Composite submersed nozzle

Abstract

A composite submersed nozzle comprises a nozzle body, a wrist portion is arranged at the upper end of the nozzle body, a slag line portion is arranged at the lower end of the nozzle body, the slag line portion is formed by compositing a zirconium-carbon anti-erosion layer and a fused quartz layer, and the zirconium-carbon anti-erosion layer and the fused quartz layer are sequentially arranged from inside to outside. Lining layers are arranged on the inner wall of the nozzle body and the inner wall of the zirconium-carbon anti-erosion layer; and a tapping hole is formed in the bottom end of the slag line part. The nozzle body adopts the fused quartz tube which is made of quartz, so that the thermal expansion coefficient is small, the thermal shock resistance coefficient is high, and the nozzle can be used without baking. By additionally arranging the lining layer and the composite zirconium slag line part, high-temperature crystal transformation of quartz can be slowed down, the service life of the quartz can be prolonged, meanwhile, the quartz is prevented from reacting with manganese, titanium and iron elements in molten steel to generate low-melt substances, the low-melt substances are prevented from being peeled off along with scouring of the molten steel, and therefore the product quality of alloy steel is improved.

Description

Technical Field

[0001] The utility model relates to a submerged nozzle, and more specifically, to a composite submerged nozzle. Background Art

[0002] As one of the "three major parts" in continuous casting, the application of the submerged nozzle in iron and steel enterprises has greatly improved the continuous casting level. In the initial stage of continuous casting, fused silica submerged nozzles were used. Due to their small thermal expansion coefficient, high chemical stability, good volume stability, high temperature thermal shock resistance, high mechanical strength, and resistance to acid slag erosion, they could meet the requirements for casting ordinary carbon steel, low manganese steel (W(Mn)<0.6%), aluminum killed steel, etc. However, when quartz is used at high temperatures for a long time, it will undergo polymorphic transformation and precipitate cristobalite, resulting in cracks and spalling of the nozzle. In addition, quartz itself is affected by the composition of molten steel and the alkalinity of the protective slag, making the nozzle made of it vulnerable to erosion. For example, when casting high manganese steel, quartz easily reacts with manganese elements in the molten steel to form manganese silicate. Quartz is an acidic material and is only suitable for protective slag with an alkalinity less than 1. Otherwise, when the slag line part is severely eroded, the "necking phenomenon" is likely to occur, and in severe cases, the slag line part of the nozzle will break. These are the deficiencies of the existing technology. Summary of the Utility Model

[0003] The purpose of the utility model is to solve the problems raised in the above background art, and then a composite submerged nozzle is proposed to achieve the purpose of extending the service life of the fused silica nozzle and making the fused silica nozzle more reliable in use.

[0004] The technical solution adopted by the utility model to solve its technical problems is: a composite submerged nozzle, including a nozzle body. A hollow channel is arranged inside the nozzle body. A wrist part is arranged at the upper end of the nozzle body, and a slag line part is arranged at the lower end of the nozzle body. The slag line part is composed of a zirconium carbon erosion-resistant layer and a fused silica layer, and the zirconium carbon erosion-resistant layer and the fused silica layer are arranged in sequence from the inside to the outside. Lining layers are arranged on the inner wall of the nozzle body and the inner wall of the zirconium carbon erosion-resistant layer. A tapping hole is arranged at the bottom end of the slag line part.

[0005] A further improvement of the utility model is that the nozzle body is made of a fused silica tube.

[0006] A further improvement of the utility model is that a first bonding layer is arranged between the inner wall of the nozzle body and the lining layer.

[0007] A further improvement of the utility model is that a second bonding layer is arranged between the zirconium carbon erosion-resistant layer and the fused silica layer.

[0008] A further improvement of the utility model is that the nozzle body is tubular.

[0009] A further improvement of the present utility model is that the thickness of the zirconium-carbon erosion-resistant layer is 20-45 mm.

[0010] A further improvement of the present utility model is that the thickness of the fused quartz layer is 1-3 mm.

[0011] A further improvement of the present utility model is that the thickness of the inner lining layer is 5-10 mm.

[0012] The beneficial effects of the present utility model are as follows: The nozzle body of the present utility model adopts a fused quartz tube, which is made of quartz material, has a small thermal expansion coefficient and a high thermal shock resistance coefficient, and can be used without baking. By adding an inner lining layer and a composite zirconium-based slag line part, the high-temperature polymorphic transformation of quartz can be slowed down to extend the service life. At the same time, it can prevent the reaction of quartz with manganese, titanium, and iron elements in molten steel to form low-melting substances, which are peeled off by the scouring of molten steel, thereby improving the product quality of alloy steel. The above advantages can make the quartz nozzle more stable and reliable in continuous casting production, and significantly improve its service life. Description of the Drawings

[0013] Figure 1 It is a schematic structural diagram of the first embodiment of the present utility model;

[0014] Figure 2 It is a schematic structural diagram of the second embodiment of the present utility model.

