Industrial Coatings South Africa | Silicone Coating Solutions for Mining, Infrastructure and Power
Technical Solutions Supplies is Southern Africa’s leading distributor of high performance silicone industrial coatings. We supply protective coating systems for mining, infrastructure, power utilities and industrial facilities throughout South Africa, Namibia, Botswana, Zimbabwe, Zambia and the broader Southern African region.
Our silicone coatings outperform traditional systems including epoxy, polyurethane and acrylic in every critical performance category. Consequently, asset owners across Southern Africa choose silicone for applications where conventional coatings consistently fall short.
Why Industrial Coatings Fail in Southern Africa
Southern Africa’s climate is one of the most demanding coating environments on earth. Intense UV radiation degrades organic coating resins faster than temperate climate data sheets predict. Wide daily temperature swings on the highveld generate constant thermal stress that cracks rigid coating films. Coastal salt aerosol in KwaZulu-Natal and the Western Cape attacks conventional coatings at the molecular level. Industrial pollution from decades of mining and heavy industry deposits aggressive contaminants on every exposed surface.
Traditional industrial coatings were developed for temperate climates. They underperform in Southern Africa because the chemistry was not designed for these conditions. Silicone was.
Understanding Surface Preparation Standards: St2, St3 and Sa2.5
One of the most searched questions in industrial coating specification is what coating system works when full abrasive blast cleaning to Sa2.5 is not achievable. This is a common problem on maintenance projects worldwide.
ISO 8501-1 defines the internationally recognised surface preparation standards for steel. Blast cleaning standards use the Sa designation, ranging from Sa1 light blast cleaning to Sa3 white metal. Hand and power tool cleaning standards use the St designation, with St2 and St3 being the two recognised grades.
St2 is thorough hand and power tool cleaning. The surface is free from visible oil, grease, dirt and poorly adhering mill scale, rust and paint. The steel carries a slight metallic sheen after cleaning. St3 follows the same process but goes considerably further, producing a pronounced metallic sheen from the substrate.
Sa2.5 is near white metal blast cleaning. It produces a surface almost entirely free of mill scale, rust and foreign matter. Most high performance coating systems specify Sa2.5 as their minimum surface preparation requirement.
The problem is that Sa2.5 is frequently not achievable on in-service structures. On bridges, storage tanks, mining infrastructure and industrial steel in operation, abrasive blasting creates dust, requires containment, and is not practical within maintenance project constraints. Access and logistics on elevated or congested structures often make it economically unviable.
This is where conventional coating systems fail the maintenance engineer. Epoxy and polyurethane systems specify Sa2.5 because they need a high surface profile to achieve adequate adhesion. When that standard is not achievable, those systems are not viable options.
The Surface Tolerant Coating Solution: SI-COAT 579 CM
SI-COAT 579 CM is a single component moisture cure RTV silicone corrosion maintenance coating manufactured by CSL Silicones. It was specifically formulated as a surface tolerant coating for maintenance applications where Sa2.5 blast cleaning is not achievable.
SI-COAT 579 CM bonds directly to steel prepared to St2 or St3 standard under ISO 8501-1. No abrasive blasting equipment is required. Standard maintenance crews using hand tools, wire brushes, disc sanders and power tools can achieve the surface preparation standard that 579 CM needs to perform correctly.
This changes the economics and practicality of corrosion maintenance entirely. Projects that were previously deferred because blast cleaning logistics made them unviable become straightforward maintenance tasks. Structures that cannot be shut down for full blast and recoat programmes receive effective corrosion protection during planned maintenance windows using standard equipment.
The silicone chemistry in 579 CM also addresses the performance limitations that make conventional surface tolerant epoxy systems an imperfect solution. Epoxy surface tolerant coatings are more forgiving on surface preparation than standard systems, but they still degrade under UV exposure, still crack under thermal movement, and still require recoating within five to seven years in harsh outdoor environments.
SI-COAT 579 CM does not photodegrade under UV radiation. It remains permanently flexible under thermal cycling. It resists chemical attack from acids, alkalis and industrial pollutants. Applied once to a correctly prepared St2 or St3 surface, it delivers corrosion protection that outlasts conventional surface tolerant systems by a significant margin.
