Method and device for removing oxidation film on surface of tin coating of strip steel

Abstract

The invention relates to a method and device for removing an oxidation film on the surface of a tin coating of strip steel, and the method comprises the following steps: arranging a pretreatment working tank after the strip steel is subjected to soft melting treatment; an electrode plate is arranged in the pretreatment working tank, a conductive roller is arranged above the pretreatment working tank, and the pretreatment working tank is filled with a Na2CO3 working solution; strip steel is located between the two sets of symmetrically-arranged electrode plates, and the conductive rollers make contact with the strip steel and conduct current. The electrode plate is connected with a positive electrode of a power supply, the conductive roller is connected with a negative electrode of the power supply, an electrolysis loop is formed by taking the strip steel as a negative electrode, the electrode plate as a positive electrode and a Na2CO3 solution as a working solution in the pretreatment working tank, and an oxidation film on the surface of a tin coating of the strip steel is subjected to electrochemical reaction to be removed through alkalescence electrolysis treatment. The invention further provides a device for removing the oxidation film on the surface of the strip steel tin coating, and the device is used for achieving the method.

Description

Technical Field

[0001] This invention relates to continuous electroplating technology for strip steel in the metallurgical industry, and in particular to a method and apparatus for removing the oxide film on the surface of the tin-plated layer of strip steel in a continuous tin-chromium electroplating production line. Background Technology

[0002] Tinplate holds an important position in the food and beverage can market, but due to the scarcity of tin resources, its price has continued to rise, leading to a continuous increase in production costs. Furthermore, tinplate suffers from insufficient printability: the tin layer easily melts when the baking temperature is too high, and the ink is prone to peeling off during machining and high-temperature sterilization.

[0003] Tin-chromium ferrochrome (TFS), an emerging product in the tinplate industry, is widely used in food packaging such as beverage cans and milk powder cans. This material combines the high adhesion and excellent printability of chrome-plated sheets with the good solderability of tin-plated sheets by depositing an extremely thin layer of metallic chromium on a low-tin-content tinplate sheet, completely avoiding the problem of molten tin, supporting higher baking temperatures, and significantly improving printing and coating production efficiency. However, in continuous tin-chromium electroplating production lines for strip steel (commonly known as "tin-chromium ferrochrome" or "tinplate"), the tin plating layer of the tin-plated strip steel is heated from room temperature to a molten temperature of 232°C during the remelting process. Therefore, the surface of the strip steel after remelting is mostly composed of tin oxide (SnO) film. Long-term storage in air with a certain humidity will cause oxidation to produce tin dioxide (SnO2), and this tin-containing oxide film will interfere with subsequent chromium electroplating processes. Due to the extremely thin film, how to completely remove the oxide film while avoiding damage to the tin plating layer has become a pressing technical problem to be solved in this field. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method and apparatus for removing the oxide film on the surface of tin-plated steel strip, which addresses the above-mentioned deficiencies of the prior art.

[0005] To achieve the above objectives, the present invention provides a method for removing the oxide film from the surface of a tin-plated steel strip, wherein the method is used in a continuous tin-chromium electroplating production line for steel strip and includes the following steps:

[0006] After the strip steel softening process, a pretreatment working tank is set up;

[0007] Electrode plates are installed in the pretreatment working tank, and conductive rollers are installed above the pretreatment working tank, which is filled with Na2CO3 working solution; the strip steel is located between two sets of symmetrically arranged electrode plates, and the conductive rollers are in contact with the strip steel and conduct current.

[0008] The electrode plate is connected to the positive terminal of the power supply, and the conductive roller is connected to the negative terminal of the power supply. In the pretreatment working tank, the strip steel is used as the cathode, the electrode plate is used as the anode, and Na2CO3 solution is used as the working fluid to form an electrolytic circuit. Through weak alkaline electrolytic treatment, the oxide film on the surface of the tin-plated layer of the strip steel undergoes an electrochemical reaction and is removed.

[0009] In the above-mentioned method for removing the oxide film on the surface of the tin-plated layer of the strip steel, the electrode plate uses a pure titanium plate as the substrate, and the discharge surface of the pure titanium plate facing the strip steel and the conductive contact surface are both coated with a platinum layer. The current is conducted to the discharge surface of the electrode plate through evenly distributed conductive bolts.

