Blowering spray guns used for gas injection, their applications and manufacturing methods

Abstract

This invention relates to a blower lance for gas injection in metallurgical processes. The blower lance comprises a cylindrical nozzle core and a refractory shell, wherein the refractory shell comprises n+1 refractory tubular portions and n or more refractory annular structures, wherein two adjacent refractory tubular portions in each group are connected via refractory annular structures, and wherein n is an integer of 1 or greater. The invention also relates to the use of this blower lance and its manufacturing method.

Description

Technical Field

[0001] This invention relates to a blower gun for gas injection. The invention also relates to the use of the blower gun for gas injection and its manufacturing method. Background Technology

[0002] Blow lances are used for gas blowing in metallurgical processes. They are used to blow gases over or through molten metal during metallurgical processes such as oxygen steelmaking, or to degas molten metal. Particularly during degassing (where inert gases such as nitrogen or argon are blown into the molten metal or alloy composition by immersing the blow lance in the molten metal or alloy composition), the chemical, thermal, and mechanical stresses on the blow lance are considerable. During immersion, the tip of the blow lance is exposed to thermal stress due to the high temperature of the molten metal. Furthermore, a large amount of corrosive slag may be present near the surface of the molten metal. The high density and movement of the molten metal also contribute to mechanical stress throughout the blow lance, as the entire lance moves through a heavy and often viscous liquid, resulting in strong mechanical momentum, particularly in the slag region of the blow lance. Therefore, blow lance materials need to meet a variety of different, often contradictory, requirements.

[0003] Blast lances used for gas injection in metallurgical applications are typically formed from refractory materials such as refractory concrete. Various types of refractory concrete with different properties are known to those skilled in the art. Refractory concretes generally require the use of refractory bonding systems to enable them to withstand high-temperature conditions. Materials may include calcium aluminate cement, refractory clay, silica, and minerals with high alumina content. For example, bauxite concrete has particularly good high-temperature resistance and resistance to temperature changes, while high-alumina concrete has good chemical stability. Conversely, concrete containing refractory clay of higher value may be used for the structural (upper) portion of the blast lance, which requires lower chemical or thermal stability.

[0004] Japanese Unexamined Patent Application No. 2004317097 discloses a method for forming a blower lance by horizontal casting, wherein one or more baffles are arranged within the lance casting, and different types of refractory coatings are cast in different portions formed by the baffles. The baffles can be made of acrylic resin, plastic, paper, or rubber, and need to be removed after casting the integral refractory coating, thus increasing the number of process steps and potentially leaving gaps between adjacent portions of the refractory coating in the blower duct.

[0005] Therefore, existing technologies have problems. Summary of the Invention

[0006] This invention is defined by the appended claims.

[0007] Specifically, the present invention is implemented by a blower gun for gas injection in a metallurgical process, the blower gun comprising a cylindrical nozzle core and a refractory shell, wherein the refractory shell comprises n+1 refractory tubular portions and n or more refractory annular structures, wherein two adjacent refractory tubular portions in each group are connected via refractory annular structures, and wherein n is an integer of 1 or greater. In one embodiment, the blower gun for gas injection is a blower gun for vertical gas injection. It has been found that the blower gun according to the present invention does not exhibit the problems of the prior art.

[0008] In one embodiment of the present invention, the refractory annular structure may have an outer diameter corresponding to the outer diameter of the refractory tubular portion and an inner diameter corresponding to the inner diameter of the refractory tubular portion. According to this embodiment, good structural stability of the blower gun according to the present invention can be achieved.

[0009] In one embodiment of the invention, each refractory annular structure may be made of the same material as any of the adjacent refractory tubular portions connected to that refractory annular structure. According to this embodiment, good structural uniformity can be achieved in the blower gun according to the invention.

[0010] In one embodiment of the invention, the refractory annular structure and the refractory tubular portion can be made of concrete. Refractory concrete has been found to be particularly suitable for the present invention.