Industrial Coating Comparison: Silicone vs Traditional Systems
Understanding how coating chemistries compare helps specifiers and asset owners make the right system choice for their application and environment.
Epoxy coatings provide good chemical resistance and adhesion to steel and concrete. However, they require Sa2.5 surface preparation for optimal performance, degrade under UV exposure through chalking and gloss loss, become brittle under thermal cycling, and have an outdoor service life of five to seven years before recoating.
Polyurethane coatings offer better UV resistance than epoxy and are commonly used as topcoats in three coat systems. However, they yellow and degrade over time under sustained UV exposure, require primer and intermediate coats, and carry a service life of five to eight years in Southern African conditions before maintenance intervention.
Acrylic coatings are economical and easy to apply. However, they degrade rapidly under ponding water through osmosis, have limited chemical resistance, and require recoating every three to five years. In Southern Africa’s UV environment, the service life is shorter still.
Silicone coatings address the fundamental failure mechanisms that limit conventional systems. The silicon oxygen backbone of the polymer is inherently UV stable. The permanently flexible elastomeric film accommodates thermal movement without cracking. The hydrophobic chemistry resists moisture penetration. The chemical inertness protects against acid, alkali and industrial pollutant attack. The result is a service life exceeding 20 years in environments that destroy conventional coatings in five to seven.
Four Silicone Coating Solutions for Southern African Industry
SI-COAT 579 CM: Corrosion Maintenance Coating
SI-COAT 579 CM is a surface tolerant silicone corrosion maintenance coating for structural steel, storage tanks, bridges, mining infrastructure and industrial equipment. It applies directly to St2 and St3 prepared surfaces without abrasive blasting, making it the practical choice for in-service maintenance projects worldwide.
Suitable environments include mining operations, petrochemical facilities, coastal industrial structures, bridges and overpasses, and any steel infrastructure where Sa2.5 blast cleaning is not achievable.
Learn more about SI-COAT 579 CM
SI-COAT 461 RC: Silicone Roof Coating
SI-COAT 461 RC is a 100% silicone roof coating for industrial and commercial flat roofs. It resists continuous ponding water, which eliminates it from the category of acrylic and polyurethane roof coatings that fail under sustained water immersion. High solar reflectivity reduces cooling costs on large industrial buildings. Service life exceeds 20 years where acrylic products require recoating every three to five years.
Learn more about SI-COAT 461 RC
SI-COAT 570 HVIC: High Voltage Insulator Coating
SI-COAT 570 HVIC prevents pollution flashover on high voltage insulators, transformers, switchgear and substation equipment. The permanently hydrophobic silicone film stops conductive moisture films forming on contaminated insulator surfaces, eliminating the leakage current and dry band arcing that leads to flashover. Applicable live-line without taking equipment out of service. Service life exceeds 15 years in Southern African utility environments.
Learn more about SI-COAT 570 HVIC
CSL 316: Self Levelling Silicone Joint Sealant
CSL 316 is an ASTM C920 Class 50 silicone joint sealant for horizontal concrete expansion joints on roads, bridges, airports, harbours and industrial floors. It accommodates plus or minus 50% joint movement, double the capability of standard polyurethane sealants, and carries a 20 year service life where polyurethane products require replacement every five to seven years under Southern Africa’s UV conditions.
Industries Served Across Southern Africa
Technical Solutions Supplies serves asset owners, engineers, contractors and maintenance teams across a wide range of industries throughout Southern Africa.
Mining and mineral processing operations in South Africa, Zambia, Botswana, Namibia and the DRC face some of the most aggressive corrosion environments in the world. Sulphuric acid from copper processing, salt spray in coastal mining operations, and abrasive dust across the Copperbelt all demand coating systems that conventional products cannot handle. SI-COAT 579 CM resists these conditions and applies to in-service infrastructure without the blast cleaning that operational mining environments cannot accommodate.
Power generation and electrical utilities across Southern Africa struggle with pollution flashover on transmission and distribution infrastructure. Salt spray, industrial emissions and dust accumulate on insulator surfaces, creating the conductive pathways that cause outages and equipment damage. SI-COAT 570 HVIC eliminates flashover risk and applies live-line to energised equipment.
