Anodes high-silicon-chromium iron

Anode Selection High silicon, chromium bearing cast iron and graphite have similar characteristics. Dissipation rate varies with the environment, but... 

Design of cathodic protection for marine structures in both fresh and salt water require special techniques. Galvanic systems usually employ zinc or aluminum alloy anodes. Impressed current systems frequently use high silicon, chromium bearing iron, platinized niobium, or mixed-metal oxide/titanium anodes. The structure being protected affects the design. Stationary facihties such as bulkheads and support piles require different techniques from ship hulls [55]. 

In this case of a cathodic protection system, the weight and number of anodes to be used is calculated from the cycle life of the system. Prolonged life of the anode is essential to decrease maintenance cost of the impressed current cathodic protection system. Dissipation rate of the anode is a measure of the life of the anode. For high silicon, chromium bearing cast iron, the dissipation rate is 0.5 kg/A year. The weight of the anode is given by... 

High-silicon cast iron anodes must be of the chromium-containing alloy due to chlorine evolution and preferably be of tubular construction. Extreme care must be exercised in protecting cable connections and employing cable jacketing that... 

Silicon iron anodes are composed of iron as the base metal with about 15% silicon and 1% carbon, additionally alloyed with chromium (5%), manganese (1%) and molybdenum (2%). The maximum current output is 50A/m and the rate of consumption is between 90 and 250 g/A/year. Anodes containing Mo are used in high-temperature media. 

For more than a century, a number of different aluminum alloys have been commonly used in the aircraft industry These substrates mainly contain several alloying elements, such as copper, chromium, iron, nickel, cobalt, magnesium, manganese, silicon, titanium and zinc. It is known that these metals and alloys can be dissolved as oxides or other compounds in an aqueous medium due to the chemical or electrochemical reactions between their metal surfaces and the environment (solution). The rate of the dissolution from anode to cathode phases at the metal surfaces can be influenced by the electrical conductivity of electrolytic solutions. Thus, anodic and cathodic electron transfer reactions readily exist with bulk electrolytes in water and, hence, produce corrosive products and ions. It is known that pure water has poor electrical conductivity, which in turn lowers the corrosion rate of materials however, natural environmental solutions (e g. sea water, acid rains, emissions or pollutants, chemical products and industrial waste) are highly corrosive and the environment s temperature, humidity, UV light and pressure continuously vary depending on time and the type of process involved. ... 

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