Anticorrosion treatment method for metal material

Abstract

The invention is suitable for the technical field of material corrosion prevention, and particularly relates to an anti-corrosion treatment method for a metal material, and the method comprises the following steps: blanking an anti-corrosion layer, carrying out trepanning treatment on the blanked anti-corrosion layer, and marking a welding position; the base material plate is subjected to blanking, the base material plate obtained through blanking is subjected to trepanning treatment, and hole sites between the anti-corrosion layer and the base material plate correspond to each other; plug welding treatment is conducted on the holes in the base material plate through an anti-corrosion material; and the base material plate is subjected to pasting treatment through the anti-corrosion layer. According to the anti-corrosion treatment method for the metal material, the anti-corrosion layer is attached to the base material plate, the corrosion problem of the corroded face can be well solved, the service life of equipment is greatly prolonged, the corrosion resistance is improved by 2-3 times compared with a traditional mode of coating glass flakes and using weathering steel, and the service life of the equipment is prolonged by 3-5 years; and the manufacturing cost is low.

Description

Technical Field

[0001] The present invention belongs to the technical field of material anti-corrosion, and particularly relates to an anti-corrosion treatment method for metal materials. Background Art

[0002] In actual work, due to the complex working environment, there are various corrosive substances in the flue gas. Especially during the desulfurization and purification of various flue gas dusts, sulfur dioxide gas therein will produce sulfuric acid under certain conditions, and sulfuric acid has extremely strong corrosiveness. When the rotary heat exchanger conducts heat exchange on the flue gas, the flue gas at the cold end forms a dew point due to the low temperature. It will cause certain corrosion to the steel equipment and devices, and finally produce sulfates. More importantly, these substances will cause relatively serious corrosion to the lining part of the desulfurization and denitration equipment.

[0003] Traditional anti-corrosion technologies adopt two methods: one is to coat enamel on the corroded surface. In principle, this method can isolate the corrosion of the acid solution to the base material, but there are two problems in the actual application process. The bonding force between the surface enamel and the base material is insufficient, resulting in the enamel peeling off; the enamel surface is brittle, and under external force or thermal deformation, the enamel layer peels off. After the enamel peels off, the base material is easily corroded and will also corrode from the inside to the non-peeled enamel area. The other is to use weathering steel with corrosion resistance on the corroded surface. At present, the corrosion resistance of weathering steel is average. Weathering steel, that is, atmospheric corrosion-resistant steel, is a series of low-alloy steels between ordinary steel and stainless steel. Weathering steel is made by adding a small amount of corrosion-resistant elements such as copper and nickel to plain carbon steel, and has the characteristics of high-quality steel such as toughness, plasticity, formability, welding and cutting, abrasion resistance, high temperature resistance, and fatigue resistance; the weather resistance is 2 to 8 times that of plain carbon steel. At present, the corrosion resistance of weathering steel in a high-acid environment also cannot meet the on-site requirements. The corrosion resistance of stainless steel is relatively good and can basically meet the current working conditions requirements, but the mechanical properties of stainless steel cannot meet the overall strength requirements, and at the same time, the cost of duplex stainless steel is also relatively high. Summary of the Invention

[0004] The purpose of the present invention is to provide an anti-corrosion treatment method for metal materials, aiming to solve the problems that the mechanical properties of stainless steel cannot meet the overall strength requirements and the cost of duplex stainless steel is relatively high.

[0005] The present invention is implemented as follows. An anti-corrosion treatment method for metal materials, the method includes:

[0006] Cut the anti-corrosion layer, perform hole-opening treatment on the cut anti-corrosion layer, and mark the welding positions;

[0007] Cut the base material plate, perform hole-opening treatment on the cut base material plate, and the hole positions between the anti-corrosion layer and the base material plate correspond to each other;

[0008] Plug weld the holes on the base plate with anticorrosive materials;

[0009] Apply the anticorrosive layer to the base plate.

[0010] Preferably, in the steps of cutting the anticorrosive layer, making holes in the cut anticorrosive layer, and marking the welding positions, when cutting the anticorrosive layer, laser cutting is used, and the surface flatness meets the preset requirements.

[0011] Preferably, in the steps of cutting the anticorrosive layer, making holes in the cut anticorrosive layer, and marking the welding positions, the diameter of the holes made in the anticorrosive layer is larger than the diameter of the holes made in the base plate, and the difference between the two is a preset value.

[0012] Preferably, the base plate is cut by laser, and the tolerance of the hole position and hole diameter is within ±0.1 mm.

