Preparation method of wear and corrosion resistant coating on roller surface of filter cloth tensioning roller

Abstract

The invention discloses a preparation method of a wear-resistant corrosion-resistant coating on a roller surface of a filter cloth tensioning roller, which comprises the following steps: firstly, cleaning the surface of the filter cloth tensioning roller, and texturing the roller surface by using 46 # white corundum sand; spraying ceramic powder on the roller surface of the filter cloth tensioning roller by adopting plasma spraying equipment to obtain a ceramic coating; a 400 # diamond grinding wheel and a 2000-mesh corundum abrasive belt are adopted to conduct grinding and polishing treatment on the roller face ceramic coating of the filter cloth tensioning roller; the roller surface ceramic coating is subjected to texturing to obtain uniform roughness, and finally, a wear-resistant waterproof film with the thickness of 1-3 microns is prepared on the surface of the roller surface ceramic coating to obtain the filter cloth tensioning roller surface with certain roughness and hardness. According to the method, the defects of surface treatment of the traditional filter cloth tensioning roller are overcome, the bonding strength of the coating and the matrix is high by coating the ceramic coating, and the surface of the filter cloth tensioning roller is endowed with excellent wear resistance and corrosion resistance, so that the online service life of the filter cloth tensioning roller is prolonged, and the water treatment cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of surface treatment engineering, and in particular to a method for preparing a wear and corrosion resistant coating on the surface of a filter cloth tensioning roller. Background Art

[0002] In the industrial water sludge belt dewatering machine for water treatment, filter cloth tensioning rollers are usually used. Since the wastewater contains sludge, sand, salts, and particulate matter, the roller body is severely worn and corroded during industrial wastewater filtration, which affects the service life. At present, flame spraying polytetrafluoroethylene on the roller body surface is adopted to improve the corrosion resistance of the roller surface. Flame spraying polytetrafluoroethylene causes great pollution and is easy to cause harm to the human body. At the same time, polytetrafluoroethylene has low hardness, poor wear resistance, and low bonding strength with the substrate. Generally, after six months of use, the polytetrafluoroethylene coating ages and falls off in a large area, causing scratches on the filter cloth, affecting the filtering effect of industrial wastewater, causing shutdown or frequent replacement, and increasing water treatment costs. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a method for preparing a wear-resistant and corrosion-resistant coating on the surface of a filter cloth tensioning roller. The method overcomes the defects of the surface treatment of traditional filter cloth tensioning rollers. By coating a ceramic coating, the bonding strength between the coating and the substrate is high. At the same time, a layer of wear-resistant and waterproof film is prepared on the surface of the ceramic coating, giving the surface of the filter cloth tensioning roller excellent wear resistance and corrosion resistance, thereby increasing the online service life of the filter cloth tensioning roller and reducing water treatment costs.

[0004] In order to solve the above technical problems, the preparation method of the wear and corrosion resistant coating on the roller surface of the filter cloth tensioning roller of the present invention comprises the following steps: Step 1: Clean the surface of the filter cloth tensioning roller, remove the oil and debris on the roller surface, and blow it dry with compressed air; use 46# white corundum sand, pressure 0.6Mpa, sandblasting distance 250mm, sandblasting angle 90° to roughen the roller surface. After roughening, the roller surface is uniform and has no metallic luster; Step 2: Place the filter cloth tensioning roller after the texturing treatment on the tooling and fix it, and use plasma spraying equipment to spray the roller surface of the filter cloth tensioning roller. The thermal spraying material is ceramic powder, and the particle size of the ceramic powder is 15-53 μm, so that the coating thickness is 150-200 μm. Step 3: Grind and polish the ceramic coating on the roller surface of the filter cloth tensioning roller using a 400# diamond grinding wheel and a 2000-mesh abrasive belt, respectively, and grind and polish the surface coating roughness to Ra0.1-0.2μm to eliminate the surface morphology of the original coating. The coating thickness is 100-150μm; Step 4: Use 180# white corundum sand to roughen the roller surface coating of the filter cloth tensioning roller. The roller surface roughness after roughening is Ra1-1.2μm, and a uniform roughness profile is obtained on the roller surface; Step 5. Prepare a wear-resistant and waterproof film on the surface of the ceramic coating of the filter cloth tensioning roller. Use tetraethyl orthosilicate and n-octyltrimethoxysilane as raw materials, deionized water and anhydrous ethanol as solvents, and ammonia water as catalyst. Mix and stir evenly at room temperature according to the proportion. Use a pneumatic atomizing spray gun with an outlet pressure of 0.1 to 0.2 MPa to evenly spray the surface of the filter cloth tensioning roller. After completion, place it for 24 hours or dry it at 100-120°C for 1 to 2 hours. Finally, a 1 to 3 μm thick wear-resistant and waterproof film is obtained on the surface of the roller coating.

[0005] Furthermore, the ceramic powder is any one of Al2O3-13%TiO2, Al2O3-20%TiO2, Al2O3-40%TiO2, Al2O3-50%TiO2, and Al2O3-Cr2O3.

