Single-pack direct-to-metal (DTM) one-coat system that actively bonds and neutralizes structural surfaces, formulated to substitute primer, intermediate and topcoat configurations adhering to international environmental protection policies.
Recognized as the top-performing one-coat system in Federal Highway Administration (FHWA) tests since the 1980s, HRCSA was introduced as an overcoating (encapsulating) system as an alternative to traditional primer, intermediate and topcoat configurations, eliminating the need for sweep or grit blasting while also being acknowledged as ideal for zone coating. The technology cuts project overheads, reduces surface preparation and product application time, and preserves site conditions, resulting in minimal environmental pollution.
Active Interfacial Neutralization
RUSTOPAK® High Ratio Calcium Sulfonate Alkyd (HRCSA) anti-corrosion coating is a highly engineered, single-component polymer architecture that chemically alters the interfacial environment to actively inhibit corrosion. As an over-based sulfonate-carbonate complex widely recognised as a bridge maintenance overcoating system the product is applied onto zinc bearing steel (Hot Dip Galvanizing), direct to metal (DTM) onto un-galvanised metal that is not corroding or over tightly adherent corrosion. The HRCSA by formulation is highly effective in encapsulating tightly adherent weathered coatings as a one coat high-performance solution to protect assets managed by many Departments of Transport (DOT) throughout the US.
Active Interfacial Neutralization
RUSTOPAK® High Ratio Calcium Sulfonate Alkyd (HRCSA) one coat active corrosion mitigation coating system is single-component polymer architecture that chemically alters the interfacial environment to actively inhibit corrosion. As an over-based sulfonate-carbonate complex formulated as a bridge maintenance overcoating system, the product is applied to zinc bearing steel (Hot Dip Galvanized), un-galvanised metal with tightly adherent corrosion and where grit blasting is still being specified. The HRCSA encapsulates tightly adherent weathered coatings, actively sealing off assets that are managed by Departments of Transport (DOT) throughout the US.
STOP RUST HERE
Applied onto low-traffic surfaces, HRCSA bonds to and neutralises the following substrates.
Direct-to-metal application to smooth or weathered hot-dip galvanised surfaces.
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Bonding to the surface
HRCSA bonds through a coordinating mechanism using electrostatic attraction, allowing direct-to-metal application to smooth or weathered zinc-coated (hot-dip galvanised) substrates.
Hydrophobic corrosion mitigation
The over-based calcium sulfonate matrix forms a thixotropic, overlapping lattice of crystalline calcite (CaCO₃) platelets. The hydrophobic, self-healing matrix seals the treated surface from moisture, inhibiting sacrificial zinc consumption.
Active neutralisation
The supplied formulation description identifies an alkaline sulfonate-carbonate complex that raises the surface pH to ≥ 10.1 and actively neutralises the treated surface.
02
Electroplated metal components
Included among the substrates listed for low-traffic applications.
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Application scope
Electroplated metal components are included in the supplied list of substrates. RUSTOPAK® bonds to and neutralises these substrates when applied onto low-traffic surfaces.
03
Ungalvanised steel, rust-free
Direct-to-metal corrosion mitigation for rust-free ungalvanised steel.
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Suitable substrate
The supplied Top Coat description includes direct-to-metal application onto ungalvanised metal that is not corroding.
Surface condition
Surfaces must be completely dry and free of contaminants, including oil, grease, salt and dirt, prior to application.
04
Ungalvanised steel with tightly adherent rust
Treatment of steel where corrosion remains tightly attached.
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Tightly adherent corrosion
The supplied Top Coat description states that total removal of tightly adherent corrosion is not required. Tightly adherent rust on structural steel must be completely dry and free of contaminants, including oil, grease, salt and dirt, prior to application.
Hard-to-reach areas
RUSTOPAK® Penetrant (Aerosol) is designed for wetting into hard-to-reach areas. Capillary action enables the product to wick into crevices without dismantling structures. The supplied system instructions pair the Penetrant with RUSTOPAK® Top Coat.
05
Firmly adherent coatings
Overcoating of compatible, tightly adherent weathered coatings.
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Coating compatibility
The supplied Top Coat instructions allow direct application over compatible, tightly adherent weathered coatings and refer to a specific approved coating list.
