Cathodic protection of cargo/ballast tanks of crude oil tankers

✍ Scribed by C. de Waard; W. Posch

• Publisher: John Wiley and Sons
• Year: 1972
• Tongue: German
• Weight: 400 KB
• Volume: 23
• Category: Article
• ISSN: 0947-5117
• DOI: 10.1002/maco.19720231108

✦ Synopsis

Abstract

Unless a special protection is provided pitting corrosion may occur on top and at the bottom of ballast tanks. Usually a partial coating (horizontal areas) is used in connection with cathodic protection by sacrificial anodes. More than two years' observation of coated and uncoated, cathodically protected containers has shown, that anode efficiency is generally better than 90%, and in many cases as high as 100%. The current densities measured depend from the point of measurement and are higher at the bottom, in particular when the latter is coated. On the basis of the measurement results it is possible to assess the protective current requirements for horizontal anc vertical surfaces.