[0006] Furthermore, the thermal spraying parameters of the plasma spraying equipment are current 500-520A, voltage 60-65V, argon gas flow rate 30-35L / min, spraying distance 100-110mm, powder feeding rate 28-35g / min, and robot spraying 5-6 times. Furthermore, the tetraethyl orthosilicate and n-octyltrimethoxysilane are raw materials, deionized water and anhydrous ethanol are solvents, and ammonia water is a catalyst, and the mass ratio is tetraethyl orthosilicate: n-octyltrimethoxysilane: deionized water: anhydrous ethanol: ammonia water = 10:5:5:50:1.

[0007] Since the preparation method of the wear-resistant and corrosion-resistant coating on the roller surface of the filter cloth tensioning roller of the present invention adopts the above-mentioned technical scheme, that is, the method first cleans the surface of the filter cloth tensioning roller, and uses 46# white corundum sand to roughen the roller surface; uses plasma spraying equipment to spray ceramic powder on the roller surface of the filter cloth tensioning roller to obtain a ceramic coating; uses a 400# diamond grinding wheel and a 2000-mesh corundum abrasive belt to grind and polish the roller surface ceramic coating of the filter cloth tensioning roller respectively, eliminates the original surface morphology of the ceramic coating, and then roughens the roller surface ceramic coating to obtain a uniform roughness, and finally prepares a 1-3μm wear-resistant and waterproof film on the surface of the roller surface ceramic coating, further improves the corrosion resistance of the roller surface coating, and obtains a filter cloth tensioning roller surface with a certain roughness and hardness. The method overcomes the defects of the surface treatment of the traditional filter cloth tensioning roller. By coating the ceramic coating, the bonding strength between the coating and the substrate is high. At the same time, a wear-resistant and waterproof film is prepared on the surface of the ceramic coating, giving the surface of the filter cloth tensioning roller excellent wear resistance and corrosion resistance, so as to increase the online service life of the filter cloth tensioning roller and reduce the water treatment cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments: Figure 1It is a schematic diagram of a method for preparing a wear and corrosion resistant coating on the surface of a filter cloth tensioning roller of the present invention; Figure 2 This is a schematic diagram of the cross-section metallographic structure of the ceramic coating on the filter cloth tensioning roller surface. DETAILED DESCRIPTION

[0009] Implementation example Figure 1 As shown, the method for preparing the wear and corrosion resistant coating on the surface of the filter cloth tensioning roller of the present invention comprises the following steps: Step 1: Clean the surface of the filter cloth tensioning roller, remove the oil and debris on the roller surface, and blow it dry with compressed air; use 46# white corundum sand, pressure 0.6Mpa, sandblasting distance 250mm, sandblasting angle 90° to roughen the roller surface. After roughening, the roller surface is uniform and has no metallic luster; Step 2: Place the filter cloth tensioning roller after the texturing treatment on the tooling and fix it, and use plasma spraying equipment to spray the roller surface of the filter cloth tensioning roller. The thermal spraying material is ceramic powder, and the particle size of the ceramic powder is 15-53 μm, so that the coating thickness is 150-200 μm. Step 3: Grind and polish the ceramic coating on the roller surface of the filter cloth tensioning roller using a 400# diamond grinding wheel and a 2000-mesh abrasive belt, respectively, and grind and polish the surface coating roughness to Ra0.1-0.2μm to eliminate the surface morphology of the original coating. The coating thickness is 100-150μm; Step 4: Use 180# white corundum sand to roughen the roller surface coating of the filter cloth tensioning roller. The roller surface roughness after roughening is Ra1-1.2μm, and a uniform roughness profile is obtained on the roller surface; Step 5. Prepare a wear-resistant and waterproof film on the surface of the ceramic coating of the filter cloth tensioning roller. Use tetraethyl orthosilicate and n-octyltrimethoxysilane as raw materials, water and ethanol as solvents, and ammonia water as catalyst. Mix and stir evenly at room temperature according to the proportion. Use a pneumatic atomizing spray gun with an outlet pressure of 0.1 to 0.2 MPa to evenly spray the surface of the filter cloth tensioning roller. After completion, place it for 24 hours or dry it at 100-120°C for 1 to 2 hours. Finally, a 1 to 3 μm thick wear-resistant and waterproof film is obtained on the roller surface.

[0010] Preferably, the ceramic powder is any one of Al2O3-13%TiO2, Al2O3-20%TiO2, Al2O3-40%TiO2, Al2O3-50%TiO2, and Al2O3-Cr2O3.

[0011] Preferably, the thermal spraying parameters of the plasma spraying equipment are current 500-520A, voltage 60-65V, argon gas flow rate 30-35L / min, spraying distance 100-110mm, powder feeding rate 28-35g / min, and robot spraying 5-6 times.

[0012] Preferably, the tetraethyl orthosilicate and n-octyltrimethoxysilane are raw materials, deionized water and anhydrous ethanol are solvents, and ammonia water is a catalyst, and the mass ratio is tetraethyl orthosilicate: n-octyltrimethoxysilane: deionized water: anhydrous ethanol: ammonia water = 10:5:5:50:1.

