Active Protection against Corrosion

Depletion of oxygen in near stagnant fluid in crevices drops the pH balance – which sets up an electrochemical concentration cell, called a differential aeration cell – and extended periods of moisture and conductive contaminant runoff onto foundation assemblies should raise the alarm as it spells only one thing: your substation (SS) foundations are threatened by crevice corrosion.

Currently, concrete plinths and metal assemblies (supporting lattice, transformers, switchgear etc.) are not adequately protected with an active seal. Solving exacerbated SS foundation assembly corrosion is not a simple process, requiring innovative technology. A sealant – compatible with concrete and galvanising – that forms a homogenous seal over the entire concrete and metal assemblies is provided by Afrisun Coating Enterprises. This is generically referred to as a High Ratio Calcium Sulfonate Alkyd (HRCSA). The AFRISUN-HRCSA™ provides active protection of critical assets for decades and is now implemented as a sealant system by South Africa’s state-owned utility, Eskom.

In collaboration with high performance coatings experts and Eskom, the following queries are deemed important:

Q: IF YOUR FOUNDATIONS ARE CORRODING, CAN THIS ACTIVE SEAL STOP THE CORROSION FROM CONTINUING?

A: Yes. The red penetrant seeps into crevices through capillary action, displaces moisture and oxygen and passivates the metal crevices by lifting the pH to >10.1. Overcoat of the concrete and metal assemblies with the self-priming, thixotropic, hydrophobic, non-conductive grey topcoat/sealant also passivates the substrates by lifting the pH >10.1.

Q: FROM AN ENGINEERING PERSPECTIVE, WHEN SPECIFYING A HOLD POINT FOR NEW SS PROJECTS, SHOULD THIS SEALANT SYSTEM BE APPLIED TO THE FOUNDATIONS ABOVE GRADE BEFORE   ERECTING THE SS EQUIPMENT?

A: Yes. The sealant will cure to a firm finish within 28 days but the erection of the structures can commence immediately after application. As mechanical damage will occur, a simple touch-up

with a paint brush is required, which will fuse into the already applied AFRISUN-HRCSA™  .

In doing so, there is no direct contact between the concrete and the equipment.

Q: WHEN UNDESIRABLE FOUNDATION SURFACE CONDITIONS SUCH AS CRACKS OR A CONCAVE FINISH OF THE HORIZONTAL SURFACE IS SEEN, CAN THIS SEALANT ELIMINATE THESE DEFECTS?

A: AFRISUN-HRCSA™   is the ideal solution as the red penetrant seeps into the cracks rendering the micro-environment passive and the grey topcoat/sealant is over coated, filling all cracks. In the event of concave horizontal surfaces that cause ponding of water, the grey topcoat/sealant is poured over the horizontal surface of all foundations until it has levelled out to a flat finish, eliminating ponding. Bearing in mind that the AFRISUN-HRCSA™ is also hydrophobic and contains Calcite, a constituent of Portland cement, the ideal solution is finally available. HRCSA active seal technology reacts with the surface of the metal, changing the environment on the surface to protect the steel. AFRISUN-HRCSA™ has passed a rigorous test conducted by Eskom for two years in the most corrosive environment in South Africa with great success. With minimal surface preparation, AFRISUN- HRCSA™ provides a cost-effective, long lifecycle, active sealant for all your SS foundations.

“Solving exacerbated SS foundation assembly corrosion is not a simple process, requiring innovative technology.”

Please have look at the following hyperlink:

http://spintelligentpublishing.com/Digital/ESI-Africa/african-power-elites-2018/index.html  and the article published on page 68 titled Active Protection Against Corrosion.

Substations

Active Protection against Corrosion

Depletion of oxygen in near stagnant fluid in crevices drops the pH balance – which sets up an electrochemical concentration cell, called a differential aeration cell – and extended periods of moisture and conductive contaminant runoff onto foundation assemblies should raise the alarm as it spells only one thing: your substation (SS) foundations are threatened by crevice corrosion.

Currently, concrete plinths and metal assemblies (supporting lattice, transformers, switchgear etc.) are not adequately protected with an active seal. Solving exacerbated SS foundation assembly corrosion is not a simple process, requiring innovative technology. A sealant – compatible with concrete and galvanising – that forms a homogenous seal over the entire concrete and metal assemblies is provided by Afrisun Coating Enterprises. This is generically referred to as a High Ratio Calcium Sulfonate Alkyd (HRCSA). The AFRISUN-HRCSA™ provides active protection of critical assets for decades and is now implemented as a sealant system by South Africa’s state-owned utility, Eskom.

In collaboration with high performance coatings experts and Eskom, the following queries are deemed important:

Q: IF YOUR FOUNDATIONS ARE CORRODING, CAN THIS ACTIVE SEAL STOP THE CORROSION FROM CONTINUING?

A: Yes. The red penetrant seeps into crevices through capillary action, displaces moisture and oxygen and passivates the metal crevices by lifting the pH to >10.1. Overcoat of the concrete and metal assemblies with the self-priming, thixotropic, hydrophobic, non-conductive grey topcoat/sealant also passivates the substrates by lifting the pH >10.1.

Q: FROM AN ENGINEERING PERSPECTIVE, WHEN SPECIFYING A HOLD POINT FOR NEW SS PROJECTS, SHOULD THIS SEALANT SYSTEM BE APPLIED TO THE FOUNDATIONS ABOVE GRADE BEFORE   ERECTING THE SS EQUIPMENT?

A: Yes. The sealant will cure to a firm finish within 28 days but the erection of the structures can commence immediately after application. As mechanical damage will occur, a simple touch-up

with a paint brush is required, which will fuse into the already applied AFRISUN-HRCSA™  .

In doing so, there is no direct contact between the concrete and the equipment.

Q: WHEN UNDESIRABLE FOUNDATION SURFACE CONDITIONS SUCH AS CRACKS OR A CONCAVE FINISH OF THE HORIZONTAL SURFACE IS SEEN, CAN THIS SEALANT ELIMINATE THESE DEFECTS?

A: AFRISUN-HRCSA™   is the ideal solution as the red penetrant seeps into the cracks rendering the micro-environment passive and the grey topcoat/sealant is over coated, filling all cracks. In the event of concave horizontal surfaces that cause ponding of water, the grey topcoat/sealant is poured over the horizontal surface of all foundations until it has levelled out to a flat finish, eliminating ponding. Bearing in mind that the AFRISUN-HRCSA™ is also hydrophobic and contains Calcite, a constituent of Portland cement, the ideal solution is finally available. HRCSA active seal technology reacts with the surface of the metal, changing the environment on the surface to protect the steel. AFRISUN-HRCSA™ has passed a rigorous test conducted by Eskom for two years in the most corrosive environment in South Africa with great success. With minimal surface preparation, AFRISUN- HRCSA™ provides a cost-effective, long lifecycle, active sealant for all your SS foundations.

“Solving exacerbated SS foundation assembly corrosion is not a simple process, requiring innovative technology.”

Please have look at the following hyperlink:

http://spintelligentpublishing.com/Digital/ESI-Africa/african-power-elites-2018/index.html  and the article published on page 68 titled Active Protection Against Corrosion.