[0010] The above-mentioned method for removing the oxide film on the surface of the tin-plated steel strip also includes, after the oxide film on the surface of the tin-plated steel strip is removed, the steel strip is directly put into a spray tank for rinsing, and after rinsing, it is put into a tin-chromium-iron working tank to complete the surface chromium plating process.

[0011] In the above-described method for removing the oxide film from the surface of the tin-plated steel strip, the electrode plate includes a conductive plate, a discharge plate, and a copper busbar. An insulating plate is disposed between the conductive plate and the discharge plate. The conductive plate is connected to the copper busbar, and the copper busbar is connected to the anode of the power supply.

[0012] In the above-described method for removing the oxide film from the surface of the tin-plated steel strip, the area of ​​the discharge plate is smaller than the area of ​​the conductive plate, and the area of ​​the insulating plate is equal to the area of ​​the discharge plate.

[0013] In the above-described method for removing the oxide film from the surface of the tin-plated steel strip, a fluid channel is provided on the electrode plate. The fluid channel consists of multiple through holes of a set diameter in the assembly composed of the conductive plate, the discharge plate, and the insulating plate, which enhances the fluidity of the working fluid to optimize the reaction efficiency.

[0014] In the above-mentioned method for removing the oxide film on the surface of the tin-plated steel strip, the copper busbar is made of T2 copper, the conductive plate is made of TA2 pure titanium, the discharge plate is made of TA2 pure titanium, and a 3-5.3 micrometer platinum layer is plated on the working surface of the steel strip. The insulating plate is made of alkali-resistant fiberglass.

[0015] In the above-described method for removing the oxide film from the surface of the tin-plated steel strip, the conductive bolt is a titanium alloy bolt.

[0016] In the above-described method for removing the oxide film from the surface of the tin-plated steel strip, the conductive contact surface includes the connection contact surface between the copper busbar and the electrode plate, and the energized contact surface between the conductive bolt and the washer.

[0017] To better achieve the above objectives, the present invention also provides an apparatus for removing the oxide film on the surface of the tin-plated layer of steel strip, wherein the method for removing the oxide film on the surface of the tin-plated layer of steel strip is described above.

[0018] The technical effects of this invention are as follows:

[0019] This invention is specifically designed to remove the oxide film from the surface of tin-plated steel strips, effectively solving the problem of incomplete removal of the oxide film in existing technologies. While effectively removing the oxide film, it ensures that the tin plating itself remains undamaged. Its electrode plate employs a titanium substrate with a platinum plating structure. The titanium substrate provides excellent mechanical strength and corrosion resistance, ensuring electrode structural stability. The high inertness and catalytic activity of the platinum plating ensure long-term stability and efficiency of the electrode surface. As the core conductive layer, it provides an extremely low-resistance current path, ensuring efficient current transmission to the reaction interface. It effectively protects the titanium substrate, preventing the formation of a high-resistance oxide film during anodic operation and subsequent passivation failure. The use of evenly distributed titanium alloy bolts optimizes the balance between conductivity, mechanical stability, and corrosion resistance. The evenly distributed bolts disperse installation stress, preventing substrate deformation and cracking of the brittle platinum plating. The titanium alloy bolts have a similar potential to the pure titanium substrate, making them less prone to galvanic corrosion in the electrolyte, thus preventing damage to the bolts and substrate. Corrosion at the edges of mounting holes; titanium alloys remain passivated in alkaline working solutions, ensuring long-term service without rust or electrolyte contamination; using weakly alkaline solutions such as Na+ and K+ carbonates effectively removes the oxide film on the tin plating surface through the strong mechanical peeling force generated by electrochemical hydrogen evolution and alkaline saponification, thus ensuring excellent adhesion and uniformity of the plating layer; the solution is mild, has pH buffering capacity, is easy to maintain, causes minimal damage to the substrate and equipment, and minimizes corrosion of the tin plating itself; the solution itself is non-toxic, and subsequent wastewater treatment is simple, further demonstrating its dual advantages in environmental protection and economy. Therefore, using weakly alkaline electrolytes is a reliable and comprehensive standard cleaning solution that has been proven through long-term practice.

