Protective properties of a multi-layer external coating applied to underground pipes of ductile iron
DOI:
https://doi.org/10.36119/15.2020.8.5Keywords:
water supply pipes, oxide scale, thermal sprayed coating, sealing paintAbstract
In this work the analysis of corrosion for ductile iron pipes with diameters of 350 and 500 mm was performed. Two phenomena regarding the pipes coating deterioration have been recognized: corrosion and abrasion. The corrosion tests performed on different coatings in a neutral salt spray for up to 1000 hours indicate that this method is applicable for a rough external surface of centrifugally casted ductile iron pipes. The abrasion tests have been performed manually, using a grinding paper 1000#, due to an irregular profile of the external pipe surface transferred from the casting mold. It helped to obtain “spotted” sections, which were further microscopically analyzed (layer-by-layer). The last procedure, however not standardized, could be in some regards more convenient comparing to traditional cross-sections.
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References
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