process in sequence.

[0025] In this embodiment, as Figure 7-11 shown, the furnace cover 1 includes an annular furnace cover end plate 2 and a cylindrical furnace cover body 3 coaxially arranged at the inner end of the furnace cover end plate 2 and protruding upward. The furnace cover end plate 2 and the furnace cover body 3 form a stepped shaft shape with a larger lower end and a smaller upper end. A vertical through hole 5 corresponding to the position of the furnace cavity 4 of the intermediate frequency furnace is provided in the middle of the top of the furnace cover body 3. A connecting member for connecting with the refractory furnace charge on the intermediate frequency furnace is arranged on the lower surface of the top of the furnace cover body 3 around the outer periphery of the vertical through hole 5.

[0026] In this embodiment, specifically, the connecting member includes a first connecting member and a second connecting member arranged coaxially and distributed inside and outside. The first connecting member includes a plurality of first connecting hanging rods 6 evenly distributed in a circumferential manner around the axis of the vertical through hole 5. The first connecting hanging rods 6 are in an inverted "dry" shape and are arranged along the tangent direction of the circumference of the vertical through hole 5. The second connecting member includes a plurality of second connecting hanging rods 7 evenly distributed in a circumferential manner around the axis of the vertical through hole 5. The second connecting hanging rods 7 are also in an inverted "dry" shape and are parallel to the radial direction of the vertical through hole 5. The first connecting hanging rods 6 and the second connecting hanging rods 7 are used to hang the refractory furnace charge 9 arranged in a ring above the induction coil 8 at the upper end of the intermediate frequency furnace.

[0027] During use, the furnace cover structure 1 is covered on the furnace body of the intermediate frequency furnace. The furnace cover end plate 2 is in contact with the top surface of the furnace body. The vertical through hole 5 of the furnace cover body 3 corresponds to the position of the furnace cavity 10 of the intermediate frequency furnace. The refractory furnace charge 9 arranged in a ring above the induction coil 8 at the upper end of the intermediate frequency furnace is hung on the first connecting hanging rods 6 and the second connecting hanging rods 7 to realize the connection between the furnace cover and the furnace body of the intermediate frequency furnace. The furnace cover end plate and the furnace cover body form a stepped shaft shape, which improves the structural strength of the furnace cover of this application. And a connecting member is arranged on the inner side of the furnace cover body. When the furnace cover is covered on the intermediate frequency furnace, the connecting member is connected with the refractory furnace charge on the intermediate frequency furnace, which improves the connection structural strength between the furnace cover and the intermediate frequency furnace and effectively reduces the deformation of the furnace cover during work.

[0028] In this embodiment, in order to improve the structural strength of the furnace cover itself, a plurality of first reinforcing rods 11 arranged around the outside of the vertical through hole 5 are arranged inside the top of the furnace cover body 3, and the first reinforcing rods 11 are arranged vertically and the lower ends extend out of the furnace cover body 3; an annular reinforcing rod 12 arranged around the outside of the plurality of first reinforcing rods 11 is arranged inside the top of the furnace cover body 3, and a plurality of second reinforcing rods 13 arranged vertically and the lower ends extend out of the furnace cover body 3 are fixed to the inner circumferential side of the annular reinforcing rod 12. The structural strength of the top of the furnace cover body is improved by the first reinforcing rods, the annular reinforcing rods and the second reinforcing rods, and deformation during use is reduced.

[0029] In this embodiment, the positions of the plurality of first reinforcing rods 11 correspond to the positions of the plurality of first connecting hanging rods 6 , and the first connecting hanging rods 6 are welded and fixed to the bottom of the first reinforcing rods 11 .

[0030] In this embodiment, the positions of the plurality of second reinforcing rods 12 correspond to the positions of the plurality of second connecting hanging rods 7 , and the second connecting hanging rods 12 are welded and fixed to the bottom of the second reinforcing rods 7 .

[0031] In this embodiment, the furnace cover body 3 and the furnace cover end plate 2 are integrally formed by sand casting, and the first reinforcing rod, the annular reinforcing rod and the second reinforcing rod are all pre-buried inside the furnace cover body during sand casting.

[0032] In this embodiment, an iron outlet groove 14 is arranged on the top of the furnace cover body 3. The iron outlet groove 14 is connected to the vertical through hole 5. The iron outlet groove is inclined to facilitate the output of molten iron.

[0033] If the present invention discloses or involves components or structures that are fixedly connected to each other, then, unless otherwise stated, the fixed connection can be understood as: a detachable fixed connection (for example, connection using bolts or screws), and can also be understood as: a non-detachable fixed connection (for example, riveting, welding). Of course, the mutual fixed connection can also be replaced by an integrated structure (for example, manufactured by one-piece molding using a casting process) (except when it is obviously impossible to use an one-piece molding process).