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KEY FEATURES
How RUSTOPAK® HRCSA Delivers Active Corrosion Mitigation
01
Electrostatic Bonding Mechanism
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High Ratio Calcium Sulfonate Alkyd bonds through a strong coordinating mechanism, using electrostatic attraction, allowing direct-to-metal (DTM) application to smooth or weathered zinc-coated (hot-dip galvanized) substrates also adhering to metals, oxides and compounds on weathered structures unlike conventional primer, intermediate and topcoat systems, which obtain adhesion through hydroxyl, carboxyl and epoxide groups which usually requires a substrate profile achieved by grit or sweep blasting to create a profile for primer coat mechanical interlocking.
The direct to metal (DTM) product, due to van der Waals forces has a greater attraction to metal than water, as its primary method of adhesion, not requiring grit or sweep blasting for mechanical interlocking adhesion to metal surfaces before coating. Modified calcium sulfonate/carbonate complexes obtain adhesion through charge attraction. The positively charged calcium and double bonded oxygen’s have a strong affinity for the negatively charged metal surfaces, a different adhesion mechanism to conventional coating systems that obtain adhesion through hydroxyl, carboxyl and epoxide groups which usually requires a substrate profile achieved by grit or sweep blasting. The modified calcium sulfonate system is not affected by the ions generated during the corrosion process that normally causes undercutting.
In molecular physics, the van der Waals forces are distance-dependent interactions between atoms or molecules. Unlike ionic or covalent bonds, these attractions are not a result of any chemical electronic bond and they are comparatively weak and more susceptible to being disturbed. Van der Waals forces quickly vanish at longer distances between interacting molecules. Van der Waals forces also define many properties of organic compounds and molecular solids, including their solubility in polar and non-polar media.
Polarity
The polarity of the aromatic ring and attached sulfonate (SO3) group results in a product with superb metal wetting and moisture displacement properties. The polar end of the sulfonate/carbonate complex attaches to metallic substrates and demonstrates exceptional adhesion even when the film is damaged. Very thin films of only a few mils (1 mil = 25.4 µm) can offer up to 1,000 hours of corrosion mitigation in the ASTM B 117 Salt Fog Test. The moisture displacement property allows the application of the product in less than optimal conditions.
02
Active Surface Neutralization
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High Ratio Calcium Sulfonate Alkyd stops corrosion cell formation through an active sulfonate-carbonate complex. Its dense, alkaline core continuously raises the surface pH ≥ 10.1 actively neutralizing both metal and zinc-coated (hot-dip galvanized) substrates, preventing further oxidation.
Neutralization and Over-Basing
Sulfonic acid is converted into the sulfonate-carbonate complex by neutralizing the sulfonic acid and reacting with the metal salt with an excess of calcium hydroxide and calcium oxide to form the over-based complex.
Interfacial Environmental Modification
The direct to metal (DTM) One-Coat product causes a neutralization reaction between the mild sulfonic acids (RSO3H) in the formulation and the zinc carbonate (ZnCO3) layer present on galvanized surfaces, producing a robust, integrated zinc sulfonate matrix. This neutralization bond, combined with the dense alkaline core of the overbased complex, permanently raises the local interfacial environment to an alkaline pH ≥ 10.1. Because zinc and carbon steel corrosion cells require an acidic environment to thrive, this sustained alkaline shift renders the environment thermodynamically too basic for corrosion formation, arresting zinc and iron oxidation and sub-film under-creep.
Corrosion Inhibition
The calcium carbonate (CaCO3) part of the complex functions primarily as an alkalinity reserve. The carbonate is slightly soluble in water and acts as a corrosion inhibitor by buffering the pH at the local metal surface. A pH ≥ 10.1 is maintained at the coating/metal interface, which delays the onset of the corrosion process and actively prevents under cutting (undercreepage), an essential characteristic of an active joint sealant.
03
Hydrophobic, Self-Healing Matrix
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The permanently hydrophobic and self-healing matrix of High Ratio Calcium Sulfonate Alkyd seals smooth or weathered zinc-coated (hot-dip galvanized) substrates inhibiting sacrificial zinc consumption and further oxidation of metals and existing compounds. This outward-facing hydrocarbon array creates a dense, non-polar hydrophobic membrane that repels moisture, ionic species and oxygen, effectively suppressing cathodic and anodic corrosion cell formation.
The hydrophobic product cures to a firm finish (ASTM D3363) of 5B Pencil Hardness and passes the (ASTM D522) 180° Mandrel Bend Test. The product remains permanently firm, accommodating Linear Coefficient of Thermal Expansion (LCTE) of the underlying steel substrate during extreme thermal fluctuations without experiencing embrittlement, micro-cracking, or delamination at structural connections.