[0011] In one embodiment of the invention, each refractory annular structure may also be equipped with a groove pin for securing the annular structure to the adjacent refractory tubular portion. According to this embodiment, the connection between the annular structure and the refractory tubular portion it contacts is more stable. This effect is particularly pronounced when the groove pin is made of steel such as stainless steel.

[0012] In one embodiment of the invention, each refractory annular structure consists of two semi-annular portions connected by mortar. This particular structure has been found to make the manufacture of blower guns easier and more efficient.

[0013] In one embodiment of the invention, a first refractory tubular portion is made of a first material, and a second refractory tubular portion is made of a second material different from the first material. According to this embodiment, different material properties can be assigned to different portions of the blower gun. Furthermore, a third refractory tubular portion may be made of a third material different from the first material, the second material, or both the first and second materials. Depending on the circumstances, several portions of the blower gun according to the invention may require several specific material property requirements, which can be optimally achieved using many different portions made of different refractory materials. Similarly, according to another embodiment of the invention, additional refractory tubular portions made of other different refractory materials may exist.

[0014] Furthermore, a part of this invention relates to the use of the blower gun according to the invention in gas blowing in metallurgical processes. It has been found that the blower gun according to the invention has a longer service life than blower guns according to the prior art. In one embodiment, the invention relates to the use of the blower gun according to the invention in vertical gas blowing in metallurgical processes.

[0015] Furthermore, a part of the present invention is a method for forming a blower gun according to the invention. The method includes the following steps: providing a longitudinal horizontal casting mold for casting the blower gun; inserting n or more refractory annular structures into the longitudinal horizontal casting mold; inserting a cylindrical spray gun core into the longitudinal horizontal casting mold such that the cylindrical spray gun core passes through the central holes of the n or more annular ceramic structures; casting n+1 refractory tubular portions, wherein each refractory tubular portion is separated from adjacent refractory tubular portions by the refractory annular structures; allowing the casting material to solidify; and removing the longitudinal horizontal casting mold, wherein n is an integer of 1 or greater. This particular production method is faster and more efficient than methods according to the prior art, and yields an advantageous blower gun according to the invention. Attached Figure Description

[0016] The invention will be further described with reference to the following figures:

[0017] Figure 1 A diagram shows a casting mold for forming a blower gun according to the invention, wherein a refractory annular structure has been inserted prior to casting the refractory tubular element;

[0018] Figure 2 It shows Figure 1 A diagram of the casting mold after casting refractory tubular components;

[0019] Figure 3 It shows Figure 1 and Figure 2 The image shows the casting blower gun after demolding;

[0020] Figure 4 It shows in Figure 1 and Figure 2 A side view of the refractory annular structure of a portion of a cast blower gun having two adjacent refractory tubular elements after demolding.

[0021] Figure 5 A diagram of an exemplary fire-resistant ring structure is shown;

[0022] Figure 6 A diagram of an exemplary fire-resistant annular structure is shown, which includes slotted pins for securing and reinforcing the annular structure to an adjacent fire-resistant tubular portion.

[0023] It should be understood that the following description and reference to the accompanying drawings relate to exemplary embodiments of the invention and are not intended to limit the scope of the claims. Detailed Implementation

[0024] The present invention, according to the appended claims, provides blower lances for gas blowing in metallurgical processes, their uses, and their manufacture. According to the invention, blower lances with good durability and lifespan can be provided. The characteristics of the blower lances according to the invention can also be fine-tuned to adapt them to specific requirements that may exist in a given environment. In one embodiment, the blower lance is used for vertical gas blowing in a metallurgical process.

