Tubular tuyere sleeve core device and preparation method thereof

Abstract

The invention belongs to the technical field of pyrometallurgy lead, and particularly relates to a tubular tuyere sleeve core device and a preparation method thereof.The tubular tuyere sleeve core device comprises a 310S stainless steel pipe, a high-purity aluminum oxide ceramic layer located on the inner wall face of the 310S stainless steel pipe and an annular 825 nickel base alloy layer located on the outer wall face of the 310S stainless steel pipe; the 310S stainless steel flange ring is welded at the end part of one end of the 310S stainless steel pipe; according to the prepared tubular tuyere sleeve core device, the stability of the service process of the device and the maximization of comprehensive benefits are realized from the three aspects of improving the structural strength and optimizing the heat-resisting and wear-resisting processes.

Description

Technical Field

[0001] The invention belongs to the technical field of pyrometallurgical lead smelting, and in particular relates to a tubular tuyere sleeve core device and a preparation method thereof. Background Art

[0002] The pyrometallurgical smelting furnace is one of the important equipment in the lead smelting process. In the production process of the smelting furnace, the tuyere sleeve core plays an important role. On the one hand, as a channel for introducing air or other gases, air or specific combustion-supporting gases are transported into the furnace to provide the necessary oxygen or reaction gas for the smelting process and promote the chemical reaction in the furnace. On the other hand, it plays the role of protecting the tuyere. The tuyere sleeve core can reduce the direct erosion and damage of the high-temperature furnace environment to the tuyere and extend the service life of the tuyere. The traditional tuyere sleeve core device is composed of a wear-resistant and high-temperature resistant layer lined with a stainless steel pipe. Under the working conditions of 1200℃~1300℃ and high and low temperature cycles, it is constantly affected by coal powder and airflow, and it is very easy for the wear-resistant layer to fall off or the outer wall of the stainless steel to wear and deform. This forces the structural design to reduce deformation by increasing the thickness of the mechanism, but deflection deformation is still prone to occur at high temperatures. How to optimize the requirements of high temperature resistance, wear resistance and tight fitting of the inner surface of the tuyere sleeve core, ensure the stability of the main structure in service under high temperature conditions, improve the overall structural strength, and extend its life and maintenance cycle has always been a difficult problem that needs to be solved urgently. Summary of the invention

[0003] The purpose of the present invention is to provide a tubular tuyere sleeve core device and a preparation method thereof. Combining the structural service characteristics of the tubular tuyere sleeve core device, the composite design concept of the lining method is adopted, and the tubular structure explosion welding technology and structural mechanics technology theory are coordinated to improve the structural strength of the tubular tuyere sleeve core device and optimize the heat resistance and wear resistance of the inner and outer walls of the pipeline structure, so as to achieve the stabilization of the structural service process and maximize the comprehensive benefits.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is: A tubular air inlet sleeve core device comprises a 310S stainless steel pipe, a high-purity alumina ceramic layer located on the inner wall of the 310S stainless steel pipe, an annular 825 nickel-based alloy layer located on the outer wall of the 310S stainless steel pipe, and a 310S stainless steel flange ring welded to one end of the 310S stainless steel pipe.

[0005] Furthermore, the 825 nickel-based alloy layer has four dovetail grooves evenly distributed along its circumference, and each dovetail groove is arranged to penetrate along the length direction of the 825 nickel-based alloy layer.

[0006] Furthermore, a triangular strip is disposed in each dovetail groove, the bottom of the triangular strip matches the dovetail groove, and the height of the triangular strip is higher than the height of the dovetail groove.

[0007] Furthermore, the thickness of the high-purity alumina ceramic layer is 2 mm, and the thickness of the 825 nickel-based alloy layer is 1.5 mm.

