Corrosión de tuberías en instalaciones de edificación

Abstract

This paper deals with the behaviour during about one year, of cast-iron and galvanized cast-iron tubes used for water pipes in building instalations, either as such or previously wrapped up in newspaper —according to some local practices—, from the viewpoint of their corrosion in contact with cement mortars and concretes in which they are normally embedded. Provisional practical results of the study up to date, as well as their interpretation and evaluation and conclusions drawn from them emphasize how inadequate and damaging such practices may be and lead to reject their application. As far as the influence of PA-350 cements containing blast-furnace slags, and S-11-350 cements (blas-furnace slag cements) are concerned, which have been used in the work and are specified in Spanish Cement Standards RC-75, the results do not show any difference in behaviour between both cements, in the sense that neither the one nor the other cause corrosion of not wrapped cast-iron tubes, either galvanized or not, in the experimental working conditions, when observed after one year of embedment. The results also show the importance of using adequate materials and accomplishing regulations of good practice in building, to avoid the bad behaviour of either of the mentioned, tubes in water pipes, as far as their durability against corrosion is concerned.