Infrastructure and transportation including roads, bridges, airports and harbours requires joint sealants and protective coatings that perform across decades rather than years. CSL 316 meets SANRAL specifications for South African highway projects and delivers the movement capability that bridge and road infrastructure demands.
Industrial and commercial facilities including warehouses, logistics centres, manufacturing plants and shopping centres require roof waterproofing that withstands ponding water and UV degradation. SI-COAT 461 RC delivers permanent waterproofing where acrylic systems consistently fail.
Chemical and petrochemical facilities including tank farms, refineries and process plants require coatings that resist acid, alkali and solvent attack. SI-COAT 579 CM provides chemical resistance that conventional systems cannot match at the surface preparation standards that in-service maintenance allows.
Lifecycle Cost: Why Silicone Costs Less Over Time
Silicone coatings carry a higher initial cost than epoxy and polyurethane systems. The lifecycle cost calculation tells a different story.
A conventional epoxy or polyurethane coating system on an industrial structure in Southern Africa requires recoating every five to seven years. Each recoating cycle generates surface preparation costs, material costs, application labour costs, scaffolding and access costs, and production downtime costs. Over 20 years, a conventional system generates three full recoating cycles. A silicone system applied once delivers the same or better protection across the full 20 year period with no recoating required.
Total lifecycle cost for silicone is consistently 40 to 60 percent lower than conventional systems over a 20 year period when all recoating and downtime costs factor into the calculation.
Standards and Compliance
SI-COAT 579 CM achieves C5-M and C5-I corrosion protection per ISO 12944-6 when applied over zinc phosphate epoxy primer, meeting the most stringent international standards for marine and industrial corrosion environments. Applied directly to St2 or St3 prepared steel, it provides corrosion resistance suitable for C3 and C4 corrosivity categories per ISO 12944.
CSL 316 meets ASTM C920 Type M Grade P Class 50 and COTO specifications for SANRAL approved road and bridge infrastructure projects in South Africa.
All products are manufactured by CSL Silicones and distributed exclusively in Southern Africa by Technical Solutions Supplies.
Frequently Asked Questions
What is a surface tolerant coating and when is it needed?
A surface tolerant coating is a protective coating system formulated to adhere and perform on steel that has not been abrasive blast cleaned to Sa2.5. Surface tolerant coatings are used when blast cleaning is not achievable due to access constraints, operational requirements, environmental regulations or logistics on in-service structures. SI-COAT 579 CM is a surface tolerant silicone coating that bonds to steel prepared to St2 or St3 standard under ISO 8501-1, without requiring abrasive blasting equipment.
What coating can be applied to steel cleaned only to St2 or St3?
SI-COAT 579 CM silicone corrosion maintenance coating applies directly to steel prepared to ISO 8501-1 St2 or St3 standard using hand tools and power tools. No abrasive blast cleaning to Sa2.5 is required. This makes it the practical corrosion protection solution for in-service bridges, storage tanks, mining structures, industrial steel and any application where blast cleaning is not feasible.
What is the difference between St2, St3 and Sa2.5 surface preparation?
St2 and St3 are hand and power tool cleaning standards under ISO 8501-1. St2 is thorough cleaning that removes poorly adhering mill scale, rust and paint, leaving a slight metallic sheen. St3 is very thorough cleaning that goes further, producing a pronounced metallic sheen. Both use wire brushes, disc sanders, needle guns and power tools. Sa2.5 is near white metal blast cleaning achieved with abrasive blasting equipment, which produces a much cleaner surface with a defined anchor profile. Most conventional high performance coatings require Sa2.5. SI-COAT 579 CM performs correctly from St2 upward.
Can you apply a corrosion coating without sandblasting?
Yes. SI-COAT 579 CM applies to steel prepared by hand tool or power tool cleaning to St2 or St3 standard under ISO 8501-1 without sandblasting or abrasive blasting. This makes effective corrosion protection achievable on in-service structures, bridges, mining infrastructure and industrial equipment where abrasive blasting is not practical.
Why do most industrial coatings require Sa2.5 surface preparation?