[0008] A method for preparing a tubular tuyere sleeve core device comprises the following steps: S1. Place a bottom plate tooling with a circular pit in the center on the upper part of the platform, pre-roughen the inner wall of the 310S stainless steel pipe, and then vertically insert it into the circular pit and fix it; S2. Use a copper alloy rod with a smooth surface and a length longer than the 310S stainless steel pipe to insert it into the middle of the 310S stainless steel pipe and fix it; S3. The high-purity alumina ceramic material is preheated to a liquid, and then the high-purity alumina is cast into the gap between the copper alloy rod and the 310S stainless steel pipe through a guide tube and a pressure of 20 to 30 MPa is applied to densely fill the high-purity alumina material; S4. After the densely filled high-purity alumina ceramic is cooled to room temperature at a rate of 20°C / min to form a high-purity alumina ceramic layer, the copper alloy rod is extracted, and then cement is poured into the center area of ​​the 310S stainless steel pipe until the inside of the pipe is filled and then naturally solidified; S5. The 825 nickel-based alloy pipe is sleeved on the outside of the overall structure formed by S4 and the 825 nickel-based alloy pipe and the 310S stainless steel pipe are welded into one by explosion, and then the cement located in the center is removed; S6. CNC cut four parallel and evenly spaced dovetail grooves on the outer surface of the 825 nickel-based alloy layer along the length direction of the pipe, fill each dovetail groove with an isosceles triangle strip of 825 nickel-based alloy and weld them together; S7. Fix the 310S stainless steel flange to one end of the 310S stainless steel pipe treated in S6 by ring welding to form a tubular tuyere core device.

[0009] The present invention has the advantages that: 1. The present invention uses a hot-pressing casting method to compound the molten high-purity alumina ceramic material on the inner wall of the roughened 310S stainless steel pipe. The hot-pressing casting method improves the uniformity of the thickness of the ceramic layer on the one hand, ensuring that the wear resistance of the inner wall is uniform during service; on the other hand, it solves the problems of low composite strength and low firmness of the existing spraying method, reduces the risk of the ceramic layer falling off and exposing the main structure due to coal powder or air flow scouring the surface in the tuyere sleeve core, thereby improving the service life of the overall structure; 2. The present invention uses a method of compounding 825 nickel-based alloy on the outer wall of the main body: on the one hand, the heat resistance of the overall structure during service is improved and corrosion is reduced; on the other hand, the selection of nickel-based alloy can still improve the overall structural strength while reducing the thickness of the overall structure; 3. In the present invention, a dovetail groove is prefabricated on the outer side of the overall structure, and isosceles triangle strips of 825 nickel-based alloy are selected and welded into the dovetail groove. On the one hand, considering that the overall structure is thinner than the main body of the structure, the high strength of 825 nickel-based alloy is used to compensate for the slight loss and improve the heat resistance and wear resistance of the surface; on the other hand, the structural stability of the triangle is utilized, and the triangle strips are further used to increase the deformation resistance of the overall structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of the assembly structure of the hot-pressing casting of the high-purity alumina ceramic material of the present invention.

[0011] Figure 2 It is a structural diagram of the high-purity alumina ceramic material after hot pressing casting of the present invention.

[0012] Figure 3 It is an implementation diagram of the composite process for explosive welding of the outer wall of 825 nickel-based alloy of the present invention.

[0013] Figure 4 It is a structural schematic diagram of the dovetail groove and the triangular strip in the present invention.

[0014] Figure 5 It is a schematic diagram of the overall structure of the tubular tuyere sleeve core device of the present invention. DETAILED DESCRIPTION Example

[0015] like Figure 5 As shown, a tubular air inlet sleeve core device includes a 310S stainless steel pipe 1, a high-purity alumina ceramic layer 3 located on the inner wall of the 310S stainless steel pipe, an annular 825 nickel-based alloy layer 4 located on the outer wall of the 310S stainless steel pipe, and a 310S stainless steel flange ring 13 welded to one end of the 310S stainless steel pipe; the 825 nickel-based alloy layer is evenly distributed with four dovetail grooves 11 along its circumference, and each dovetail groove is arranged through the length direction of the 825 nickel-based alloy layer; a triangular strip 12 is clamped in each dovetail groove, the bottom of the triangular strip matches the dovetail groove, and the height of the triangular strip is higher than the height of the dovetail groove. On the one hand, this arrangement takes into account that the overall structure is thinner than the main body of the structure, and uses the high strength characteristics of the 825 nickel-based alloy to compensate for the slight loss and improve the surface heat resistance and wear resistance; on the other hand, the structural stability characteristics of the triangle are used, and the triangular strip is further used to increase the deformation resistance of the overall structure. Preferably, the thickness of the high-purity alumina ceramic layer is 2 mm, and the thickness of the 825 nickel-based alloy layer is 1.5 mm.

