Magnesium anodes

Description

Among sacrificial anode materials, magnesium has the highest dynamic polarization potential. It is most often used for onshore installations, in resistive electrolytes where the use of zinc or aluminium would not be economical: onshore pipelines, buried storage tanks, water reservoirs, caissons and hulls in fresh or brackish water, or the temporary protection of pipelines before an impressed-current system is commissioned.

The anodes are available in two alloy types, with output potentials of around 1.55 V (low potential) and 1.75 V (high potential) relative to a copper/copper sulphate reference electrode, for a capacity of 1,230 Ah/kg. Two shapes are available: round (vertically cast) from 3.6 to 27.3 kg, or D-shape (horizontally cast) from 2.3 to 7.7 kg.

For buried pipelines and tanks, the anodes are generally supplied pre-conditioned in a cotton bag surrounded by backfill (75% gypsum, 20% bentonite, 5% sodium sulphate), which evens out the current output and dissolution rate while lowering the electrolyte resistance. The connecting cable is the customer's choice; we recommend 3 m of red KATHODICA™ cable, 6 mm² multi-strand copper, XLPE insulation and PVC sheath, rated 600/1000 V to IEC 502/83 and BS 5467.

Caractéristiques techniques

Documentation