Once the modified calcium sulfonates have “plated out” with their charged groups toward the metal they orient towards, a very hydrophobic hydrocarbon chain structure outward is established. This environment prevents water from reaching the metal as the calcite platelets increase the path length that oxygen or water would need to take to reach the metal substrate. The hydrophobicity is further increased by the chemical constituents that form the matrix between the platelets (wax, OXPET), which are also hydrophobic.
04
Surface Encapsulation
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Surface encapsulation in High-Ratio Calcium Sulfonate Alkyd is driven by the immediate chemical and physical interactions at the substrate interface. Charged polar sulfonate groups and van der Waals forces wet and anchor directly to smooth or weathered substrates without requiring abrasive sandblasting, effectively displacing moisture and encapsulating the metal at a molecular level. Simultaneously, an over-based calcium carbonate core continuously buffers the coating interface to an alkaline pH ≥10.1 creating an environment where active corrosion and sub-film under-creep are thermodynamically unable to form.
Beyond interfacial bonding and neutralization, long-term encapsulation relies on the matrix's structural durability and protective shield. Outward-oriented hydrocarbon chains and aligned calcite platelets form a dense, hydrophobic barrier that blocks moisture and oxygen ingress while remaining permanently flexible to accommodate structural thermal expansion without cracking. Combining an organic sulfonate backbone with an inorganic colloidal calcium core yields an organic-inorganic hybrid system that, when applied over hot-dip galvanizing, provides a synergistic duplex effect extending service life by 1.5 to 2.5 times protected by integrated UV inhibitors that prevent surface degradation under severe solar exposure.
05
Hybrid Duplex Corrosion Mitigation
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High Ratio Calcium Sulfonate Alkyd is an organic-inorganic hybrid (sulfonate organic and calcium inorganic complex) duplex coating that actively delivers extended corrosion mitigation for zinc-coated (hot-dip galvanized) substrates.
Standards - HDGASA
ISO 1461 International Standard for hot dip galvanizing (zinc-coated substrates) - ISO 1461 refers to ISO 12944 Duplex coating of hot dip galvanizing (zinc-coated substrates). ISO 12944 “Duplex" system combines hot-dip galvanizing with an organic paint or powder coating. This pairing creates a powerful, synergistic effect where the life expectancy of the combined system is generally (1.5 to 2.5) times the lifespan of either system used independently.
Over-Based Calcium Sulfonate
High Ratio Calcium Sulfonate is an organic-inorganic hybrid rather than purely organic or purely inorganic product. The base structure of the product relies on an organic sulfonate component. To achieve superior anti-corrosion and water-resistant properties, the product is over-based. Excess calcium (an inorganic metal) is added to form a colloidal suspension of inorganic calcium carbonate (CaCO3) held in a lattice by the organic sulfonate.
Interfacial Environmental Modification
The direct to metal (DTM) One-Coat RUSTOPAK® product causes a neutralization reaction between the mild sulfonic acids (RSO3H) in the formulation and the zinc carbonate (ZnCO3) layer present on galvanized surfaces, producing a robust, integrated zinc sulfonate matrix. This neutralization bond, combined with the dense alkaline core of the overbased complex, permanently raises the local interfacial environment to an alkaline pH ≥ 10.1. Zinc and carbon steel corrosion cells require an acidic environment to thrive, this sustained alkaline shift renders the environment thermodynamically too basic for corrosion formation, arresting zinc and iron oxidation and sub-film under-creep.
This complex is dispersed in Mineral Turpentine/Spirits and exhibits a variety of properties, which relate to the chemical structure of over-based gelled calcium sulfonate. These include hydrophobicity due to platelet formation, polarity and corrosion inhibition. The calcium sulfonate resin provides the excellent corrosion resistance, water resistance, adhesion to bare metal and hot dip galvanized steel.
06
Integrated UV Damage Mitigation
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High Ratio Calcium Sulfonate Alkyd incorporates proprietary UV damage mitigation technology. Formulated for long-term exposure within extreme solar radiation parameters, this technology ensures longevity of the active overcoating system.