[0020] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the present invention. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the device structure according to an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of an electrode plate structure according to an embodiment of the present invention;

[0023] Figure 3 This is a cross-sectional view of an electrode plate according to an embodiment of the present invention;

[0024] Figure 4 for Figure 3 Enlarged view of part A;

[0025] Figure 5 for Figure 3 Enlarged view of part B.

[0026] Among them, the attached reference numerals

[0027] 1. Body

[0028] 2 Pretreatment working tank

[0029] 3 Submerged Rollers

[0030] 4 Electrode plates

[0031] 41 Copper busbars

[0032] 42 conductive plate

[0033] 43 Discharge Plate

[0034] 44 Conductive Bolt

[0035] 45 Insulation Board

[0036] 46 Conductive pads

[0037] 47 Locking nut

[0038] 48 Fluid Channels

[0039] 5 conductive rollers

[0040] 6. Steel strip Detailed Implementation

[0041] The structural and working principles of the present invention will be described in detail below with reference to the accompanying drawings:

[0042] See Figure 1 , Figure 1 This is a schematic diagram of the device structure according to an embodiment of the present invention. The device for removing the oxide film on the surface of the tin-plated layer of steel strip of the present invention is used to realize the following method for removing the oxide film on the surface of the tin-plated layer of steel strip, including a machine body 1 and a pretreatment working tank 2, a submerged roller 3 and a conductive roller 5 disposed on the machine body 1. The pretreatment working tank 2 is used to contain the working liquid and the electrode plate 4. The submerged roller 3 is located at the bottom of the machine body 1, and the conductive roller 5 is located above the machine body 1. The electrode plate 4 is disposed in the pretreatment working tank 2 and filled with Na2CO3 working liquid. The steel strip 6 is located between two sets of symmetrically arranged electrode plates 4. The conductive roller 5 contacts the steel strip 6 to conduct cathode current. The electrode plate 4 is connected to the positive terminal of the power supply, and the conductive roller 5 is connected to the negative terminal of the power supply. In the pretreatment working tank 2, the steel strip 6 is used as the cathode, the electrode plate 4 is used as the anode, and the Na2CO3 solution is used as the working liquid to form an electrolytic circuit. Through weak alkaline electrolytic treatment, the oxide film on the surface of the tin-plated layer of the steel strip undergoes an electrochemical reaction and is removed.

[0043] See Figures 2-5 , Figure 2 This is a schematic diagram of the electrode plate 4 according to an embodiment of the present invention. Figure 3 This is a cross-sectional view of electrode plate 4 according to an embodiment of the present invention. Figure 4 for Figure 3 Enlarged view of part A, Figure 5 for Figure 3 The enlarged view of part B shows the electrode plate 4, which includes a conductive plate 42, a discharge plate 43, and a copper busbar 41. An insulating plate 45 is disposed between the conductive plate 42 and the discharge plate 43. The conductive plate 42 is connected to the copper busbar 41, which is connected to the anode of the power supply. The area of ​​the discharge plate 43 is smaller than that of the conductive plate 42, and the area of ​​the insulating plate 45 is equal to that of the discharge plate 43. A fluid channel 48 is provided on the electrode plate 4. The fluid channel 48 consists of multiple through holes of a predetermined diameter, preferably 28 Φ80mm through holes, in the assembly composed of the conductive plate 42, the discharge plate 43, and the insulating plate 45, to enhance the fluidity of the working fluid and optimize the reaction efficiency. The copper busbar 41 is preferably made of T2 copper, the conductive plate 42 is preferably made of TA2 pure titanium, and its dimensions are preferably 1520×1200mm; the discharge plate 43 is preferably made of TA2 pure titanium, and its dimensions are preferably 1020×1200mm, and a 3-5.3 micrometer platinum layer is plated on the working surface of the strip steel on side 6; a platinum plating thickness of 3-5.3 micrometers can balance conductivity and stability, and the plating on the working surface of the strip steel on side 6 is preferably 4.5 micrometers. This platinum interface is the core area where the electrochemical reaction occurs, directly undertaking the key work of current release and electrochemical conversion. The insulating plate 45 is preferably made of alkali-resistant fiberglass, and its dimensions are preferably 1020×1200mm.

