Sacrificial Anodes India
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Introduction
Sacrificial anode cathodic protection (SACP) is a type of cathodic protection where a less noble material that acts as a sacrificial anode is connected by metallic conductors to the structure to be protected. A sacrificial metal is a metal used as a sacrificial anode in cathodic protection that corrodes to prevent a primary metal from corrosion or rusting. The materials used for this purpose are magnesium, aluminium and zinc. They provide electrons to the structure to be protected and are consumed.
Problem / What is at stake?
Numerous reinforced concrete structures worldwide, such as bridges and offshore platforms, are exposed to aggressive chloride environments and show evidence of corrosion after short service periods. The cost of repairing or replacing deteriorated structures has become a major liability for Government and non-Government asset owners.
The only substantiated method to arrest chloride-related corrosion of metals embedded in concrete is cathodic protection (CP).
There are two types of cathodic protection on the basis of supplying electrons to a structure:
- Sacrificial anode cathodic protection (SACP) – A less noble material acts as a sacrificial anode.
- Impressed current cathodic protection (ICCP) – An external current source and rectifier is used.
In applications such as patch repairs and other general sacrificial CP installations, localized “point” anodes are used. It is well established that repairs of chloride-contaminated or carbonated concrete can create electrochemical incompatibilities between the “new” and “old” concrete that may lead to the accelerated corrosion of the steel reinforcement in the concrete near the patch repair. This is known as the “halo” effect. The resulting corrosion can induce cracking that may require extending the patching repair after a short time period (e.g., three to five years).
The idea of the localized CP anode application is that small galvanic point anodes installed in the patch repair will sacrificially corrode and reduce the possibility of a new active corrosion zone on the surrounding rebar.
The sacrificial anodes system can be designed considering the expected service life of the structure.
Features and benefits of SACP:
- No independent source of electric power required
- Limited effects on neighbouring structures
- Anode connections are also protected
- Correct material selection ensures no over-protection, thus avoiding metal embrittlement and coating damage
- No possibility of damage due to incorrect connections
- Straightforward to install, operate and maintain
Our Expertise / How SSPIPL can help you?
SSPIPL has worked with several well-known names such as Tata Motors, Bennett Coleman and Co. Ltd. (Times of India), Siemens Limited, Goa State Infrastructure Development Corporation, Sterlite Technologies Limited, Bombay Hospital Trust, Uttar Pradesh Rajkiya Nirman Nigam Limited, Tata Motors Limited, Watson Pharma, Lubrizol India Private limited, Nagpur Improvement Trust, Mumbai Port Trust, Axis Bank, Consulate General of the federal republic of Germany Mumbai, Peninsula Land Limited, ACC Limited (ACC Cement), Larsen and Toubro and many others.
SSPIPL is a leading specialist contractor that has undertaken & successfully completed major projects in all major cities of India. SSPIPL can cater to cities like Mumbai, Delhi, Kolkata, Bangalore, Hyderabad, Chennai, Bhopal, Bhubaneswar, Chhattisgarh, Raipur, Gandhinagar, Lucknow, Patna, Ranchi, Gangtok, Dehradun, Chandigarh, Shimla & Srinagar.