Corrosion-resistant hoop and preparation method thereof

Abstract

The invention relates to the technical field of hoops, and provides a corrosion-resistant hoop and a preparation method thereof. The preparation method of the corrosion-resistant hoop comprises the following steps that flat steel is sequentially subjected to alkali washing, water washing, acid pickling, water washing, drying, plating assisting, drying, zinc plating, cooling, passivating and assembling, a plating assisting agent adopted for plating assisting comprises zinc chloride, ammonium chloride, a surfactant, a synergist and water, and the synergist comprises beta-(acryloyloxy) propionic acid. According to the technical scheme, the problem that the corrosion resistance of the hoop is insufficient due to the fact that the quality of a zinc coating formed on the surface of the hoop through a hot galvanizing process in the related technology is poor is solved.

Description

Technical Field

[0001] This invention relates to the field of clamp technology, specifically to a corrosion-resistant clamp and its preparation method. Background Technology

[0002] A clamp is a ring-shaped or semi-ring-shaped metal fastener mainly used for connecting utility poles to fittings, fixing crossarms, cables, and pipes, and providing support, limiting, and stabilization. It is widely used in engineering applications such as power transmission lines, power towers, communication lines, municipal water supply and drainage, building pipelines, and bridge foundations, and can withstand long-term loads and adapt to complex environments.

[0003] Since steel clamps are often used in environments with corrosive media such as humidity, acids, alkalis, or salt spray, their corrosion resistance is particularly critical. The most common process for improving the corrosion resistance of clamps is hot-dip galvanizing. Hot-dip galvanizing, also known as hot-dip zinc plating, is a process in which steel components are immersed in molten zinc to obtain a protective metallic layer for corrosion protection. Hot-dip galvanizing can significantly improve the corrosion resistance of clamps. However, traditional hot-dip galvanizing processes often result in a poor-quality zinc layer on the clamp surface, leading to insufficient corrosion resistance. Summary of the Invention

[0004] This invention proposes a corrosion-resistant clamp and its preparation method, which solves the problem that the hot-dip galvanizing process in related technologies produces a poor-quality zinc coating on the clamp surface, resulting in insufficient corrosion resistance of the clamp.

[0005] The technical solution of the present invention is as follows: A method for preparing a corrosion-resistant clamp includes the following steps: Alkali washing, water washing, acid washing, water washing, drying, fluxing, drying, galvanizing, cooling, passivation, and assembly of flat steel to obtain a corrosion-resistant clamp. The fluxing agent used in the fluxing process includes the following components: zinc chloride, ammonium chloride, surfactant, synergist, and water. The synergist includes β-(acryloyloxy)propionic acid.

[0006] As a further technical solution, the synergist also includes 4-acetoxybenzoic acid, wherein the mass of β-(acryloyloxy)propionic acid is ≥12 times the mass of 4-acetoxybenzoic acid.

[0007] The inventors discovered through experiments that when the mass of β-(acryloyloxy)propionic acid is ≥12 times the mass of 4-acetoxybenzoic acid, the combined use of β-(acryloyloxy)propionic acid and 4-acetoxybenzoic acid as synergistic agents exhibits a synergistic effect, providing a dense flux layer for hot-dip galvanizing, improving the quality of the galvanized layer, and thus significantly enhancing the corrosion resistance of the clamp. When the mass ratio of β-(acryloyloxy)propionic acid to 4-acetoxybenzoic acid is 12:1, the synergistic effect is even more significant, further improving the corrosion resistance of the clamp.

[0008] As a further technical solution, the mass-volume ratio of zinc chloride, ammonium chloride, surfactant, synergist, and water is 120g:180g:1~5g:10~15g:1L.

[0009] Ammonium chloride is used as the main component of the fluxing agent. The flat steel is fluxed before hot-dip galvanizing. After the fluxed flat steel is immersed in the zinc bath, the ammonium chloride decomposes into NH3 and HCl. HCl dissolves iron oxide, producing FeCl2 and FeCl3. FeCl2 and FeCl3 are reduced by zinc, improving the wettability between the zinc bath and the flat steel. By combining ammonium chloride with zinc chloride, surfactants, and synergists as a fluxing agent, a high-quality zinc coating is ensured, providing a foundation for the excellent corrosion resistance of the clamps.

[0010] As a further technical solution, the surfactant includes one or more of sodium dodecylbenzenesulfonate, sodium dodecyl sulfonate, and sodium fatty alcohol ether sulfate.