[0044] The method for removing the oxide film from the surface of the tin-plated layer of steel strip of the present invention is set after the softening treatment process of the steel strip 6 and before the steel strip 6 enters the electroplating chromium working bath. It can effectively remove the oxide film while ensuring that the tin plating layer itself is not damaged. The method includes the following steps:

[0045] After the strip steel 6 is softened, a pretreatment working tank 2 is set up;

[0046] Electrode plates 4 and conductive rollers 5 are arranged in the pretreatment working tank 2 and filled with Na2CO3 working solution; strip steel 6 is located between two sets of symmetrically arranged electrode plates 4, and the conductive rollers 5 are in contact with the strip steel 6 to conduct cathode current;

[0047] The electrode plate 4 is connected to the positive terminal of the power supply, and the conductive roller 5 is connected to the negative terminal of the power supply. In the pretreatment working tank 2, the strip steel 6 is used as the cathode, the electrode plate 4 is used as the anode, and the Na2CO3 solution is used as the working fluid to form an electrolytic circuit. Through weak alkaline electrolytic treatment, the oxide film on the surface of the tin-plated layer of the strip steel undergoes an electrochemical reaction and is removed.

[0048] The electrode plate 4 uses pure titanium plate as the substrate. The discharge surface of the pure titanium plate facing the strip steel 6 and its conductive contact surface are both plated with a platinum layer. Current is conducted to the discharge surface of the electrode plate 4 through evenly distributed conductive bolts 44. The conductive bolts 44 are preferably made of titanium alloy, with their contact surfaces with other components plated with 3-micron platinum. The conductive gaskets 46 are preferably made of TA2 pure titanium, with their contact surfaces plated with 3-micron platinum. The locking nut 47 is made of titanium alloy, with its contact surfaces with other components plated with 3-micron platinum. All conductive interfaces are plated with platinum to construct a highly reliable current path. The conductive contact surfaces include the connection contact surface between the copper busbar 41 and the electrode plate 4, and the energized contact surface between the conductive bolts 44 and the gasket. Platinum is chosen primarily because of its excellent conductivity and superior chemical inertness: the former ensures efficient current transmission and reduces energy loss; the latter makes it corrosion-resistant and oxidation-free under complex operating conditions, thereby significantly improving the long-term operational stability and service life of the product. To effectively reduce contact resistance, all critical conductive interfaces are plated with a 4.5-micron-thick platinum layer. This platinum layer covers two main contact surfaces: the contact surface between the copper busbar 41 and the conductive plate 42; and the contact surface between the conductive screw and the copper busbar 41 and the conductive plate 42.

[0049] In this embodiment, after the oxide film on the surface of the tin-plated strip is removed, the strip 6 is directly entered into the spray tank for rinsing, and after rinsing, it enters the tin-chromium-iron working tank to complete the surface chromium plating process.

[0050] The reaction principle in this embodiment is as follows:

[0051] Cathodic reaction on the surface of strip 6:

[0052] SnO + H2O + 2e - → Sn + 2OH - ;

[0053] 2H2O +2e - → H2↑+2OH - ;

[0054] Anodic reaction on the surface of electrode plate 4:

[0055] 4OH - → 2H₂O + O₂↑ + 4e - ;

[0056] Overall reaction (corresponding to the cathode reaction, which occurs simultaneously during electrolysis):

[0057] 2SnO → 2Sn + O2↑ (corresponding to cathode reaction 1);

[0058] 2H₂O → 2H₂↑ + O₂↑ (corresponding to cathode reaction 2);

[0059] Electrode plate 4 is connected to the anode of the power supply, and strip 6 is connected to the cathode of the power supply via conductive roller 5, forming an electrolytic circuit in the Na2CO3 working solution. The oxide film on the surface of strip 6 is removed through an electrochemical reaction under the action of current.