[0016] A method for preparing a tubular tuyere sleeve core device comprises placing a 60*200*200mm bottom plate tooling 8 on the upper part of a platform, prefabricating a 70mm diameter and 30mm depth circular pit in the middle area, and then roughening the inner wall of a 310S stainless steel pipe 1, and then vertically inserting it into the circular pit for fixing; selecting a copper alloy rod 2 (reusable) with a diameter of 57mm and a length of 500mm and a smooth surface, and inserting it into the middle of the 310S stainless steel pipe; preheating a high-purity alumina ceramic material to liquid, and then passing it through a guide pipe High-purity alumina is cast into the gap between the copper alloy rod 2 and the 310S stainless steel pipe 1 and a pressure of 20-30Mpa is applied to densely fill the high-purity alumina material, so that the high-purity alumina ceramic layer 3 is closely attached to the inner wall of the 310S stainless steel; after the high-purity alumina ceramic is densely filled, the temperature is cooled to room temperature at a rate of 20℃ / min to form a high-purity alumina ceramic layer, and then the copper alloy rod is pulled out, and then cement material 5 is poured into the central area of ​​the 310S stainless steel pipe until it fills the inside of the pipe and solidifies naturally; an inner diameter of 72m is used. The 825 nickel-based alloy pipe with a wall thickness of 1.5mm and a length of 480mm is sleeved on the outside of the overall structure and placed at a certain interval 10. The cylindrical medicine box 6 is placed by explosion method, and the explosives 7 are filled. The whole is placed on a tooling 9 with an explosive filling cavity at the bottom and fixed, and the explosion method composite operation is carried out according to the design; after the overall structure is composited by the explosion method, the center cement 5 is taken out and filled, and 4 lines with a depth of 2mm, a width of 23mm, a length of 400mm, and a bottom angle of 40° are prefabricated on the outer surface of the 825 nickel-based alloy layer 4 along the length direction of the pipe. Dovetail groove 11, 4 dovetail grooves are evenly distributed along the outer surface of 825 nickel-based alloy layer 4, and at the same time, 825 nickel-based alloy isosceles triangle strip 12 with a bottom edge of 22.5mm, a height of 10mm, two oblique sides of 15mm, and a length of 400mm is prepared, which is inserted into the prefabricated dovetail groove along the bottom edge and welded and fixed on the outside, and a 310S stainless steel flange ring 13 with an inner diameter of 71mm, an outer diameter of 170mm, and a thickness of 50mm is welded and fixed to one end of the 310S stainless steel pipe to form the final overall structure, that is, a tubular air inlet core device is obtained.

[0017] Performance measurement 1.1 Process (1) Through the industrial analysis part of Ansys finite element simulation software, digital simulation of thermodynamic pressure was selected for testing, and a reasonable structural design was selected according to the color changes in the simulation screen; (2) The hot-pressing casting process is used to bond the high-purity alumina ceramic material to the 310S stainless steel pipe with a roughened inner wall; (3) Use explosive welding technology to achieve the outer wall bonding of 825 nickel-based alloy pipe and 310S stainless steel pipe; (4) Using CNC technology, four dovetail grooves are prefabricated along the diameter perpendicular direction on the outside of the overall structure; (5) Preparation of 825 alloy triangular strip structure; (6) Insert the 825 alloy triangle strip into the prefabricated dovetail groove and weld it in place; (7) Fix the 310S flange ring to one end of the main structure by welding to finally form an overall product structure; All surfaces: Before each layer is processed, it is cleaned with organic solvent to ensure that there are no stains. Before all welding is implemented, the surface roughness of the outer material is less than 1.6nm, and the surface roughness of the inner material is greater than 3.2nm.

