JP2009256761A - Corrosion prevention method by plating-resin film for iron based material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a practical corrosion protection method by plating and a resin by means of a plating layer and resin film having uniform thickness and excellent corrosion resistance, and to provide a grating applying the method. <P>SOLUTION: In the corrosion prevention method, an iron-based material is subjected to plating pretreatment including a step where it is treated with a ferric chloride solution, is thereafter subjected to hot dip galvanizing, is then subjected to hot dip zinc-aluminum alloy coating, and is further subjected to chemical conversion treatment, subsequently, the surface thereof is coated with a liquid, and resin powder is stuck thereto by fluidization dipping to form a resin film. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention belongs to hot dip galvanizing and painting. The present invention also relates to a structure subjected to plating and painting.

  For rusting iron-based materials (steel, cast steel, cast iron, etc.), hot dip galvanizing is used to provide corrosion resistance. However, near the coast, further countermeasures against salt damage are required, and melting with better corrosion resistance is required. Zinc plating (alloy plating including aluminum) is becoming necessary. Further, in some cases, further coating is required on these galvanized plates for corrosion resistance and appearance.

  The hot dip galvanizing or coating is expensive, and it is desirable that the thickness is uniform and the corrosion resistance is excellent. In particular, a complicated structure has a problem that plating and paint easily accumulate in corners and narrow spaces, and not only the function and appearance deteriorate, but also the cost increases.

  For example, there is grating. Some of the recent gratings are so fine that the heels of the high heels do not fall in between, the corners can easily accumulate, and if the plating or coating is thick, the surface of the lattice becomes semi-cylindrical, so that There was a problem that the heel was slippery.

  In the manufacturing of gratings, cleaning of the surface of the weld zone, welding stress and surface hardening stress, etc. are factors that hinder uniform plating. Although it was used, heat was trapped between the grids, and the coating on this part became thick, and peeling and cracking were likely to occur due to the load.

  To obtain a practical anticorrosion method having uniform thickness and excellent corrosion resistance by hot dip galvanizing and resin, and providing a grating to which the method is applied.

  The anticorrosion method is a method in which a ferrous material is subjected to a pretreatment for plating including a step of treating with a ferric chloride solution, followed by hot dip galvanizing, followed by hot dip zinc-aluminum alloy plating. In this method, a liquid is applied and resin powder is adhered by fluid immersion to form a resin film.

  Resistant to salt damage. The thickness of plating and resin coating is uniform, less material is required, and the appearance can be refreshed without bottling. Grating is not slippery because the lattice does not have a kamaboko shape.

  The steps of the anticorrosion method of the present invention are basically composed of three steps of hot dip galvanizing, hot dip zinc-aluminum alloy plating, and resin coating by fluid immersion, and before and after these treatment steps.

  The first hot dip galvanizing is performed by pre-treatment soaking in a ferric chloride solution. By this treatment, burrs, corners, weld surfaces, high stress portions, and the like are etched, and a substrate with a thin and uniform plating can be obtained. After that, pickling, flux treatment, and hot dip galvanizing. Prior to these treatments, a degreasing or shot blast treatment is performed if necessary.

  After the hot dip galvanizing, the hot dip galvanized aluminum alloy plating is performed without any treatment. If necessary after plating, the plating pool is removed with a centrifuge or water-cooled.

  After plating, chemical conversion treatment is performed, and a resin film is formed by fluid immersion. In the case of a material such as grating, which is likely to accumulate heat, a resin film is formed by a post-heating method. That is, a liquid (primer) that acts as a paste is applied to the surface, and this is immersed in a fluidized tank so that the powder adheres, and this is heated to melt the powder resin to form a resin film. In this method, if the primer has a uniform thickness, the thickness of the powder adhering to the primer is also uniform, and as a result, a film having a uniform thickness can be obtained.

  As the primer, various liquid substances can be considered, but an aqueous triethanolamine solution that is not an organic solvent is easy to handle and suitable.

  The above-mentioned method was applied to grating, and it was confirmed that it was a practical method that could stably and quickly obtain good products. For example, if the treatment with ferric chloride solution is omitted, the surface and corners cannot be plated smoothly, the hot dip galvanization is removed, hot dip zinc-aluminum alloy plating cannot be performed (flux does not work), and the grating with a narrow lattice spacing is Unless it is a post-heating method, a resin film having a uniform thickness cannot be obtained.

  Since a practical method has been established, it can be used for those requiring the same kind of surface treatment.

Claims (6)

  After pre-plating treatment including the step of treating ferrous chloride with ferrous chloride solution, hot dip galvanization, then hot dip zinc-aluminum alloy plating, and after chemical conversion treatment, a resin coating is formed by fluid immersion. A method for preventing corrosion of an iron-based material, characterized by being formed.   The anticorrosion method according to claim 1, wherein the ferrous material is treated with a ferric chloride solution, and then pickled and fluxed.   The anticorrosion method according to claim 1 or 2, wherein the iron-based material is first shot blasted.   The anticorrosion method according to any one of claims 1 to 3, wherein after the chemical conversion treatment, a liquid is applied to the surface, a resin powder is adhered by fluid immersion, and a resin film is formed by baking (melt curing).   5. The anticorrosion method according to claim 1, wherein the liquid applied to the surface is triethanolamine.   The iron-type grating which gave the anticorrosion by Claims 1-5.