[0011] The addition of surfactants can improve the quality of the salt film on the surface of the plated part, providing a foundation for a more complete and uniform salt film coverage, and enhancing the isolation effect of the flux salt film on the plated part; at the same time, it can also enable the flux to have a good wetting effect on the plated part. The surfactant can be selected from any one or more of fatty alcohol polyoxyethylene ether, dodecylphenol polyoxyethylene ether, octylphenol polyoxyethylene ether, sodium dodecylbenzene sulfonate, sodium dodecyl sulfonate, and sodium fatty alcohol ether sulfate, preferably one or more of sodium dodecylbenzene sulfonate, sodium dodecyl sulfonate, and sodium fatty alcohol ether sulfate.

[0012] As a further technical solution, before the flat steel is alkaline washed, it is cut, punched, and bent into shape in sequence.

[0013] As a further technical solution, the alkaline washing is performed using an 8wt%~15wt% sodium hydroxide aqueous solution at room temperature; the acid washing is performed sequentially using sulfuric acid and hydrochloric acid, wherein the concentration of sulfuric acid is 10wt%~20wt% and the concentration of hydrochloric acid is 20wt%~30wt%.

[0014] Alkaline washing is used to remove organic contaminants, such as dirt and grease, introduced during the initial processing, transportation, and storage of flat steel. Pickling is used to remove oxide scale from the flat steel. Sulfuric acid pickling is performed at 50-60℃, while hydrochloric acid pickling is performed at 30-40℃. Both alkaline and pickling treatments require neutralization with water.

[0015] As a further technical solution, the temperature of the fluxing process is 50~60℃ and the time is 1.5~2.5min.

[0016] As a further technical solution, the zinc plating is performed by immersion in a molten zinc bath for 0.5 to 1 minute.

[0017] The workpiece is immersed in a molten zinc bath at 450°C for 0.5 to 1 minute, and then removed from the zinc bath. Excess liquid zinc metal flows into the zinc bath, and the liquid zinc metal adhering to the surface solidifies to form a zinc plating layer.

[0018] The present invention also proposes a corrosion-resistant clamp, which is prepared by the aforementioned preparation method.

[0019] The working principle and beneficial effects of this invention are as follows: This invention provides a method for preparing corrosion-resistant clamps. By introducing a new flux into a conventional process, the flux uses β-(acryloyloxy)propionic acid as a synergist. This method utilizes the ester group in β-acryloyloxypropionic acid in its molecular structure to react with the NH4+ in ammonium chloride. 4+ Hydrogen bonds are formed, and carboxyl groups are adsorbed on the surface of the workpiece, so that the salt film completely covers the surface of the workpiece, thereby improving the quality of the zinc coating and achieving the effect of improving the corrosion resistance of the clamp. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] Example 1 After cutting, punching, and hot bending of Q235 flat steel, it is alkaline washed at room temperature with a 10wt% sodium hydroxide aqueous solution, neutralized by water washing, first pickled with a 10wt% sulfuric acid solution at 60℃, then pickled with a 20wt% hydrochloric acid solution at 40℃, neutralized by water washing, and then dried. The dried flat steel was coated with a flux at 50°C for 2.5 minutes. The flux consisted of zinc chloride, ammonium chloride, sodium dodecyl sulfonate, synergist, and water in a mass-to-volume ratio of 120g:180g:1g:15g:1L. The synergist was β-(acryloyloxy)propionic acid. After drying, the steel was immersed in a molten zinc bath at 450°C for 0.5 minutes. After immersion, the steel was removed from the zinc bath, cooled, passivated, and assembled to obtain a corrosion-resistant clamp.

[0022] Example 2 After cutting, punching, and hot bending of Q235 flat steel, it is alkaline washed at room temperature with a 15wt% sodium hydroxide aqueous solution, neutralized by water washing, first pickled with 20wt% sulfuric acid at 50℃, then pickled with 30wt% hydrochloric acid at 30℃, neutralized by water washing, and dried. The dried flat steel was flux-plated at 60℃ for 1.5 minutes. The flux used consisted of zinc chloride, ammonium chloride, sodium dodecylbenzenesulfonate, synergist, and water in a mass-volume ratio of 120g:180g:5g:10g:1L. The synergist was β-(acryloyloxy)propionic acid. After drying, the steel was immersed in a molten zinc bath at 450℃ for 1 minute. After immersion, the steel was removed from the zinc bath, cooled, passivated, and assembled to obtain a corrosion-resistant clamp.

