| |
|
ANODES FOR CATHODIC PROTECTION
|
Ti Anode Fabricators Pvt. Ltd, Chennai, India has proven technology for making Mixed Metal Oxide (MMO) anodes for a full range of cathodic protection application, by using Impressed Current Cathodic Protection (ICCP) process.
The principle of cathodic protection is connecting an external anode to the metal to be protected and the passing of an electrical DC current so that all areas of the metal surface become cathodic and therefore do not corrode. The external anode is to be an impressed current cathodic protection anode, where the current is impressed from an external DC power source. DC current is sent through an insulated wire to the Dimensionally Stable Anodes [MMO coated titanium anodes, Platinised titanium anodes, Platinised niobium anodes or their copper cored with platinum plated surface] buried in the soil near the articles like underground storage tank, pipeline & etc. The current then flows on articles and returns to the rectifier through an insulated wire attached to the articles – Now the article is protected because the current passing on.
Platinised Titanium anodes take advantage of the low consumption rate and high current density. Excess of 10 Volts will result in severe pitting of the titanium core causing premature failure.
Platinized Niobium / Tantalum anodes also take advantage of the properties of platinum, but avoid the low driving voltage restriction of Platinized titanium anodes. Breakdown of the niobium oxide film occurs at approximately 120 Volts. Thus these anodes are used where high driving voltage is required. Platinized anodes are quite expensive but have an extremely long life. They are therefore an economical choice for critical applications.
Mixed Metal Oxide coated Titanium anodes consist of a high purity titanium substrate with an applied coating consisting of a mixture of platinum group metal oxides. The titanium serves as a support for the oxide coating. The mixed metal oxide is a crystalline, electrically conductive coating that activates the titanium and enables it to function as an anode. When applied on titanium, the coating has an extremely low consumption rate, measured in terms of milligrams per year. As a result of this low consumption rate, the metal dimensions remain nearly constant during the design life of the anode - providing a consistently low resistance anode. For more details, please refer www.cpanode.com
|
|
|
