How to properly carry out anti-corrosion treatment for high-altitude guardrails on facilities of coastal enterprises

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This post was last edited by Shutong on 2020-7-9 at 08:54. First, it is necessary to analyze the corrosion of railings in marine climates. Since the eastern coastal areas of China have a marine climate characterized by high air humidity and high chloride ion levels, chemical plants, under the severe conditions of marine atmospheric corrosion, experience rapid corrosion of their various components, especially steel railings. Over time, the anti-corrosion topcoat of the guardrail showed varying degrees of flaking and peeling; there were also a few bubbles and rust spots in some areas. If effective anti-corrosion measures are not taken in a timely manner for the steel guardrails, it will affect their crash resistance and service life, posing a potential threat to the safety of workers working at heights.

Features of the coating solution for marine climate railings: The primer layer uses 881-X epoxy zinc-rich primer, which provides excellent cathodic protection. Moreover, epoxy coatings require little attention to surface preparation – a surface finish of St 3 level is sufficient – thereby ensuring long-lasting corrosion resistance between the coating system and the steel structure of the railing. The intermediate coat uses 881-Z01 epoxy limonite intermediate paint, which contains a large amount of mica-iron oxide ash that arranges in layered form within the paint film. This arrangement effectively prolongs the path that corrosion agents can take, enhancing the coating’s resistance to media penetration. It possesses good water resistance, acid and alkali resistance, as well as wear resistance, thereby extending the service life of the anti-corrosion coating. The topcoat layer uses 881-Y11, a tetrafluorinated fluorocarbon topcoat that boasts excellent ultra-weather resistance, resistance to humid heat, salt spray, and acid rain. Meanwhile, its paint film is tough, offering good impact resistance and wear resistance.

Polyaniline nano-primer + fluorocarbon topcoat is fine.

Regarding the anti-corrosion treatment of high-altitude guardrails installed on coastal enterprises’ facilities, especially the repair work on steel structures in second-phase construction, it is not possible at the site to achieve a metal sandblasting level of Sa2.5 and/or to reach the St grade. There are large amounts of rust products on the metal surface, which means that ordinary zinc-rich coatings or epoxy primers are not effective. This is also a challenge in secondary anti-corrosion restoration. However, there is currently a high-weatherability metal paint with low surface treatment that can solve these problems quite well. For metal surface treatment, loose rust, flaking, and poorly adhered coatings can be manually removed before painting. It can be used for over 8 years with one coat of paint.