Weldless anti-friction and anti-deformation coal injection gun with reduced resistance

Abstract

This utility model discloses a seamless, drag-reducing, wear-resistant, and deformation-resistant coal injection gun with a seamless nozzle body, comprising a nozzle tube (1) and a deformation-resistant sleeve (2). The nozzle tube (1) is made of seamless 310S or 314 stainless steel pipe with no welds, and is partially lined with alumina ceramic (3); the alumina ceramic (3) has a thickness of 1-3mm at the head and a flared shape at the tail with the thickness gradually decreasing to 0, and the lining length is 10%-50% of the pipe length. The deformation-resistant sleeve (2) is composed of multiple sections of 314 or 310S stainless steel, with the first section argon-arc welded and fixed to the nozzle tube (1), and the remaining sections connected by a central plug weld. This utility model avoids weld cracking, and has drag reduction, wear resistance, and deformation-resistant functions, improving the service life and stability of the coal injection gun, and is suitable for coal injection operations in industries such as metallurgy and ironmaking.

Description

Technical Field

[0001] This utility model relates to a coal injection gun, and more particularly to a coal injection gun with a seamless nozzle body, reduced drag, wear resistance and anti-deformation function, which is mainly used in coal injection operations in industries such as metallurgy and ironmaking. Background Technology

[0002] In existing technologies, coal injection guns often face problems such as wear, high resistance, and easy deformation during use. Traditional coal injection guns solve the problems of weld cracking, easy wear, and high conveying resistance by using a seamless Al2O3 ceramic layer as a partial inner lining of the main body of the injection gun tube. However, during operation, the coal injection gun is prone to deformation due to factors such as thermal stress and coal dust impact. To prevent deformation from eroding the tuyeres sleeve, frequent gun adjustments are necessary, leading to problems such as peeling off of the alumina ceramic layer and damage to the coal injection gun, reducing production efficiency and equipment stability. In recent years, anti-deformation coal injection guns have also begun to be used, but due to the segmented welding process, they have led to weld cracking, increased conveying resistance, frequent gun blockage, and severe burn-out of the coal injection gun. To solve these problems simultaneously, we designed a seamless, drag-reducing, wear-resistant, and deformation-resistant coal injection gun with a seamless main body of the injection gun tube. Summary of the Invention

[0003] (I) Purpose of the utility model

[0004] The purpose of this utility model is to provide a coal injection gun with a seamless, drag-reducing, wear-resistant, and deformation-resistant nozzle body, in order to solve the problems of weld cracking, easy wear, high resistance, and easy deformation of existing coal injection guns, and improve the service life, working efficiency, and stability of the coal injection gun.

[0005] (II) Technical Solution

[0006] To achieve the above objectives, the present invention adopts the following solution:

[0007] 1. Spray Gun Tube: The spray gun tube is made of a seamless 310S (or 314) stainless steel pipe without welds. This fundamentally avoids problems such as cracking and leakage that may occur at welds. Furthermore, it employs a self-propagating localized alumina ceramic lining process. The thickness of the alumina ceramic layer at the head is selected between 1 and 3.5 mm according to the diameter requirements of the pulverized coal gun. The tail end is a naturally formed flared opening during processing, and the alumina ceramic thickness gradually decreases to 0 within the lining length, which is 10%-50% of the total length of the spray gun tube. This design solves the problem of easy wear of the spray gun tube and effectively reduces the resistance of pulverized coal conveying.

[0008] 2. Anti-deformation sleeve; the anti-deformation sleeve is made of 314 (or 310S) stainless steel and consists of multiple sections. The first section is fixed to the corresponding position on the spray gun pipe using argon arc welding at one end to prevent it from shifting forward and altering the coal flow. The remaining sections are fixed to the spray gun pipe with only one plug weld in the middle. This connection method ensures free expansion and contraction of the spray gun pipe when heated, preventing the anti-deformation sleeve from being thinned or cracked, thus effectively preventing deformation of the coal injection gun.

[0009] (III) Beneficial Effects

[0010] Compared with the prior art, the present invention has the following significant advantages:

[0011] 1. Seamless Advantage: The spray gun tube adopts a seamless design, which completely avoids damage caused by high temperature, coal dust erosion and other factors at the weld seam, greatly improving the reliability and service life of the coal spray gun.

