A rotary hearth furnace bottom outer ring frame integral pouring structure

Abstract

The utility model provides a kind of rotary hearth furnace bottom outer ring frame integral pouring structure, it is related to rotary hearth furnace technical field, including multiple pouring sections;First expansion joint is equipped between adjacent pouring section;Each pouring section includes wall body, furnace bottom matrix and angle bead plate;The angle bead plate includes first end body and second end body;The first end body is located on the surface of furnace bottom matrix;Second end body is located on the outer side of furnace bottom matrix;The wall body is located on furnace bottom matrix, and it is oppositely arranged with angle bead plate;The wall body, first end body and second end body form groove;Pouring material is injected in the groove;Multiple anchoring hooks are equipped on the first end body, to fix pouring material and pouring section.The utility model solves the problem that prefabricated brick is easy to crack, peel off and wear in prior art, significantly prolongs the service life of frame structure.

Description

Technical Field

[0001] This utility model relates to the field of rotary hearth furnace technology, and in particular to an integral casting structure for the outer ring frame of the rotary hearth furnace bottom. Background Technology

[0002] In the metallization pellet production process, green pellets are reduced at high temperatures in a rotary hearth furnace to form metallized pellets. The outer ring frame (also known as the baffle wall or edge brick) of the rotary hearth furnace body is subjected to high temperature, material friction, mechanical impact, and periodic rapid heating and cooling environments for a long time.

[0003] The general process of metallized pellet production is as follows: various iron-containing raw materials, such as iron concentrate, are mixed with suitable binders and additives to meet the requirements of subsequent molding and reduction. Then, the mixed materials are formed into green pellets with a certain strength and size using equipment such as a briquetting machine. Next, the green pellets are placed in a rotary hearth furnace for self-reduction at high temperature. In this process, coal gas is used as a reducing agent to reduce the iron oxides in the green pellets to metallic iron, forming metallized pellets. After reduction, the metallized pellets are cooled in a cylindrical cooling device to lower their temperature to a level suitable for subsequent processing. Since a small amount of pellet powder is generated during self-reduction and cylindrical cooling in the rotary hearth furnace, a finished product bucket elevator and a vibrating screen are currently used to separate the cooled pellets from the undersize powder. Qualified metallized pellets are sent to appropriate silos for further processing or storage, while the undersize powder is sent to appropriate silos for storage.

[0004] The outer ring frame bricks of the rotary hearth furnace body are subject to thermal expansion and contraction. During the production process, external factors may cause the frame bricks to loosen due to rapid heating and cooling. After the metallized pellets enter the rotary hearth furnace body, they are conveyed to the outside by the spiral feeder, which causes the frame bricks to break under stress. This results in the broken frame bricks entering the chute or water seal trough, causing problems such as material jamming or water seal trough scraper jamming.

[0005] Currently, most rotary hearth furnaces in China use precast irregular-shaped bricks to construct the outer ring frame. A layer of ceramic fiber blanket is laid at the bottom of the furnace, followed by a layer of lightweight castable refractory. The furnace is then leveled with refractory mortar, and precast bricks are laid on top of the refractory mortar. Lightweight castable refractory is then used to fix the precast bricks in place. However, this structure has the following significant drawbacks:

[0006] Poor thermal shock resistance: Precast blocks are prone to cracking or even peeling under drastic temperature fluctuations (rapid cooling and heating) in the furnace, leading to structural failure and shortened lifespan;

[0007] Insufficient wear resistance: Due to long-term friction and erosion from metallized pellets, the precast block material has limited wear resistance and is prone to wear and deformation, affecting the material blocking effect and furnace bottom sealing.

[0008] Installation and maintenance are inconvenient: the precast blocks are large and heavy, requiring precise alignment during installation, and replacement is time-consuming and labor-intensive, affecting production efficiency and equipment availability.

[0009] Structural stability issues: Due to thermal expansion and contraction and external forces (such as the action of a screw conveyor), precast bricks are prone to loosening and breakage. Broken bricks are easy to fall into the chute or water seal trough, causing equipment failures such as material jamming and scraper jamming, which affects continuous production.

[0010] In view of this, this utility model is proposed. Utility Model Content

[0011] The purpose of this utility model is to provide an integral cast-in-place structure for the outer ring frame of the rotary hearth furnace bottom, overcoming the problems of poor thermal shock resistance, insufficient wear resistance, difficulty in installation and replacement, and easy loosening and damage leading to material jamming in the existing precast irregular brick outer ring frame.

