Korozyona Uğramış Siloların Bakımı: Bir Vaka Çalışması

Abstract

Yakıt, gıda ve kimyasalların depolanması için kullanılan silolar, inşaat sektöründe yaygın olarak kullanılan çimento, agrega ve katkı maddeleri gibi çeşitli kimyasalları güvenli bir şekilde depolamak ve dağıtmak için tasarlanmış özel yapılardır. Cam elyaf takviyeli beton (GFRC) panel üretimi için gerekli malzemelerin çoğu silolarda depolanır. Gerekli malzemeler, otomatik dozaj sistemi ile donatılmış pompalar yardımıyla silolardan alınır. Havadaki nem ve oksijene maruz kalan siloların korozyona uğrayıp pas oluşturması yüksek ihtimaldir. Açık havada, özellikle aşırı nem ve yağış alan yerlerde silolar zamanla daha hızlı korozyona uğrar. Dolayısıyla korozyon nedeniyle delinen silolar üretimin durmasına ve ciddi mali kayıplara yol açabilir. Boyama, metal yüzey ile çevre arasında bir bariyer oluşturarak korozif maddelerle doğrudan teması önlediği ve çelik yapının ömrünü uzattığı için çeliği korozyondan korumanın başlıca yöntemlerinden biridir. Bu çalışmada, Fibrobeton GFRC şirketi tarafından 20 yıldır kullanılan ve ağır korozyona uğramış iki silonun bakım çalışmaları ASTM D3276, ISO 8501 ve ISO 12944:2018 standartlarına göre adım adım gerçekleştirilmiştir. Eski boyanın silo yüzeyinden uzaklaştırılması için sulu kumlama kullanılmış, ardından korozyon inhibitörleri içeren patentli bir asit çözeltisi (TPE Patent Başvuru No: 2017/11354) ile oksit tabakası temizlenmiş, ardından iki kat yüzey toleranslı (Zn₃(PO₄)₂ bazlı) epoksi boya ve ardından UV dayanımı yüksek akrilik boya uygulanmıştır. Bu çalışmada bakım işlemi sırasında metal yüzeyin boya öncesi standartlara uygun olarak hazırlanmamasından kaynaklanan sorunlara da dikkat çekildi.

Keywords

• Korozyon
• silo
• boya
• bakım
• atmosferik korozyon

Maintenance of corroded silos: A case study

Abstract

Silos used for storing fuels, foods, and chemicals are specialized structures designed to safely contain and dispense various types of chemicals commonly used in the construction industry, such as cement, aggregates, and additives. Most of the materials required for glass fiber reinforced concrete (GFRC) panel production are stored in silos. The required materials are taken from the silos with the help of pumps equipped with an automatic dosage system. Steel is prone to corrosion when exposed to moisture and oxygen in the air, resulting in the formation of rust. In the open air, especially in places with excessive humidity and rainfall, silos corrode faster over time. Therefore, punctured silos due to corrosion can lead to production stoppages and severe financial losses. Painting is one of the primary methods for protecting steel from corrosion as it creates a barrier between the metal surface and the environment, preventing direct contact with corrosive agents and extending the life of the steel structure. In this study, the maintenance work of two heavily corroded silos, which had been in use for 20 years by Fibrobeton GFRC company, was carried out step by step according to ASTM D3276, ISO 8501 and ISO 12944:2018 standards. Wet sandblasting was used to remove the paint from the surface, followed by cleaning of the oxide layer with a patented acid solution (TPE Patent Application No: 2017/11354) containing corrosion inhibitors, followed by the application of two coats of surface tolerant (Zn₃(PO₄)₂ based) epoxy paint and then acrylic paint with high UV resistance. During this maintenance process, attention was also drawn to the problems caused by not preparing the metal surface in accordance with the standards before painting.

Keywords

• Corrosion
• silo
• paint
• maintenance
• atmospheric corrosion

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