[0013] Alumina-based ceramic materials have excellent wear resistance and corrosion resistance, and have been widely promoted and applied in the field of surface treatment engineering; plasma spraying technology has a high flame temperature and can spray a variety of spraying materials, especially refractory materials with high melting points, such as refractory metals, ceramics, metal ceramics and other special functional materials, and are widely used to improve the special functions of material surfaces.

[0014] This method uses plasma spraying equipment to prepare a ceramic coating on the surface of the filter cloth tensioning roller by spraying any one of Al2O3-13%TiO2, Al2O3-20%TiO2, Al2O3-40%TiO2, Al2O3-50%TiO2, and Al2O3-Cr2O3 ceramic powders with a powder particle size of 15 to 53 μm. Figure 2 As shown, the filter cloth tensioning roller substrate 3 is any one of carbon steel, stainless steel, and low alloy steel. The coating 2 has a high bonding strength with the substrate 3, which gives the surface of the filter cloth tensioning roller excellent wear resistance and corrosion resistance, thereby improving the online service life of the filter cloth tensioning roller. By controlling the spraying of alumina ceramic powder to a ceramic coating thickness of 150 to 200 μm, the original surface morphology of the ceramic coating is eliminated through grinding and polishing, and then the ceramic coating on the roller surface is roughened to obtain a uniform roughness. Finally, a 1 to 3 μm wear-resistant and waterproof film is prepared on the surface of the roller surface ceramic coating to further improve the corrosion resistance of the roller surface coating. Coating performance: coating hardness HRC ≥ 60, and the bonding strength between the coating and the substrate ≥ 50Mpa. The process of this method is simple to implement, the processing process is green and environmentally friendly, the product service life is extended by more than 3 times, and the prepared ceramic coating gives the filter cloth tensioning roller excellent wear resistance and corrosion resistance.

Claims

1. A method for preparing a wear and corrosion resistant coating on the surface of a filter cloth tensioning roller, characterized in that The steps include: Step 1: Clean the surface of the filter cloth tensioning roller, remove the oil and debris on the roller surface, and blow it dry with compressed air; use 46# white corundum sand, pressure 0.6Mpa, sandblasting distance 250mm, sandblasting angle 90° to roughen the roller surface. After roughening, the roller surface is uniform and has no metallic luster; Step 2: Place the filter cloth tensioning roller after the texturing treatment on the tooling and fix it, and use plasma spraying equipment to spray the roller surface of the filter cloth tensioning roller. The thermal spraying material is ceramic powder, and the particle size of the ceramic powder is 15-53 μm, so that the coating thickness is 150-200 μm. Step 3: Grind and polish the ceramic coating on the roller surface of the filter cloth tensioning roller using a 400# diamond grinding wheel and a 2000-mesh abrasive belt, respectively, and grind and polish the surface coating roughness to Ra0.1-0.2μm to eliminate the surface morphology of the original coating. The coating thickness is 100-150μm; Step 4: Use 180# white corundum sand to roughen the roller surface coating of the filter cloth tensioning roller. The roller surface roughness after roughening is Ra1-1.2μm, and a uniform roughness profile is obtained on the roller surface; Step 5. Prepare a wear-resistant and waterproof film on the surface of the ceramic coating of the filter cloth tensioning roller. Use tetraethyl orthosilicate and n-octyltrimethoxysilane as raw materials, deionized water and anhydrous ethanol as solvents, and ammonia water as a catalyst. Mix and stir evenly at room temperature according to the proportion. Use a pneumatic atomizing spray gun with an outlet pressure of 0.1 to 0.2 MPa to evenly spray the surface of the filter cloth tensioning roller. After completion, place it for 24 hours or dry it at 100 to 120°C for 1 to 2 hours. Finally, a 1 to 3 μm thick wear-resistant and waterproof film is obtained on the surface of the roller coating.

2. The method for preparing the wear and corrosion resistant coating on the surface of the filter cloth tensioning roller according to claim 1, characterized in that: The ceramic powder is any one of Al2O3-13%TiO2, Al2O3-20%TiO2, Al2O3-40%TiO2, Al2O3-50%TiO2, and Al2O3-Cr2O3.

3. The method for preparing the wear and corrosion resistant coating on the surface of the filter cloth tensioning roller according to claim 1 or 2, characterized in that: The thermal spraying parameters of the plasma spraying equipment are current 500-520A, voltage 60-65V, argon gas flow rate 30-35L / min, spraying distance 100-110mm, powder feeding rate 28-35g / min, and robot spraying 5-6 times.

4. The method for preparing the wear and corrosion resistant coating on the surface of the filter cloth tensioning roller according to claim 1, characterized in that: The wear-resistant and waterproof film is prepared on the surface of the ceramic coating, with tetraethyl orthosilicate and n-octyltrimethoxysilane as raw materials, deionized water and anhydrous ethanol as solvents, and ammonia water as a catalyst, and the mass ratio of tetraethyl orthosilicate: n-octyltrimethoxysilane: deionized water: anhydrous ethanol: ammonia water = 10:5:5:50:1.

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