What Does Silicon Iron Anode Mean?
Silicon iron anodes are tubular- or rod-shaped anodes that are used for the cathodic protection of pipelines, tanks and marine structures. Silicon iron anodes contain 14.5% silicon iron alloy with 4.5% added chrome to provide the utmost resistance to a wide range of corrosive environments.
Cathodic protection can be done with the help of one of two methods, either by using galvanic anodes (also known as sacrificial anodes) or impressed current systems. Silicon iron anodes are predominantly suited for impressed current cathodic protection (ICCP) systems.
Corrosionpedia Explains Silicon Iron Anode
Silicon iron anodes are used to control the high electrolyte resistivity when impressed current cathodic protection (ICCP) systems are used to protect large structures from corrosion. A reason for avoiding galvanic or sacrificial anodes in such cases is that the galvanic anodes cannot economically deliver enough current to provide cathodic protection to a large structure.
In impressed current cathodic protection systems, anodes are connected to a DC power source, often a transformer-rectifier connected to AC power. Anodes used in the ICCP systems are usually manufactured either as solid tubes or rods, or continuous ribbons of various materials. The most common anodes in these systems are silicon iron anodes, graphite anodes, mixed metal oxide anodes and platinum-niobium coated wires.
Companies manufacturing silicon iron anodes also prefer to add little chromium, making them better suited to situations where chlorine or other aggressive agents may be generated by electrolysis. The rate of consumption of silicon iron anodes will vary based on the current density, environment and method of installation.