Conventional coating systems such as epoxy and polyurethane rely on a high anchor profile created by abrasive blasting to achieve adequate adhesion to the steel substrate. Without that profile, adhesion is insufficient and the coating fails prematurely. SI-COAT 579 CM uses silicone chemistry that bonds effectively to hand and power tool cleaned surfaces at St2 and St3 standard because the silicone polymer adheres through a different mechanism that does not depend on the deep anchor profile that epoxy systems require.
How long does a silicone corrosion coating last compared to epoxy?
In harsh outdoor environments including coastal, industrial and high UV conditions, SI-COAT 579 CM provides a service life exceeding 20 years. Epoxy systems in the same environments typically require recoating every five to seven years. Polyurethane systems carry a similar service life of five to eight years. Over a 20 year asset life, silicone delivers total lifecycle costs 40 to 60 percent lower than conventional systems when recoating, labour, access and downtime costs factor into the calculation.
What is the best industrial coating for coastal environments in Southern Africa?
For coastal industrial environments in Southern Africa, a 100% silicone coating system such as SI-COAT 579 CM for structural steel or SI-COAT 461 RC for flat roofs provides the most durable long term protection. Silicone is inherently resistant to chloride attack, does not hydrolyse in high humidity marine conditions, and does not degrade under UV radiation. These properties make it specifically suited to the high salt, high UV, high humidity coastal environments in KwaZulu-Natal, the Western Cape and coastal Namibia.
What is the best coating for steel storage tanks in mining operations?
SI-COAT 579 CM silicone corrosion maintenance coating provides superior protection for steel storage tanks in mining environments. It resists sulphuric acid from copper processing, handles salt spray in coastal mining operations, and applies to St2 or St3 prepared surfaces without blast cleaning. This is particularly important in operational mining environments where tanks cannot be taken out of service for full blast and recoat programmes.
What industrial coating is suitable for bridges without abrasive blasting?
SI-COAT 579 CM is the recommended corrosion maintenance coating for bridges and overpasses where abrasive blasting is not achievable. It bonds to steel prepared to St2 or St3 standard, applies in a single coat without primer, remains permanently flexible to accommodate structural movement, and provides UV stable corrosion protection for a service life that significantly exceeds conventional bridge paint systems. It meets the practical constraints of bridge maintenance where access, traffic management and blast containment make Sa2.5 surface preparation unachievable.
Does silicone coating work on previously painted steel?
Yes. SI-COAT 579 CM can be applied over previously painted steel where the existing coating has sound adhesion to the substrate. Areas of active delamination, blistering or poorly adhering paint should be removed to the St2 or St3 standard before application. The chemical inertness of silicone means it does not react adversely with most existing coating systems.
What coating prevents flashover on high voltage insulators?
SI-COAT 570 HVIC is an RTV silicone high voltage insulator coating that prevents pollution flashover on transmission and distribution insulators, transformer bushings, switchgear and substation equipment. The permanently hydrophobic silicone film prevents conductive moisture films forming on contaminated insulator surfaces, stopping the leakage current and dry band arcing that leads to flashover. It applies live-line to energised equipment and carries a service life exceeding 15 years in Southern African utility environments.
What is the best flat roof coating for industrial buildings in South Africa?
SI-COAT 461 RC silicone roof coating is the most appropriate system for industrial flat roofs in South Africa. Unlike acrylic based products, silicone does not absorb water under ponding conditions, does not degrade under UV radiation, and does not crack under thermal cycling. It delivers a service life exceeding 20 years where acrylic systems require recoating every three to five years. It applies to concrete, metal, modified bitumen, EPDM, TPO and polyurethane foam substrates.
How do I choose the right industrial coating system for my project?
The correct coating system depends on the substrate type, the corrosivity category of the environment, the surface preparation achievable on the project, the expected service life, and the lifecycle cost requirements. Technical Solutions Supplies provides coating specification support for projects of all sizes across Southern Africa. Contact our team for project specific recommendations and technical assistance.
Contact Technical Solutions Supplies
Phone: 031 002 7376 Email: sales@tssupplies.co.za
We provide technical specifications, product samples, contractor training and on-site support for industrial coating projects throughout Southern Africa. Proud distributors of CSL Silicones products across the region.