[0012] To achieve the above objectives, the present invention adopts the following technical solution:

[0013] This utility model provides an integral casting structure for the outer ring frame of the bottom of a rotary hearth furnace, comprising multiple casting sections 1;

[0014] A first expansion joint 4 is provided between adjacent pouring sections 1;

[0015] Each of the aforementioned casting sections 1 includes a wall 2, a furnace bottom base 5, and a corner guard 3;

[0016] The corner guard plate 3 includes a first end body 31 and a second end body 32; the first end body 31 is located on the surface of the furnace bottom base 5; the second end body 32 is located on the outer side of the furnace bottom base 5.

[0017] The wall 2 is located on the furnace bottom base 5 and is positioned opposite to the corner guard 3;

[0018] The wall 2, the first end body 31 and the second end body 32 form a groove; the groove is filled with castable 6; a plurality of anchor hooks 9 are provided on the first end body 31 to fix the castable 6 and the casting section 1.

[0019] Furthermore, based on the above technical solution, the first expansion joint 4 is provided with a PVC corrugated expansion joint plate;

[0020] The width of the first expansion joint 4 is 9-11 mm.

[0021] Furthermore, based on the above technical solution, the included angle 10 formed by the first end body 31 and the second end body 32 is greater than or equal to 90°.

[0022] Furthermore, based on the above technical solution, the first end body 31 is fixed to the furnace bottom base 5 by multiple bolts 12 and multiple first L-shaped fasteners 11;

[0023] The first L-shaped fastener 11 is located below the furnace bottom base 5, and the bolt 12 passes through the first end body 31, the furnace bottom base 5 and the first L-shaped fastener 11 to fix the three together.

[0024] Furthermore, based on the above technical solution, the first end body 31 is also provided with a support body 8, and an anchoring hook 9 is provided on the support body 8.

[0025] The anchor hook 9 is a Y-type anchor hook.

[0026] Furthermore, based on the above technical solution, a second L-shaped fastener 13 is provided on the furnace bottom base 5. One end of the second L-shaped fastener 13 is connected and fixed to the support body 8 by bolts 12, and the other end is connected and fixed to the furnace bottom base 5 by bolts 12 and the first L-shaped fastener 11.

[0027] Furthermore, based on the above technical solution, the spacing between the multiple anchoring hooks 9 is ≤200mm.

[0028] Furthermore, based on the above technical solution, a second expansion joint is provided between the inner side of the groove and the castable 6; a ceramic fiber blanket 7 is provided in the second expansion joint.

[0029] Furthermore, based on the above technical solution, the width of the second expansion joint is 24-26mm.

[0030] Furthermore, based on the above technical solution, the length of each of the casting sections 1 is ≤1.4m.

[0031] The integral casting structure for the outer ring of the rotary hearth furnace bottom provided by this utility model has at least the following beneficial effects:

[0032] 1. Significantly improved durability: The overall structure of the low-cement, high-strength castable has excellent thermal shock resistance, wear resistance, and mechanical strength, which fundamentally solves the problems of cracking, peeling, and wear of precast bricks, and significantly extends the life of the frame.

[0033] 2. Enhanced structural stability: The integral casting combined with Y-shaped anchor hooks ensures a tight and firm bond between the frame and the base, effectively resisting thermal and mechanical stresses (such as the force of the material discharge machine), greatly reducing the risk of loosening and breakage, and eliminating material jamming and scraper jamming caused by broken and falling frame bricks.

[0034] 3. Ensure production continuity: By improving the reliability and stability of the frame, unplanned shutdowns for maintenance due to frame damage are reduced, thereby increasing the operating rate of the rotary hearth furnace and the continuity of metallization pellet production.

[0035] 4. Precise thermal expansion management: The reasonable expansion joint design (first expansion joint, second expansion joint, etc.) effectively releases thermal stress, prevents the structure from cracking or deforming due to limited expansion, and ensures the stability of long-term operation. Attached Figure Description

[0036] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0037] Figure 1 A schematic diagram of the integral casting structure of the outer ring frame of the rotary hearth furnace bottom provided by this utility model;

[0038] Figure 2 This is a schematic diagram of the structure of the multiple casting sections provided by this utility model;

[0039] Figure label:

[0040] 1. Casting section; 2. Wall; 3. Corner guard; 31. First end body; 32. Second end body; 4. First expansion joint; 5. Furnace bottom base; 6. Castable refractory; 7. Ceramic fiber blanket; 8. Support body; 9. Anchor hook; 10. Angle; 11. First L-shaped fastener; 12. Bolt; 13. Second L-shaped fastener. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions in the embodiments of this utility model will be clearly and completely described below in conjunction with the embodiments of this utility model. Those skilled in the art should understand that the embodiments described are merely to help understand this utility model and should not be considered as specific limitations on this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model. Process parameters in the following embodiments that do not specify specific conditions are generally based on conventional conditions.