[0060] During the remelting process, the tin plating layer not only develops a bright metallic luster under heat, but also reacts with some of the iron in the strip 6 substrate to form the intermetallic compound FeSn2 (tin-iron alloy layer), which significantly improves the corrosion resistance of the tin-plated sheet. After the remelting process, the strip 6 is immediately sent to the pretreatment working tank 2 of the subsequent tin-chromium-iron process section. At this stage, in addition to the formation of FeSn2, a thin oxide film that causes discoloration also forms on the tin-plated surface, requiring electrochemical cleaning. The device uses the strip 6 as the cathode and the electrode plate 4 as the anode, employing a weakly alkaline solution containing carbonates such as Na+ and K+ as the working fluid. Current is conducted to the discharge surface of the electrode plate 4 through uniformly distributed titanium alloy studs, ensuring uniform current density and stable and controllable process, thereby efficiently and uniformly removing the surface oxide film. After the oxide film is removed, the strip 6 directly enters the spray tank for rinsing. As a continuous production process, this process does not have intermediate inspection links; after rinsing, it enters the tin-chromium-iron working tank to complete the surface chromium plating process.

[0061] In this embodiment, the insulating plate 45 is preferably made of alkali-resistant fiberglass, which combines excellent electrical insulation, outstanding corrosion resistance, and remarkable mechanical strength. The conductive bolt 44 is preferably made of titanium alloy, with its contact surface with other components plated with 3 micrometers of platinum. In applications requiring integrated structural load-bearing and electrical conduction, titanium alloy studs are the optimal choice due to their superior comprehensive performance, achieving the best balance between extremely high mechanical strength, corrosion resistance, reliability, and good conductivity. The discharge plate 43 is preferably made of TA2 pure titanium. The conductive gasket 46 is preferably made of TA2 pure titanium, with its contact surface plated with 3 micrometers of platinum. The locking nut 47 is preferably made of titanium alloy, with its contact surface with other components plated with 3 micrometers of platinum. To ensure low resistance at all conductive contact surfaces, the following locations of key components are platinum-plated: the Φ50 contact area on the back of the electrode plate; the internal thread and bottom surface of the locking nut 47; and the entire surface of the stud (around the perimeter and top and bottom surfaces), thereby ensuring a complete and low-resistance conductive path is formed between the nut, stud, gasket, and electrode plate.

[0062] A platinum plating thickness ranging from 3 to 5.3 micrometers balances conductivity and bonding stability. Therefore, a plating thickness of 3 micrometers is preferred for the conductive contact surfaces of bolts, nuts, and washers to ensure both conductivity and a strong plating. Titanium alloy conductive fasteners integrate structural load-bearing and electrical conduction functions, offering the combined advantages of high strength, corrosion resistance, and lightweight design. A 4.5-micrometer plating thickness on the discharge surface of the electrode is optimal, fully leveraging its excellent conductivity and extremely high chemical stability to ensure long-term operation of the electrode under harsh conditions. The connection contact surface between the copper busbar 41 and the electrode is also plated with 4.5 micrometers of platinum to provide low and stable contact resistance, ensuring durable, efficient, and reliable power transmission. These configurations together create a complete system that is efficient, stable, and durable from internal electrochemical reactions to external electrical connections, achieving an optimal balance between overall performance and service life.

[0063] The conductive contact interface of this invention employs a platinum plating layer, constructing a highly reliable, low-impedance current transmission path. The titanium alloy studs, with their excellent conductivity and the significantly increased contact area resulting from the threaded structure, effectively reduce contact resistance. This structure allows minute currents to preferentially flow through this efficient path, avoiding the problems of disordered current paths and low efficiency in traditional connections. Simultaneously, the evenly distributed arrangement of the conductive bolts 44 ensures uniform current distribution from the rear end of the substrate to the front end of the plating surface, eliminating localized overheating or current dead zones, thereby improving current control accuracy and overall stability.

[0064] The electrode plate 4 of this invention uses titanium plate (TA2) as the base material. Compared with the Q235A grade steel (Q235-AZ) that is more commonly used in the past, titanium plate has superior corrosion resistance. However, the conductivity of titanium plate is not as good as that of Q235A steel. Therefore, this invention coats the discharge surface and conductive contact surface of electrode plate 4 with a platinum layer, which significantly enhances the conductivity of electrode plate 4 and effectively reduces power consumption.

[0065] Between the conductive substrate (i.e., titanium substrate) and the discharge functional surface (i.e., platinum plating), uniformly arranged titanium alloy bolts are used for current conduction. This not only achieves efficient current transmission to the discharge surface, but also improves the precise control capability of micro-current processing, thereby ensuring the uniformity of oxide film removal treatment on the surface of strip steel 6.