[0018] 1.2 Basic Process of Performance Testing (1) Prepare to meet the technical requirements and use qualified 310S stainless steel pipes, copper alloy bars, 825 nickel-based alloy pipes, and 825 nickel-based alloy triangle strips; (2) The high-purity alumina ceramic layer is bonded to the inner wall of the 310S stainless steel pipe by hot pressing casting. The force required to peel the pressure-sensitive tape from the high-purity alumina ceramic layer is tested by the 180° peeling method according to GB / T2792-2014 "Test method for peel strength of adhesive tape". The peel strength between the high-purity alumina ceramic layer and the 310S stainless steel is ≥30N / mm. (3) The explosive composite method is used to bond the 825 nickel-based alloy pipe to the outer wall of the 310S stainless steel. The GB / T228.1 "Tensile Test of Metallic Materials" is used to prepare a specimen of a specific shape, so that the bonding surface of the 825 nickel-based alloy and the 310S stainless steel parallel to the test force direction is subjected to tensile force until separation. The evaluation result shows that the bonding strength is ≥210MPa; (4) The finite element method is used to simulate the thermodynamic state, select the most suitable dovetail groove structure, and simulate the structural mechanics characteristics, selecting a specific 825 nickel-based alloy triangular strip structure and distribution rules; (5) Test the bonding strength of the welded 825 nickel-based alloy triangle strip; (6) The product was subjected to thermal testing, with a high temperature of 1300°C for one hour and a low temperature of 25°C for one hour, in a reciprocating cycle. No structural deformation was observed during the repeated temperature difference tests. The inner wall sandblasting test pressure was 1.05 times the working pressure and was greater than 5MPa. The high-purity alumina ceramic layer and the 310S stainless steel pipe were observed at the test pressure for 15 minutes without any wear or shedding.

Claims

1. A tubular tuyere core device, characterized in that: The invention comprises a 310S stainless steel pipe, a high-purity alumina ceramic layer located on the inner wall of the 310S stainless steel pipe, an annular 825 nickel-based alloy layer located on the outer wall of the 310S stainless steel pipe, and a 310S stainless steel flange ring welded to one end of the 310S stainless steel pipe.

2. The tubular tuyere sleeve core device according to claim 1, characterized in that: The 825 nickel-based alloy layer has four dovetail grooves evenly distributed along its circumference, and each dovetail groove is arranged to penetrate along the length direction of the 825 nickel-based alloy layer.

3. The tubular tuyere sleeve core device according to claim 2, characterized in that: A triangular strip is arranged in each dovetail groove, the bottom of the triangular strip matches the dovetail groove, and the height of the triangular strip is higher than the height of the dovetail groove.

4. The tubular tuyere sleeve core device according to claim 3, characterized in that: The thickness of the high-purity alumina ceramic layer is 2 mm, and the thickness of the 825 nickel-based alloy layer is 1.5 mm.

5. The method for preparing the tubular tuyere core device according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Place a bottom plate tooling with a circular pit in the center on the upper part of the platform, pre-roughen the inner wall of the 310S stainless steel pipe, and then vertically insert it into the circular pit and fix it; S2. Use a copper alloy rod with a smooth surface and a length longer than the 310S stainless steel pipe to insert it into the middle of the 310S stainless steel pipe and fix it; S3. The high-purity alumina ceramic material is preheated to a liquid, and then the high-purity alumina is cast into the gap between the copper alloy rod and the 310S stainless steel pipe through a guide tube and a pressure of 20 to 30 MPa is applied to densely fill the high-purity alumina material; S4. After the densely filled high-purity alumina ceramic is cooled to room temperature at a rate of 20°C / min to form a high-purity alumina ceramic layer, the copper alloy rod is extracted, and then cement is poured into the center area of ​​the 310S stainless steel pipe until the inside of the pipe is filled and then naturally solidified; S5. The 825 nickel-based alloy pipe is sleeved on the outside of the overall structure formed by S4 and the 825 nickel-based alloy pipe and the 310S stainless steel pipe are welded into one by explosion, and then the cement located in the center is removed; S6. CNC cut four parallel and evenly spaced dovetail grooves on the outer surface of the 825 nickel-based alloy layer along the length direction of the pipe, fill each dovetail groove with an isosceles triangle strip of 825 nickel-based alloy and weld them together; S7. Fix the 310S stainless steel flange to one end of the 310S stainless steel pipe treated in S6 by ring welding to form a tubular tuyere core device.

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