[0034] In addition, unless otherwise stated, the terms used to indicate positional relationships or shapes in any of the technical solutions disclosed in the present invention include states or shapes that are approximate, similar, or close to them.

[0035] Any component provided by the present invention may be assembled from a plurality of separate components, or may be a separate component manufactured by an integral forming process.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the present invention, which should be included in the scope of the technical solution for protection of the present invention.

Claims

1. A method for firing a medium frequency furnace, characterized in that: The steps include: Step S1: cleaning the inner wall of the furnace chamber; Step S2: vertically inserting a furnace core of a cylindrical structure into the cleaned furnace cavity, so that a furnace cavity is formed between the outer peripheral side of the furnace core and the inner side wall of the furnace cavity; Step S3: a layer of refractory charge is loaded into the furnace chamber, and then a person stands on the furnace chamber to fire the furnace; after the firing of one layer is completed, the refractory charge is reloaded and the next layer is fired, and the firing is realized layer by layer from bottom to top in this cycle; Step S4: After the furnace is fired in the entire furnace cavity, the furnace core is taken out from the furnace cavity.

2. A medium frequency furnace beating method according to claim 1, characterized in that: In step S2 and step S43, the furnace core is hoisted by a crane.

3. A medium frequency furnace beating method according to claim 1 or 2, characterized in that: The furnace core comprises a cylindrical steel mold with a cavity inside, a hanging ring is fixed on the open top of the steel mold, and the outer circumference side of the steel mold is a smooth surface.

4. A method for firing a medium frequency furnace according to claim 3, characterized in that: The inner cavity of the steel film is provided with a plurality of reinforcing frames, which are evenly spaced from top to bottom along the axis direction of the steel mold, and the reinforcing frames are in a cross shape.

5. A medium frequency furnace firing method according to claim 1, characterized in that: In step S1, after the inner wall of the furnace cavity is cleaned, red mud is applied to the inner peripheral side of the induction coil, and the red mud is filled between two adjacent turns of the induction coil.

6. A method for firing a medium frequency furnace according to claim 1, characterized in that: After the furnace core is taken out from the furnace cavity, a circle of refractory furnace charge is filled above the induction coil. The refractory furnace charge ring is arranged on the outer peripheral side of the upper end of the furnace lining, and then the furnace cover is covered.

7. A method for firing a medium frequency furnace according to claim 6, characterized in that: The furnace cover includes an annular furnace cover end plate, a cylindrical furnace cover body coaxially arranged at the inner end of the furnace cover end plate and protruding upward, a vertical through hole corresponding to the furnace chamber position of the medium frequency furnace is opened in the middle of the top of the furnace cover body, and a connecting piece is arranged on the lower surface of the top of the furnace cover body, which is arranged on the outer peripheral side of the vertical through hole and is used to connect with the refractory charge on the medium frequency furnace.

8. A method for firing a medium frequency furnace according to claim 7, characterized in that: The connecting member includes a first connecting member and a second connecting member that are coaxially arranged and distributed inside and outside. The first connecting member includes a plurality of first connecting rods that are evenly distributed around the axis of the vertical through hole in a circle, and the first connecting rods are in an inverted "stem" shape. The first connecting rods are arranged along the tangent direction of the circumference of the vertical through hole; the second connecting member includes a plurality of second connecting rods that are evenly distributed around the axis of the vertical through hole in a circle, and the second connecting rods are also in an inverted "stem" shape. The second connecting rods are parallel to the radial direction of the vertical through hole. The first connecting rod and the second connecting rod are convenient for hanging the refractory charge arranged on the upper end of the medium frequency furnace above the induction coil.

9. A method for firing a medium frequency furnace according to claim 8, characterized in that: A plurality of first reinforcing rods arranged around the outside of the vertical through holes are arranged inside the top end of the furnace cover body, the first reinforcing rods are arranged vertically and the lower ends extend out of the furnace cover body, the positions of the plurality of first reinforcing rods correspond to the positions of the plurality of first connecting hanging rods, and the first connecting hanging rods are welded and fixed to the bottom of the first reinforcing rods; an annular reinforcing rod arranged around the outside of the plurality of first reinforcing rods is arranged inside the top end of the furnace cover body, a plurality of second reinforcing rods arranged vertically and the lower ends extend out of the furnace cover body are fixed to the inner circumferential side surface of the annular reinforcing rod, the positions of the plurality of second reinforcing rods correspond to the positions of the plurality of second connecting hanging rods, and the second connecting hanging rods are welded and fixed to the bottom of the second reinforcing rods.

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