[0025] According to one aspect of the invention, a blower 1 is provided, which is suitable for vertical gas blowing in metallurgical processes and can be manufactured by horizontal casting. Specifically, the blower 1 includes a cylindrical nozzle core 2 and a refractory shell 3, wherein the refractory shell 3 includes a plurality of refractory tubular portions 4 separated by refractory annular structures 5. Given this arrangement, according to the invention, the refractory shell 3 of the blower 1 according to the invention includes alternately arranged refractory tubular portions 4 and refractory annular portions 5, wherein the longitudinal end of the blower 1 may be formed by the refractory tubular portions 4. Preferably, at least one longitudinal end of the blower 1 is formed by a refractory annular portion 5, typically opposite the free plate side of the blower 1. Therefore, the blower 1 includes n or more refractory annular structures 5 and n+1 refractory tubular portions 4, where n is an integer of 1 or greater. In one embodiment, a longitudinal end of the blower 1, typically the free plate side end, is formed of a non-ceramic material (e.g., metal).

[0026] Blowering spray gun and production method

[0027] Blower lances used for gas blowing in metallurgical processes are well known in the art. They are typically formed by a hollow lance core through which gas is blown out. The lance core is ideally protected by a stable shell, such as a refractory shell. A refractory shell is essential, especially where the blower lance may be exposed to high temperatures. Furthermore, various additional factors must be considered when designing a blower lance, depending on its intended use. These may include the chemical environment, thermal stress caused by temperature changes, mechanical stress the lance may experience during use, cost, ease of manufacture, maneuverability, or overall weight.

[0028] According to the present invention, a blower gun 1 can be provided, wherein the refractory shell 3 of the gun core 2 is composed of separate portions that can meet different requirements. The refractory shell 3 includes a plurality of refractory tubular portions 4 arranged side by side along the gun core 2, and these refractory tubular portions 4 are separated by a refractory annular structure 5. The refractory tubular portions 4 and the refractory annular structure 5 together constitute the refractory shell 3 of the gun core 2, thereby forming the blower gun 1 of the present invention.

[0029] Figure 3 An exemplary blower gun 1 according to the present invention is shown, which consists of four (n+1) separate refractory tubular portions 4, which are separated by three (n) refractory annular structures 5 and are straight after demolding.

[0030] The blower lance 1 according to the invention may include refractory tubular sections 4 made of different materials, each refractory tubular section 4 having different properties as needed. For example, any refractory tubular section 4 may be made of a specific refractory concrete with good mechanical properties. Alternatively, the specific refractory concrete of any refractory tubular section 4 may have good chemical stability. Alternatively, the specific refractory concrete of any refractory tubular section 4 may have good value while providing satisfactory material properties. Alternatively, the specific refractory concrete of any refractory tubular section 4 may present a good trade-off between different properties.

[0031] According to the invention, the refractory annular structure 5 of the blower lance 1 is positioned between adjacent refractory tubular portions 4. Through the process of forming the blower lance 1 (which is also part of the invention), the refractory tubular portions 4 naturally adhere to the refractory annular structure 5. This... Figure 4 As shown in the figure, Figure 4A side view of the refractory annular structure 5 in contact with two refractory tubular elements 4 is shown. This adhesion is strong when the refractory annular structure 5 and the refractory tubular portions 4 are made of refractory concrete, particularly when the material of the refractory annular structure 5 is the same as that of one of the adjacent refractory tubular portions 4. According to the invention, combined with the structural stabilizing effect of the cylindrical spray gun core 2, the adhesion between the various elements constituting the blower gun 1 results in good overall structural stability, thereby providing a robust and hard blower gun 1.

[0032] The production method according to the invention includes a horizontal casting process for a blower gun 1. According to a specific production method of the invention, a gun core 2 and a refractory annular structure 5 are provided. The refractory annular structure 5 is placed around the gun core 2 within a longitudinal casting mold 7, positioned at a desired location (where the refractory annular structure 5 should be found in the finished blower gun 1), and positioned such that the gun core 2 passes through the central hole of the refractory annular structure 5. To improve adhesion between the gun core 2 and the cast refractory tubular portion 4, the gun core 2 may be provided with a reinforcing anchoring system 8. This... Figure 1 As shown in, Figure 1 Two separate refractory annular structures 5 can be seen, positioned at different intervals around the spray gun core 2 within the casting mold 7. To achieve a good seal between the different portions formed by the refractory annular structures 5, it is advantageous that the inner diameter of the refractory annular structure 5 corresponds to the outer diameter of the spray gun core 2. Furthermore, the inner diameter of the casting mold 7 should correspond to the outer diameter of the refractory annular structure 5. Therefore, the inner and outer diameters of the refractory annular structure 5 will respectively correspond to the inner and outer diameters of the cast refractory tubular portion 4.