[0013] Preferably, in the step of plug welding the holes on the base plate with anticorrosive materials, stainless steel pipes are placed in the holes, and then plug welding is carried out. The difference between the outer diameter of the stainless steel pipes and the inner diameter of the holes on the base plate is a preset value.

[0014] Preferably, if the anticorrosive layer needs to be bent, the right-angle bend R of the anticorrosive layer is less than 1 mm.

[0015] Preferably, in the step of applying the anticorrosive layer to the base plate, a strong magnetic adsorption anticorrosive layer is used for positioning, and the anticorrosive layer is welded to the base plate by butt welding, and the welding position is sealed by welding.

[0016] Preferably, anti-bending flat steel is provided on the base plate. The anti-bending flat steel is bent into a U-shaped structure by the anticorrosive layer for coating, fixed to the base plate by butt welding, and the edge is sealed by sealed welding.

[0017] The anticorrosion treatment method for metal materials provided by the present invention can well solve the corrosion problem of the corroded surface by applying an anticorrosive layer on the base plate, greatly extend the service life of the equipment, improve the corrosion resistance by 2-3 times compared with the traditional methods of applying glass flakes and using weathering steel, extend the service life of the equipment by 3-5 years, and has low manufacturing cost. Description of the Drawings

[0018] Figure 1 It is a schematic diagram of the solder joint arrangement of butt welding provided by an embodiment of the present invention;

[0019] Figure 2 It is a schematic diagram of the bending angle provided by an embodiment of the present invention;

[0020] Figure 3A first schematic diagram of the anti-corrosion layer welding provided by an embodiment of the present invention;

[0021] Figure 4 A second schematic diagram of the anti-corrosion layer welding provided by an embodiment of the present invention;

[0022] Figure 5 A third schematic diagram of anti-corrosion layer welding provided by an embodiment of the present invention;

[0023] Figure 6 A schematic diagram of the welding of the anti-corrosion layer at the anti-bending flat steel provided in an embodiment of the present invention;

[0024] Figure 7 A schematic diagram of installing a stainless steel pipe at a hole provided by an embodiment of the present invention;

[0025] Figure 8 A flowchart of an anti-corrosion treatment method for metal materials provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0027] The specific implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0028] like Figure 1 , Figure 8 and Figure 6 As shown, an anti-corrosion treatment method for metal materials provided by an embodiment of the present invention comprises:

[0029] Cut the anti-corrosion layer, perform hole processing on the anti-corrosion layer obtained by cutting, and mark the welding position.

[0030] In this step, laser cutting is required for cutting the anti-corrosion layer. The cut surface should be smooth and flat without oxide scale (nitrogen cutting is recommended). The surface of the anti-corrosion layer should be kept clean and tidy without dust, oil stains, etc. The surface of the cut anti-corrosion layer should be flat and meet the requirements of the national standard "Steel Plate Flatness" (GB / T 709-2006). There should be no dead bends, and no pits or protrusions on the surface. The cut anti-corrosion layer needs to be coded and marked, and the identification number needs to correspond to the compartment number of the veneer. The cut anti-corrosion layer parts need to be marked with lines to mark the butt welding position. The cutting size of the anti-corrosion layer should be measured on site according to the completed welded compartment. The hole diameter of the anti-corrosion layer should be 0.5mm larger than the hole diameter on the substrate plate.

[0031] Cut the base material board, and perform hole-opening treatment on the cut base material board. The hole positions between the anti-corrosion layer and the base material board correspond to each other.

[0032] In this step, the base material board uses Q235B, and laser cutting is used for cutting the base material board to ensure that the hole position and hole diameter tolerance are within ±0.1 mm. The surface of the base material that needs to be covered with skin needs to be kept clean and tidy, without dust, oil stains, and oxide scales. The base material board should be corrected and flattened to meet the requirements of the national standard "Flatness of Steel Plates" (GB / T 709 - 2006), without dead bends, and there should be no pits and protrusions on the surface. The surface of the base material should reach above grade B, and the area that needs to be covered with skin should be marked with position numbers, and the position numbers need to be consistent with the position numbers of the stainless steel plate parts to be covered.

[0033] Use anti-corrosion materials to perform plug welding on the holes on the base material board.

[0034] In this step, as Figure 2 shown, the holes on the base material board need to be plug welded with stainless steel pipes of the same material and wall thickness. The outer diameter of the stainless steel pipe should be 0.2 mm smaller than the hole on the base material board.

[0035] Perform coating treatment on the base material board through the anti-corrosion layer.

