Emerald Group Publishing Limited
Copyright © 2000, MCB UP Limited
MMO tubular and magnetite anodes
Keywords BAC Corrosion Control, Corrosion prevention
By paying close attention to materials sourcing and production techniques, BAC Corrosion Control reports that it has developed a new range of impressed current mixed metal oxide tubular anodes whose cost closely approaches those of equivalent silicon-iron and cheaper magnetite multiple anode strings. The anodes are said to be specifically designed to protect buried metallic structures from corrosion and due to their light weight and ease of installation, they eliminate the handling and installation problems associated with the heavy and brittle alternatives.
The tubular device comprises a titanium tube with a mixed metal oxide coating that activates the titanium electrically enabling it to function as an anode. With the cable connection in the middle of the tube, at a crimped section, even current distribution along the anode's length is claimed to be assured. Full internal moisture protection is provided by a complete filling of epoxy resin, end caps and cable seals. The BAC range comprises three pipe diameters and two pipe lengths with a variety of cable types to suit particular applications.
BAC explains that strung together the anodes can be used in vertical or horizontal groundbeds in fresh or seawater, soil or mud, from shallow trenches through to deep wells in very dry areas. The company also informs us that due to their light weight, they can be installed without resort to mechanical lifting equipment. For deep well applications the upper end of each anode in a string is fitted with centralising spigots.
With a very low consumption rate - milligrams per ampere/year - tube dimensions are said to stay almost constant during the life of these consistently low resistance anodes. Depending on application this is thought to be up to 20 years. Chemical stability of the anodes in soil, mud, fresh or seawater is reported to be very high, even in very low pH value environments and the coating is reportedly not affected by chlorine.
Details available from: BAC Corrosion Control, Tel: +44 (0) 1952 290321; Fax: +44 (0) 1952 290325; E-mail: email@example.com