[0023] Example 3 The only difference from Example 2 is that the synergist is β-(acryloyloxy)propionic acid and 4-acetoxybenzoic acid in a mass ratio of 9:1.

[0024] Example 4 The only difference from Example 2 is that the synergist is β-(acryloyloxy)propionic acid and 4-acetoxybenzoic acid in a mass ratio of 12:1.

[0025] Example 5 The only difference from Example 2 is that the synergist is β-(acryloyloxy)propionic acid and 4-acetoxybenzoic acid in a mass ratio of 14:1.

[0026] Comparative Example 1 The only difference from Example 2 is that no synergist is added.

[0027] Performance testing: (1) Quality of galvanized layer: Before passivation, the galvanized parts were subjected to a hot-dip galvanized layer uniformity test according to the method in GB / T 2694-2018, and the number of corrosion resistance tests were recorded.

[0028] (2) Corrosion resistance: The artificial atmosphere corrosion test - acetic acid salt spray test was carried out according to the method in GB / T 10125-2021, and the percentage of the corrosion area to the total area after 480h was recorded.

[0029] The results are recorded in Table 1.

[0030] Table 1. Test results of zinc coating quality and corrosion resistance.

[0031] As shown in Table 1, the corrosion-resistant clamp provided by this invention has a high-quality zinc plating layer and good corrosion resistance. Example 2 has a higher number of immersion corrosion cycles than Comparative Example 1, and the percentage of corrosion area to total area after 480 hours is lower than that of Comparative Example 1, indicating that the addition of β-(acryloyloxy)propionic acid improves the quality of the zinc plating layer and achieves the effect of improving the clamp's corrosion resistance.

[0032] In addition, the zinc layer adhesion test was performed on the plated parts before passivation according to the method in GB / T 2694-2018. After the hammer test in Examples 1 to 5, the zinc layer did not bulge or peel off, and the zinc layer had good appearance quality, smooth, without drips, roughness and zinc spikes, no peeling and no missing plating.

[0033] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a corrosion-resistant clamp, characterized in that, Includes the following steps: Flat steel is subjected to alkali washing, water washing, acid washing, water washing, drying, fluxing, drying, galvanizing, cooling, passivation, and assembly in sequence to obtain corrosion-resistant clamps. The fluxing agent used in the fluxing process includes the following components: zinc chloride, ammonium chloride, surfactant, synergist, and water. The synergist includes β-(acryloyloxy)propionic acid.

2. The method of claim 1, wherein the corrosion-resistant banding is prepared by the steps of: The synergist also includes 4-acetoxybenzoic acid, wherein the mass of β-(acryloyloxy)propionic acid is ≥12 times the mass of 4-acetoxybenzoic acid.

3. The method of claim 2, wherein the corrosion-resistant banding is prepared by the steps of: The mass ratio of β-(acryloyloxy)propionic acid to 4-acetoxybenzoic acid is 12:

1.

4. The method of claim 1, wherein the corrosion resistant banding is made of a material selected from the group consisting of: stainless steel, titanium, and a combination thereof. The mass-volume ratio of zinc chloride, ammonium chloride, surfactant, synergist, and water is 120g:180g:1~5g:10~15g:1L.

5. The method for preparing a corrosion-resistant clamp according to claim 1, characterized in that, The surfactant includes one or more of sodium dodecylbenzenesulfonate, sodium dodecyl sulfonate, and sodium fatty alcohol ether sulfate.

6. The method for preparing a corrosion-resistant clamp according to claim 1, characterized in that, Before alkaline washing, the flat steel is cut, punched, and bent into shape in sequence.

7. The method for preparing a corrosion-resistant clamp according to claim 1, characterized in that, The alkaline washing is performed using an 8wt%~15wt% sodium hydroxide aqueous solution at room temperature. The acid washing is performed sequentially using sulfuric acid and hydrochloric acid, wherein the concentration of sulfuric acid is 10wt%~20wt% and the concentration of hydrochloric acid is 20wt%~30wt%.

8. The method for preparing a corrosion-resistant clamp according to claim 1, characterized in that, The temperature of the flux plating is 50~60℃, and the time is 1.5~2.5min.

9. The method for preparing a corrosion-resistant clamp according to claim 1, characterized in that, The zinc plating is performed by immersion in a molten zinc bath for 0.5 to 1 minute.

10. A corrosion-resistant clamp, characterized in that, It is prepared by the preparation method according to any one of claims 1 to 9.

Images