[0042] The endpoints and any values ​​of the ranges disclosed in this utility model are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this utility model.

[0043] According to a first aspect of this utility model, an integrally cast structure for the outer ring frame of a rotary hearth furnace bottom is provided, comprising multiple cast sections 1, specifically as follows: Figure 1 and Figure 2 As shown;

[0044] A first expansion joint 4 is provided between adjacent pouring sections 1;

[0045] Each of the aforementioned casting sections 1 includes a wall 2, a furnace bottom base 5, and a corner guard 3;

[0046] The corner guard plate 3 includes a first end body 31 and a second end body 32; the first end body 31 is located on the surface of the furnace bottom base 5; the second end body 32 is located on the outer side of the furnace bottom base 5.

[0047] The wall 2 is located on the furnace bottom base 5 and is positioned opposite to the corner guard 3;

[0048] The wall 2, the first end body 31 and the second end body 32 form a groove; the groove is filled with castable 6; a plurality of anchor hooks 9 are provided on the first end body 31 to fix the castable 6 and the casting section 1.

[0049] As an optional embodiment of this utility model, the first expansion joint 4 is provided with a PVC corrugated expansion joint plate.

[0050] As an optional embodiment of this utility model, the width of the first expansion joint 4 is 9-11mm.

[0051] Specifically, PVC corrugated expansion joint plates are used at intervals to separate adjacent pouring sections 1, leaving a certain expansion gap.

[0052] As an optional embodiment of this utility model, the included angle 10 formed by the first end body 31 and the second end body 32 is greater than or equal to 90°.

[0053] As an optional embodiment of the present invention, the first end body 31 is fixed to the furnace bottom base 5 by a plurality of bolts 12 and a plurality of first L-shaped fasteners 11;

[0054] The first L-shaped fastener 11 is located below the furnace bottom base 5, and the bolt 12 passes through the first end body 31, the furnace bottom base 5 and the first L-shaped fastener 11 to fix the three together.

[0055] As an optional embodiment of this utility model, the anchoring hook 9 is a Y-shaped anchoring hook 9.

[0056] Specifically, by using integral casting combined with Y-shaped anchor hooks 9, the refractory material 6 is tightly and firmly bonded to the casting section 1, effectively resisting thermal stress and mechanical stress (such as the force of the material discharge machine), greatly reducing the risk of loosening and breakage, and eliminating material jamming and scraper jamming caused by broken and falling frame bricks.

[0057] As an optional embodiment of this utility model, the first end body 31 is further provided with a support body 8, and an anchoring hook 9 is provided on the support body 8 to ensure the overall firmness and reliability of the cast structure.

[0058] As an optional embodiment of the present invention, the furnace bottom base 5 is provided with a second L-shaped fixing member 13. One end of the second L-shaped fixing member 13 is connected and fixed to the support body 8 by bolts 12, and the other end is connected and fixed to the furnace bottom base 5 by bolts 12 and the first L-shaped fixing member 11.

[0059] As an optional embodiment of this utility model, the spacing between the multiple anchor hooks 9 is ≤200mm to ensure that the castable material is tightly bonded to the substrate and can withstand thermal and mechanical stress.

[0060] As an optional embodiment of this utility model, a second expansion joint is provided between the inner side of the groove and the castable 6; a ceramic fiber blanket 7 is provided in the second expansion joint.

[0061] Specifically, when the first end body 31 is provided with a support body 8, the ceramic fiber blanket 7 needs to be laid on the surface of the support body 8 to reserve a gap for the low cement high strength castable 6 to expand after being heated at high temperature during the later operation.

[0062] As an optional embodiment of this utility model, the width of the second expansion joint is 24-26mm.

[0063] As an optional embodiment of this utility model, the length of each of the casting sections 1 is ≤1.4m.

[0064] As an optional embodiment of this utility model, the castable 6 is a low-cement, high-strength castable.

[0065] Specifically, the low-cement, high-strength castable used in this invention is a commercially available product, specifically model JZL-1H, purchased from Jiaozuo Jinxin Hengtuo New Materials Co., Ltd. It should be noted that the improvement in the integral casting structure of the outer ring frame of the rotary hearth furnace bottom in this invention mainly lies in the improvement of the overall structure, rather than in the improvement of the material or composition of the castable itself.