[0033] With the refractory annular structure 5 and the spray gun core 2 located within the casting mold 7, n+1 refractory tubular sections 4 can now be cast into the casting mold 7. For example... Figure 2As shown, the n+1 refractory tubular sections 4 can be made of different materials and are separated by a refractory annular structure 5 within the casting mold 7. It will be apparent to those skilled in the art that during the casting of the n+1 refractory tubular sections 4, good dispersion of the casting within the distribution portion of the casting mold 7 must be ensured to avoid the formation of air bubbles within the casting material, compact the refractory material, and ensure optimal possible contact with the refractory annular structure 5. This can be achieved using vibration, self-flowing castables, or other means known to those skilled in the art. Castables are generally considered to be self-flowing castables, provided they are capable of flowing and degassing without the application of external energy (e.g., vibration energy). When using vibration to compact the refractory material, vibration is typically performed at a frequency in the range of 8,000 to 15,000 vibrations per minute. The required vibration frequency is known to depend on parameters such as the type of mixture, the temperature of the mixture, the size and shape of the mold, and the type of vibrating equipment used, and those skilled in the art will adjust the vibration frequency accordingly.

[0034] To obtain a spray gun core 1 with a uniform surface, it is advantageous to cast the refractory tubular portion 4 with its outer diameter corresponding to the outer diameter of the refractory annular structure 5. To achieve this, the inner diameter of the casting mold 7 should correspond to the outer diameter of the refractory annular structure 5.

[0035] After casting n+1 refractory tubular sections 4, demolding can be performed in a manner known to those skilled in the art.

[0036] According to the present invention, the blower gun 1 formed by the method of the present invention includes a gun core 2 and a refractory gun housing 3, the refractory gun housing 3 further including n+1 refractory tubular portions 4 separated by n refractory annular structures 5. Additional refractory annular structures 5 may be present at one or any of the longitudinal ends of the blower gun 1, resulting in more than n refractory annular structures 5. The n+1 refractory tubular portions 4 may be made of different refractory materials with different properties, and the n or more refractory annular structures 5 may be made of the same refractory material as one of the adjacent refractory tubular portions 4.

[0037] Refractory tubular section

[0038] As described above, the refractory tubular portion 4 of the blower lance 1 according to the present invention is cast within the casting mold 7 into a portion formed by the refractory annular structure 5. Assuming that the dimensions of the refractory annular structure 5 preferably correspond to the casting mold 7 and the lance core 2, such that the outer diameter of the lance core 2 corresponds to the inner diameter of the refractory annular structure 5 and the inner diameter of the casting mold 7 corresponds to the outer refractory annular structure 5, then the inner and outer diameters of the refractory tubular portion 4 will preferably correspond to the inner and outer diameters of the refractory annular structure 5, respectively.

[0039] Depending on the desired properties, the refractory tubular portion 4 can be made of different materials. They are preferably made of refractory concrete, as these materials are well-known and generally easy to cast using the methods according to the invention. For example, high-alumina concrete can be used in areas requiring good chemical resistance. Furthermore, bauxite-based concrete can be used in areas requiring good thermal stability. Additionally, refractory clay-based concrete of better quality can be used in areas where refractory requirements are less stringent but structural stability and shielding are needed.

[0040] The casting process for forming the refractory tubular portion 4 is carried out using methods known to those skilled in the art. To obtain a dense material of good quality with good adhesion and uniformity, the material should be subjected to vibration during casting to aid solidification. After demolding, the refractory tubular portion 4 adheres to the lance core 2 (optionally assisted by a reinforcing anchoring system 8) and to the refractory annular structure 5, thereby forming together the blower lance 1 according to the invention.