[0036] In this step, according to the actual measured values of the bin compartments on-site, cut the materials. The cutting size width is the inner size of two transverse partitions - the width of two fillet welds, and the length direction is the required skin-covering height - the fillet weld size of the anti-bending flat steel. The bin compartment skin-covering adopts a vertical installation mode. Before skin-covering, it is necessary to check the bin compartment skin-covering area to ensure that the area is clean and tidy, without oxide scales, dust, or oil stains. The stainless steel plate that needs to be covered with skin is positioned by strong magnetic adsorption, and butt welding is carried out from the inside out according to the butt welding points marked during cutting. The welding uses 150KW high-power butt welding, and the single-point welding duration is 5 seconds. The diameter of the fusion core of the weld point is not less than 7 mm. Before welding, it is necessary to ensure that the skin-covering stainless steel is closely fitted with the base material without gaps. After welding, the shear force of the butt welding points is not less than 12.8 KN. The edge of the anti-corrosion layer (2205 duplex stainless steel) uses a laser welding machine with a power of more than 3000W, and the wire filling method is adopted. The welding method at the fillet weld lap joint and the welding method at the lap joint between the anti-corrosion layer and the radial plate are shown in Figure 3 Figure 4 and Figure 5 , anti-bending flat steel is set on the base material board. The skin-covering at the anti-bending flat steel uses the method of bending the outer anti-corrosion layer into a "U" - shaped groove, and the fillet weld is sealed and welded using laser welding. The center position on the side is fixed by butt welding at intervals of 100 mm. See Figure 6 for details. The fastening bolt holes of the radial partition sealing piece adopt the plugging method with 2205 stainless steel pipes (i.e., steel pipes of the same material as the anti-corrosion layer). The stainless steel pipe is sealed and welded with the skin-covering stainless steel plate. The edge of the skin-covering stainless steel plate is sealed and welded using laser welding. See Figure 7 for details.

[0037] After the cladding is completed, perform PT inspection on the sealed and welded cold wind to ensure that the welds are defect-free.

[0038] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for anti-corrosion treatment of metal materials, characterized in that, The method includes: Cut the anticorrosion layer, perform hole-opening treatment on the cut anticorrosion layer, and mark the welding positions; Cut the base material plate, perform hole-opening treatment on the cut base material plate, and the hole positions between the anticorrosion layer and the base material plate correspond to each other; Perform plug welding treatment on the holes on the base material plate with anticorrosion materials; Perform pasting treatment on the base material plate through the anticorrosion layer.

2. The anti-corrosion treatment method for metal materials according to claim 1, wherein In the step of cutting the anticorrosion layer, performing hole-opening treatment on the cut anticorrosion layer, and marking the welding positions, when cutting the anticorrosion layer, laser cutting is used, and the surface flatness meets the preset requirements.

3. The anti-corrosion treatment method for metallic materials according to claim 1, characterized in that, In the step of cutting the anticorrosion layer, performing hole-opening treatment on the cut anticorrosion layer, and marking the welding positions, the diameter of the holes opened on the anticorrosion layer is larger than the diameter of the holes opened on the base material plate, and the difference between the two is a preset value.

4. The anti-corrosion treatment method for metal materials according to claim 1, characterized in that, The base material plate is cut by laser, and the tolerance of the hole position and the hole diameter is within ±0.1 mm.

5. The anti-corrosion treatment method for metal materials according to claim 1, characterized in that, In the step of performing plug welding treatment on the holes on the base material plate with anticorrosion materials, stainless steel pipes are inserted into the holes, and then plug welding treatment is performed. The difference between the outer diameter of the stainless steel pipes and the inner diameter of the holes on the base material plate is a preset value.

6. The anti-corrosion treatment method for metallic materials according to claim 1, characterized in that, If the anticorrosion layer needs to be bent, the right-angle bend R of the anticorrosion layer is less than 1 mm.

7. The anti-corrosion treatment method for metallic materials according to claim 1, characterized in that, In the step of performing pasting treatment on the base material plate through the anticorrosion layer, a strong magnetic adsorption anticorrosion layer is used for positioning, the anticorrosion layer is welded to the base material plate by the butt welding method, and the welding positions are sealed by welding.

8. The anti-corrosion treatment method for metal materials according to claim 1, characterized in that, The base material plate is provided with anti-bending flat steel, and the anti-bending flat steel is bent into a U-shaped structure through the anticorrosion layer for coating, fixed on the base material plate by butt welding, and the edge is sealed by sealing welding.

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