[0066] Typically, without limitation, this utility model first lays a 25mm ceramic fiber blanket 7 on the surface of the first end body 31 and the second end body 32 of the wall 2 and the corner guard plate 3, as well as on the surface of the support body 8 set on the first end body 31, to reserve gaps for the expansion of the low-cement high-strength castable 6 after being heated at high temperatures during later operation; Y-shaped anchor hooks 9 are cross-welded on the first end body 31 and the support body 8 to ensure the overall firmness and reliability of the castable refractory, and the spacing of the anchor hooks 9 is controlled to be ≤200mm to ensure that the castable body is tightly bonded to the substrate and can withstand thermal and mechanical stress; then the castable refractory 6 is cast into the groove formed by the wall 2, the first end body 31 and the second end body 32 of the casting section 1, and integrally cast into shape.

[0067] Furthermore, the multiple pouring sections 1 described above are poured and supported by segmented formwork installation, with each formwork section having a length of ≤1.4 meters, which facilitates construction operations and quality control.

[0068] Furthermore, an expansion joint with a width of 10mm is reserved between two adjacent pouring sections 1, and the joint is filled with PVC corrugated expansion joint board to accommodate the thermal expansion of the pouring body itself.

[0069] Furthermore, when installing the integral cast-in-place structure of the outer ring frame of the rotary hearth furnace bottom, it is necessary to ensure that there is an appropriate expansion gap between the entire structure and the installation side wall, and the outer side of the gap is not less than 70mm.

[0070] It is also necessary to ensure that the distance between the entire structure and the bottom of the installation wall is controlled at about 130mm.

[0071] Specifically, on-site monolithic casting (especially segmented construction) avoids the arduous process of transporting, aligning, and laying precast bricks, resulting in higher construction efficiency and easier quality control. Later maintenance, such as partial repairs, is also relatively convenient.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A structurally integrally cast outer ring frame for a rotary hearth furnace bottom, characterized in that, Includes multiple pouring sections (1); A first expansion joint (4) is provided between adjacent pouring sections (1); Each of the aforementioned casting sections (1) includes a wall (2), a furnace bottom base (5), and a corner guard (3); The corner guard (3) includes a first end body (31) and a second end body (32); the first end body (31) is located on the surface of the furnace bottom base (5); the second end body (32) is located on the outer side of the furnace bottom base (5); The wall (2) is located on the furnace bottom base (5) and is positioned opposite to the corner guard (3); The wall (2), the first end body (31) and the second end body (32) form a groove; the groove is filled with castable material (6); a plurality of anchor hooks (9) are provided on the first end body (31) to fix the castable material (6) and the casting section (1).

2. The integral casting structure of the outer ring frame of the rotary hearth furnace bottom according to claim 1, characterized in that, The first expansion joint (4) is provided with a PVC corrugated expansion joint plate; The width of the first expansion joint (4) is 9-11 mm.

3. The integral casting structure of the outer ring frame of the rotary hearth furnace bottom according to claim 1, characterized in that, The included angle (10) formed by the first end body (31) and the second end body (32) is greater than or equal to 90°.

4. The integral casting structure of the outer ring frame of the rotary hearth furnace bottom according to claim 1, characterized in that, The first end body (31) is fixed to the furnace bottom base (5) by a plurality of bolts (12) and a plurality of first L-shaped fasteners (11); The first L-shaped fastener (11) is located below the furnace bottom base (5), and the bolt (12) passes through the first end body (31), the furnace bottom base (5) and the first L-shaped fastener (11) to fix the three together.

5. The integral casting structure of the outer ring frame of the rotary hearth furnace bottom according to claim 4, characterized in that, The first end body (31) is also provided with a support body (8), and an anchoring hook (9) is provided on the support body (8); The anchor hook (9) is a Y-type anchor hook.

6. The integral casting structure of the outer ring frame of the rotary hearth furnace bottom according to claim 5, characterized in that, The furnace bottom base (5) is provided with a second L-shaped fastener (13). One end of the second L-shaped fastener (13) is connected and fixed to the support body (8) by bolts (12), and the other end is connected and fixed to the furnace bottom base (5) by bolts (12) and the first L-shaped fastener (11).

7. The integral casting structure of the outer ring frame of the rotary hearth furnace bottom according to claim 5, characterized in that, The spacing between the multiple anchor hooks (9) is ≤200mm.

8. The integral casting structure of the outer ring frame of the rotary hearth furnace bottom according to claim 1, characterized in that, A second expansion joint is provided between the inner side of the groove and the castable material (6); a ceramic fiber blanket (7) is provided in the second expansion joint.

9. The integral casting structure of the outer ring frame of the rotary hearth furnace bottom according to claim 8, characterized in that, The width of the second expansion joint is 24-26 mm.

10. The integral casting structure of the outer ring frame of the rotary hearth furnace bottom according to claim 1, characterized in that, The length of each of the cast sections (1) is ≤1.4m.

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