[0041] Refractory ring structure

[0042] The refractory annular structure 5 serves as a partition between adjacent refractory tubular sections 4. As described above, they are placed in the desired position within the casting mold 7 around the spray gun core 2. To improve the separation between the different parts during the casting process, it is advantageous that the inner diameter of the refractory annular structure 5 corresponds to the outer diameter of the spray gun core 2, and the outer diameter of the refractory annular structure 5 corresponds to the inner diameter of the casting mold 7.

[0043] To facilitate installation of the refractory annular structure 5 during production, the refractory annular structure 5 can be formed from separate semi-annular portions 5a and 5b. This specific embodiment is described by... Figure 5 As shown. This arrangement is particularly necessary when the spray gun core 2 is equipped with a reinforced anchoring system 8, in order to allow the spray gun core 2 to pass through the central hole of the refractory annular structure 5. Therefore, during the production process, the refractory annular structure 5 will be provided in the shape of semi-annular portions 5a and 5b, and one of the semi-annular portions 5a will be installed in the casting mold 7 (after which the spray gun core 2 will be installed), and then the refractory annular structure 5 will be formed by placing the corresponding second semi-annular portion 5b.

[0044] The refractory annular structure 5 can be made of different materials, although they are preferably made of refractory concrete. In particular, it is advantageous that the refractory annular structure 5 is made of the same material as any of the adjacent refractory tubular portions 4. This results in improved performance and structural uniformity of the finished blower 1, and improved adhesion between the refractory tubular portions 4 and the refractory annular structure 5.

[0045] Grooving pin

[0046] According to one embodiment of the present invention, the refractory annular structure 5 may be provided with a grooved pin 6. This is in Figure 6 As shown in the diagram. In the case where the refractory annular structure 5 is formed by semi-annular portions 5a and 5b, a grooved pin 6 may also be present. After the casting and solidification of the refractory tubular portion 4, the grooved pin 6 serves to hold the refractory tubular portion 4 in place on either side of the refractory annular structure 5. This provides additional stability to the blower lance 1 according to the invention. The grooved pin can be made of metal, such as steel, for example, stainless steel.

[0047] It should be noted that the present invention may include any combination of the features and / or limitations mentioned herein, except for combinations of mutually exclusive features. The foregoing description is intended to illustrate specific embodiments of the invention. However, it will be apparent to those skilled in the art that many modifications and variations can be made to the embodiments described herein. All such modifications and variations are within the scope of the invention as defined by the appended claims.

[0048] Example

[0049] The blower gun is formed according to the method of the present invention. A 3800mm casting mold with an inner diameter of 230mm and a gun core with an outer diameter of about 57mm are used. A concrete ring is provided as the refractory annular structure, having an outer diameter of 227mm, an inner diameter of about 57mm, and a thickness of 40mm. The concrete ring is made into semi-rings. Three pairs of semi-rings and the gun core are placed in the casting mold at such intervals to form sections of approximately 580mm (head section), 1160mm (molten pool section), 960mm (slag section), and 980mm (cold section). Each pair of semi-rings is joined together using mortar, and by doing so, a complete ceramic disc is formed. Each disc is provided with four double-groove pins to reinforce and secure the refractory annular section using four anchors located at each surface of the refractory tubular section.

[0050] During the casting process, the four sections formed are filled with different types of concrete (all supplied by CalderysDeutschland GmbH). The head section is filled with Calde Cast LT 96SP RSH (tubular alumina-based concrete). The molten pool section is filled with Calde Cast LB 85G8(TKS)RSH (bauxite-based concrete). The slag section is filled with Calde Cast LT 96SP RSH (tubular alumina-based concrete). The cold section is filled with Calde Cast F50 G10 (refractory clay-based concrete). After vibration-assisted casting, solidification, and demolding, the blower lance is ready for use.