[0066] This invention uses strip steel 6 as the cathode and electrode plate 4 as the anode, forming a circuit in a specific working fluid. Na2CO3 solution is selected as the working fluid, and the oxide film on the tin-plated layer is removed through weakly alkaline electrolysis, effectively avoiding excessive corrosion of the tin layer. Pure titanium plate is used as the substrate, with platinum plating on both the discharge surface and conductive contact surface, providing excellent corrosion resistance and high conductivity, significantly reducing energy consumption. Furthermore, uniformly distributed titanium alloy bolts conduct current to the discharge plate 43, improving the control accuracy of the electrode plate under low-current processing conditions and ensuring the uniformity of the surface treatment of strip steel 6.

[0067] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the appended claims.

Claims

1. A method for removing the surface oxide film of a tin-plated steel strip, characterized in that, A strip steel continuous electro-tinning-chromium plating production line, comprising the following steps: After strip steel reflow treatment, a pretreatment work tank is arranged; An electrode plate is arranged in the pretreatment work tank, an electrically conductive roller is arranged above the pretreatment work tank, and the pretreatment work tank is filled with Na2CO3 working solution; the strip steel is located between two groups of symmetrically arranged electrode plates, the electrically conductive roller is in contact with the strip steel and conducts current; and The electrode plate is connected to the positive pole of a power supply, the electrically conductive roller is connected to the negative pole of the power supply, the strip steel is used as a cathode, the electrode plate is used as an anode, and Na2CO3 solution is used as working solution to form an electrolysis loop, so that the oxide film on the surface of the strip steel tinning layer is removed through weak alkaline electrolysis treatment.

2. The method of removing the surface oxide film of the tin-plated layer of the strip steel according to claim 1, characterized in that, The electrode plate uses a pure titanium plate as a base material, the discharge surface of the pure titanium plate facing the strip steel and the electrically conductive contact surface are plated with a platinum-gold layer, and current is conducted to the discharge surface of the electrode plate through evenly arranged electrically conductive bolts.

3. The method of removing the surface oxide film of the tin-plated layer of the strip steel according to claim 1, characterized in that, After the oxide film on the surface of the strip steel tinning layer is removed, the strip steel directly enters a spray tank for rinsing, and then enters a tin-chromium iron work tank to complete the surface chromium plating process.

4. The method of removing the surface oxide film of the tin-plated layer of the strip steel according to claim 1, characterized in that, The electrode plate comprises an electrically conductive plate, a discharge plate, and a copper bar, an insulating plate is arranged between the electrically conductive plate and the discharge plate, the electrically conductive plate is connected to the copper bar, and the copper bar is connected to the positive pole of a power supply.

5. The method of removing the surface oxide film of the tin-plated layer of the strip steel according to claim 4, characterized in that, The area of the discharge plate is smaller than the area of the electrically conductive plate, and the area of the insulating plate is equal to the area of the discharge plate.

6. The method of removing the surface oxide film of the tin-plated layer of the strip steel according to claim 4, characterized in that, A fluid channel is arranged on the electrode plate, the fluid channel is a plurality of through holes with a certain diameter arranged in an assembly composed of the electrically conductive plate, the discharge plate, and the insulating plate, the fluidity of the working solution is enhanced to optimize the reaction efficiency.

7. The method of removing the surface oxide film of the tin-plated layer of the strip steel according to claim 4, characterized by, The copper bar is made of T2 red copper, the electrically conductive plate is made of TA2 pure titanium, the discharge plate is made of TA2 pure titanium and plated with a 3-5.3 micron platinum-gold layer on the working surface facing the strip steel, and the insulating plate is made of alkali-resistant glass steel.

8. The method of removing the surface oxide film of the tin-plated layer of the steel strip according to claim 4, characterized by, The electrically conductive bolt is a titanium alloy bolt.

9. The method of removing the surface oxide film of the tin-plated layer of the steel strip according to claim 4, characterized by, The electrically conductive contact surface comprises a connecting contact surface between the copper bar and the electrode plate, and a power transmission contact surface between the electrically conductive bolt and the gasket.

10. An apparatus for removing the surface oxide film of a tin-plated strip, characterized in that A method for removing the oxide film on the surface of the strip steel tinning layer according to any one of claims 1-9.

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