[0015] In the figure, 1 is the nozzle body, 11 is the wrist part, 12 is the slag line part, 13 is the hollow channel, 2 is the inner lining layer, 3 is the zirconium-carbon erosion-resistant layer, 4 is the fused quartz layer, and 5 is the tapping hole. Detailed Embodiments

[0016] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model. The present utility model will be further described in conjunction with the drawings and embodiments:

[0017] Embodiment 1: As Figure 1As shown in the figure, a composite submerged nozzle includes a nozzle body 1. A hollow channel 13 is provided inside the nozzle body 1. A wrist part 11 is provided at the upper end of the nozzle body 1. A slag line part 12 is provided at the lower end of the nozzle body 1. The slag line part 12 is composed of a zirconium carbide erosion-resistant layer 3 and a fused quartz layer 4 which are compounded. The zirconium carbide erosion-resistant layer 3 and the fused quartz layer 4 are arranged in sequence from inside to outside. A lining layer 2 is provided on the inner wall of the nozzle body 1 and on the inner wall of the zirconium carbide erosion-resistant layer 3. A tapping hole 5 is provided at the bottom end of the slag line part 12.

[0018] Among them, the nozzle body 1 is made of a fused quartz tube.

[0019] By adding the lining layer 2 and the compounded slag line part 12 (the zirconium carbide erosion-resistant layer 3 and the fused quartz layer 4 are compounded), the present utility model can slow down the high-temperature polymorphic transformation of the original quartz tube, extend the service life, and at the same time, prevent the reaction between quartz and manganese, titanium, and iron elements in the molten steel to generate low-melting substances, which are peeled off by the scouring of the molten steel, thereby improving the product quality of alloy steel.

[0020] Specifically, the raw material components and mass percentages of the lining layer 2 are: 35-60% alumina hollow spheres, 15-30% graphite, 10-15% fused quartz, 3-10% zircon mullite, 3-10% additives. Among them, the additives are mainly composed of one or several of carbon black, silicon carbide, boron carbide, silicon nitride, boron nitride, and metal silicon powder in any combination.

[0021] Furthermore, a first bonding layer is provided between the inner wall of the nozzle body 1 and the lining layer 2. The material of the first bonding layer can be: sodium silicate, aluminum phosphate, or phenolic resin. A second bonding layer is provided between the zirconium carbide erosion-resistant layer 3 and the fused quartz layer 4. The material of the second bonding layer can be: sodium silicate, aluminum phosphate, or phenolic resin.

[0022] Furthermore, the thickness of the zirconium carbide erosion-resistant layer 3 is 20-45 mm. The thickness of the fused quartz layer 4 is 1-3 mm. The thickness of the lining layer 2 is 5-10 mm.

[0023] The present utility model provides a composite submerged nozzle. The raw material components and mass percentages of the lining layer are: 60% 0.3 mm alumina hollow spheres, 15% -198 graphite, 15% 325-mesh fused quartz, 7% 0.71-0 mm zircon mullite, 2% 325-mesh metal silicon powder, 1% silicon carbide, and 5% phenolic resin added additionally as a binder, 4% liquid resin. The above raw materials of the lining layer 2 are subjected to batching, mixing, granulating, drying, and aging. Among them, the lining layer is first formed at 18 MPa, and the formed thickness is 6 mm. The forming method can adopt isostatic pressing composite forming or sleeve one-time forming.

[0024] The nozzle body 1 is a fused silica tube made of fused silica as raw material, formed by slurry casting and sintered at high temperature. The binder for bonding the fused silica tube, the inner lining layer 2, the zirconium carbide erosion-resistant layer 3 and the fused silica layer 4 can be sodium silicate, aluminum phosphate or phenolic resin. After the blank is bonded and formed, it is then fired to obtain the finished product.

[0025] Embodiment 2: As Figure 2 shown, different from Embodiment 1, both the inner surface and the outer surface of the wrist part are arc-shaped surfaces.

[0026] The above shows and describes the basic principles, main features and advantages of the present utility model. Those skilled in the art should understand that the present utility model is not limited by the above embodiments. The above embodiments and the descriptions in the specification only illustrate the principles of the present utility model. Without departing from the spirit and scope of the present utility model, the present utility model will have various changes and improvements, and all these changes and improvements fall within the scope of protection required by the present utility model. The scope of protection required by the present utility model is defined by the appended claims and their equivalents.

Claims

1. A composite immersion nozzle, comprising a nozzle body, wherein a hollow channel is provided in the nozzle body, characterized in that: A wrist portion is provided at the upper end of the nozzle body, and a slag line portion is provided at the lower end of the nozzle body. The slag line portion is composited by a zirconium-carbon anti-corrosion layer and a molten quartz layer, and the zirconium-carbon anti-corrosion layer and the molten quartz layer are arranged in sequence from the inside to the outside; an inner lining layer is provided on the inner wall of the nozzle body and the inner wall of the zirconium-carbon anti-corrosion layer; a steel outlet is provided at the bottom end of the slag line portion.

2. The composite submerged nozzle according to claim 1, characterized in that: The nozzle body is made of a fused quartz tube.

3. The composite submerged nozzle according to claim 2, characterized in that: A first bonding layer is arranged between the inner wall of the nozzle body and the inner lining layer.

4. The composite submerged nozzle according to any one of claims 1 to 3, characterized in that: A second bonding layer is arranged between the zirconium-carbon anti-corrosion layer and the fused quartz layer.

5. The composite submerged nozzle according to claim 1, characterized in that: The nozzle body is tubular.

6. The composite submerged nozzle according to claim 1, characterized in that: The thickness of the zirconium-carbon anti-corrosion layer is 20-45 mm.

7. The composite submerged nozzle according to claim 1, characterized in that: The thickness of the fused silica layer is 1-3 mm.

8. The composite submerged nozzle according to claim 1, characterized in that: The thickness of the lining layer is 5-10 mm.

Images