[en] It is realized a study of the corrosion process and the products formed over the carbon steel in different points of the machine-room of the Electronuclear plant of Juragua (Cuba) particularly in the pipelines considering the specific characteristics of corrosion under roof which has been less studied. The determination of corrosiveness grade was carried out by gravimetric methods (lost and gain weight) in the different coats of the machine-room not existing a correlation between them in according to results with those ones obtained by Infrared Spectroscopy, in which there is not a correlation between the band intensities (lepidocrocite/ goethite) and the corrosion; however both explain different parts of corrosive process. Also it is realized the corrosion products analysis by chemical methods and by Atomic Absorption Spectrometry, obtaining the concentration of the major anions and cations of importance for the corrosion, not existing a meaning correlation between them and the corrosion velocity by what it was determined the absorption isotherms, obtaining as result a microporous structure in the formed oxides which was capable to retain and to absorb water and pollutants which could be this the main cause of corrosion. By analyzing the high concentration of iron and the low concentration of the remainder anions and cations it is possible to make the traditional chemical washes which are less expensive and greater effectiveness. All the obtained results are very important to assure the conditions of the pipelines systems installed at the presence of Government and Foreign organizations which are interested for the protection and conservation measures in the pipelines system. (Author)