[0051] For this type of production, existing casting molds can be used without needing to be modified to suit this specific production method. Furthermore, this production method is safe and easy to operate.

[0052] In some embodiments, the presence of the concrete ring structure improves the connection between cast components, eliminating the need to remove the concrete ring structure itself before using the blower gun. During use, the blower gun according to the present invention exhibits improved durability compared to blower guns formed by different methods.

[0053] Figure Labels

[0054] 1. Blower spray gun

[0055] 2 spray gun cores

[0056] 3 Refractory Shell

[0057] 4 Refractory tubular sections

[0058] 5. Refractory Ring Structure

[0059] 5a Semi-circular part

[0060] 5b Semi-circular section

[0061] 6 double groove pins

[0062] 7. Vertical horizontal casting mold

[0063] 8. Reinforced anchoring system

Claims

1. A blower gun (1) for gas injection in a metallurgical process, the blower gun (1) comprising a cylindrical nozzle core (2) and a refractory shell (3). in, The refractory shell (3) includes n+1 refractory tubular parts (4) and n, n+1 or n+2 refractory annular structures (5). In each group, two adjacent refractory tubular sections (4) are separated by a refractory annular structure (5). Where n is an integer of 1 or greater, and The fire-resistant tubular portion (4) is adhered to the cylindrical spray gun core (2) and to the fire-resistant annular structure (5).

2. The blower gun (1) according to claim 1, wherein, The fire-resistant annular structure (5) has an outer diameter corresponding to the outer diameter of the fire-resistant tubular portion (4) and an inner diameter corresponding to the inner diameter of the fire-resistant tubular portion (4).

3. The blower gun (1) according to claim 1 or 2, wherein, Each refractory annular structure (5) is made of the same material as any one of the adjacent refractory tubular portions (4) connected to the refractory annular structure.

4. The blower gun (1) according to claim 1 or 2, wherein, The fire-resistant annular structure (5) and the fire-resistant tubular portion (4) are made of concrete.

5. The blower gun (1) according to claim 1 or 2, wherein, Each of the fire-resistant annular structures (5) is also equipped with a groove pin (6) for fixing the fire-resistant annular structure (5) to the adjacent fire-resistant tubular portion (4).

6. The blower gun (1) according to claim 5, wherein, The slotted pin (6) is made of steel.

7. The blower gun (1) according to claim 5, wherein, The slotted pin (6) is made of stainless steel.

8. The blower gun (1) according to claim 1 or 2, wherein, Each of the refractory annular structures (5) consists of two semi-annular portions (5a, 5b) connected by mortar.

9. The blower gun (1) according to claim 1 or 2, wherein, The first refractory tubular portion (4) is made of a first material, and wherein the second refractory tubular portion (4) is made of a second material different from the first material.

10. The blower gun (1) according to claim 9, wherein, The third refractory tubular portion (4) is made of a third material, which is different from either the first material or the second material.

11. Use of the blower gun (1) according to any one of the preceding claims in gas blowing in a metallurgical process.

12. The use according to claim 11, wherein, The gas injection process mentioned in the metallurgical process is a degassing process.

13. A method for forming a blower gun (1) according to any one of claims 1 to 10, the method comprising the following steps: - Provide a longitudinal horizontal casting mold (7) for casting blower spray guns; - Insert n, n+1, or n+2 refractory ring structures (5) into the longitudinal horizontal casting mold (7); - Insert the cylindrical spray gun core (2) into the longitudinal horizontal casting mold (7) so that the cylindrical spray gun core (2) passes through the central hole of the n, n+1 or n+2 refractory annular structures (5); - Cast n+1 refractory tubular parts (4), wherein each refractory tubular part (4) is separated from the adjacent refractory tubular part (4) by the refractory annular structure (5); - Allows the casting material to solidify; and - Remove the longitudinal horizontal casting mold (7). Where n is an integer of 1 or greater.

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