[0012] 2. Drag Reduction and Wear Resistance: The alumina ceramic lining significantly enhances the wear resistance of key wear areas of the spray gun tube; at the same time, the special flared and gradually thickened design of the alumina ceramic tail effectively reduces the resistance of coal powder transportation and improves coal injection efficiency.

[0013] 3. Anti-deformation function: The multi-section design of the anti-deformation sleeve and its special connection method (the first section is fixed by argon arc welding, and the rest are single-point plug welding) enable the coal injection gun to effectively adapt to thermal expansion during operation, resist the overall deformation caused by thermal stress and other factors, ensure the stability of the coal injection gun and the uniformity of coal injection, and reduce the frequency of gun adjustment and the damage caused therefrom. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of the weldless, drag-reducing, wear-resistant, and deformation-resistant coal injection gun of this utility model.

[0015] In the picture: 1. Spray gun pipe (single section, seamless), 2. Anti-deformation sleeve (multi-section), 3. Alumina ceramic Detailed Implementation

[0016] The implementation of this utility model will be described in further detail below with reference to the technical solution:

[0017] 1. Spray gun pipe fabrication: Select high-quality 310S (or 314) stainless steel seamless pipe and choose the inner and outer diameters of the spray gun pipe according to the requirements of the pulverized coal gun. Cut a section according to the length requirements of the pulverized coal gun (ensuring no weld seams). Then, use the self-propagating high-temperature synthesis (SHS) process to line the inner wall of the spray gun pipe with alumina ceramic in specific areas (the blowing end and easily worn sections). Strictly control the process parameters to ensure that the alumina ceramic reaches the required thickness at the head (blowing end) (1-3.5mm, selected according to the diameter requirements of the pulverized coal gun), and naturally forms a flared transition at the tail end. The thickness of the alumina ceramic gradually changes uniformly to 0mm within the lining area. The lining length should be controlled within the range of 10%-50% of the total length of the spray gun pipe.

[0018] 2. Fabrication and Installation of Anti-deformation Sleeves: 314 (or 310S) stainless steel pipes are processed into multiple sleeve sections (the number of sections is determined based on the length of the spray gun pipe and anti-deformation requirements). First, the head end of the first anti-deformation sleeve section is firmly fixed to a predetermined position on the outer wall of the spray gun pipe (usually near the injection end) using argon arc welding. This welding primarily prevents the anti-deformation sleeve from shifting forward during use. Then, the remaining anti-deformation sleeve sections are sequentially fitted onto the spray gun pipe, with each section only connected to the outer wall of the spray gun pipe via a plug weld at its very center. The number of plug welds is strictly limited to one per section. This connection method ensures a secure connection between the sleeve sections, while allowing for a small gap or slight expansion / contraction between the sleeve sections when the spray gun pipe expands axially due to heat. This allows the anti-deformation sleeve as a whole to freely expand and contract with the thermal expansion and contraction of the spray gun pipe, preventing the anti-deformation sleeve itself from being thinned or cracked, thus effectively suppressing the bending deformation of the coal injection gun.

Claims

1. A no-weld seam, drag-reducing, wear-resistant, and deformation-resistant coal injection lance with a lance tube body, characterized in that, Includes the spray gun barrel (1) and the anti-deformation sleeve (2): The spray gun tube (1) is made of a section of seamless 310S or 314 stainless steel tube without welds, and the stainless steel seamless tube is partially lined with alumina ceramic (3). The thickness of the head of the alumina ceramic (3) is selected from 1 to 3.5 mm according to the requirements of the pulverized coal gun diameter. The tail naturally forms a flared mouth during the preparation of the alumina ceramic (3). The thickness of the alumina ceramic (3) gradually decreases to 0 within the range of the inner lining length. The inner lining length is 10% to 50% of the total length of the pulverized coal gun pipe. The anti-deformation sleeve (2) is composed of multiple sections made of 314 or 310S stainless steel; The first section of the anti-deformation sleeve (2) is fixed to the corresponding position of the spray gun tube (1) by argon arc welding, and the remaining sections are fixed to the spray gun tube (1) by a plug weld.

2. The seamless drag reducing abrasion resistant deformation resistant millimeter coal injection lance according to claim 1, wherein, The axial spacing between each section of the anti-deformation sleeve (2) is 0-10mm.

3. The seamless drag reducing abrasion resistant deformation resistant millimeter coal injection lance according to claim 1 or 2, characterized in that, The number of plug welds on each of the remaining sections of the anti-deformation sleeve (2) is only one, and it is placed in the exact center of each anti-deformation sleeve (2).

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