Anodes Suitable for Water

Although rod anodes screwed into the side walls of containers are preferred, plate anodes and basket anodes are mostly necessary on the base. They are particularly suitable for large containers without being built in. Plate anodes are supplied with a fiat plastic holder to which the cable conductor is attached and 

In such cases basket anodes are frequently used. These have a relatively large surface and work at a low driving voltage due to their special construction. A cylinder of platinized titanium-expanded metal serves as the basket to which a titanium rod is welded. This serves as the current lead and carrier, and ends in a plastic foot that contains the cable lead and at the same time serves as the mounting plate. The expanded metal anode exhibits a very uniform anode current density distribution, even at large dimensions, in contrast to the plate anode. The reason is the many comers and edges of the metal that make the point effect only evident at the outer edges of the anode. 

In internal protection, attention must be paid to the fact that mixed gases that contain hydrogen and oxygen are evolved by the protection current. Noble metals and noble metal coatings can catalyze an explosion. The safety measures required in this case are presented in DIN 50927 [32] (see also Section 20.1.5). 

With impressed current stations on privately owned sites, it is advisable to conclude contracts with the property owner in order to guarantee access to the installation at all times, to prevent damage to the cables and to exclude construction or modifications in the area of the anode beds. 

In choosing a site for protection installations for steel-water structures, decisive factors are the location in the harbor area and the need to keep the lengths of cable to the protected object and anode as short as possible where very high protection currents are involved. 

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