The UV damage mitigation technology is formulated to help mitigate the adverse effects of prolonged ultraviolet (UV) radiation on the coating film, including UV-induced degradation, surface deterioration, loss of protective properties, and premature coating ageing. By supporting the integrity of the coating's protective film, the product’s integrated proprietary UV damage mitigation technology contributes to the sustained performance of the corrosion mitigation system throughout its intended service life particularly where infrastructure such as utility-scale solar park installations are subjected to elevated solar radiation, temperature fluctuations and outdoor weathering.
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RUSTOPAK® Penetrant (Aerosol) is a low-VOC, single-component penetrating liquid designed for superior wetting into hard-to-reach areas.
Used in conjunction with RUSTOPAK® Top Coat, it eliminates the need to dismantle and reassemble components during treatment.
01
Wetting and penetration
Reaches deep into tight crevices where zinc corrosion is accelerated and joints are corroding.
02
Access without dismantling
Treats hard-to-reach areas directly, saving labour and time.
03
Used with Top Coat
Used in conjunction with RUSTOPAK® Top Coat to treat inaccessible areas.
Select a heading to explore the technical detail.
Penetration and corrosion-prone areas
Specially formulated to treat inaccessible areas prone to differential aeration, bimetallic and crevice corrosion through its polar formulation and neutralisation to pH 10.1.
Capillary action enables the product to wick deep into areas that are hard to reach without dismantling structures, displacing moisture and oxygen and encapsulating the treated micro-environment.
At the same time, it neutralises the interfacial surfaces where zinc from hot-dip galvanising is depleted and rust causes damage to critical sections of structures.
Solar mounting structures
Utility-scale solar mounting structures are an example of where active corrosion mitigation is needed before the application of RUSTOPAK® Top Coat to stop accelerated corrosion of zinc.
Engineers should identify the areas on structures where corrosion initiates first.
Crevice application
Spray applied directly into hard-to-reach crevices over tightly adherent pack rust (exfoliation corrosion).
Top Coat
Overview
RUSTOPAK® Top Coat is a single-component, specially formulated active sealant system designed as a high-performance, direct-to-metal (DTM), one-coat anti-corrosion coating.
It features low volatile organic compound (VOC) emissions.
No need for total removal of tightly adherent corrosion.
03
Weathered coatings
Direct application over compatible, tightly adherent weathered coatings. Refer to the specific approved coating list.
Select a heading to view preparation and application details.
Surface preparation
Tightly adherent rust on structural steel must be completely dry and free of contaminants, including oil, grease, salt and dirt, prior to application.
Application method
System pair: Overcoat directly onto RUSTOPAK® Penetrant (Aerosol).
Technique: Apply using a wet-on-wet application method.
Application & Quality Control
Application Conditions
Select a heading to view the application requirements.
Rain
Apply only when no rain is anticipated on the day of application and the surfaces are completely dry.
Wind
Wind speed must be low during spray application. If the wind speed is too high, use roller or brush application. Overspray must be contained using suitable protection such as wind fencing, tarpaulins and drop-out sheeting.
If overspray lands on equipment that is not specified to be coated, it is the applicator’s responsibility to remove it using mineral turpentine and a clean cloth.
Temperature and climatic checks
Surface temperatures between -7 °C and 54 °C can be coated. The surface temperature must be at least 3 °C above the dew point. If the difference is less than 3 °C, condensation may form on the substrate.
For coating application, the surfaces must be completely dry.
Climatic readings are a hold point and must be inspected by a qualified coating inspector or supervisor using appropriate equipment such as a dew point meter. Readings of climatic conditions must be submitted through www.rustopak.com.
The thermodynamic instability of metals drives corrosion. Many metals occur naturally as stable, lower-energy compounds in ores. Extracting them requires energy, leaving the refined metal in a higher-energy state relative to those compounds. Under suitable environmental conditions, metals react to form more stable compounds. In atmospheric corrosion, this electrochemical process requires a corrosion cell. Moisture, oxygen, salts and differences in electrical potential can support corrosion-cell activity at joints, fasteners, crevices and weathered steel surfaces. Visible rust is often only the final sign of activity that began beneath or between connected surfaces.
This guide identifies key forms and causes of corrosion to assist with on-site corrosion mitigation assessments and how RUSTOPAK® HRCSA technology serves as the definitive, targeted solution across all applications.
Corrosion is a naturally occurring phenomenon commonly defined as the deterioration of a substance (usually a metal) or its properties because of a reaction with its environment. The tendency of a metal to corrode depends on the grain structure of the metal, its composition as formed during alloying and the temperature or deformation of a single metal surface developed during fabrication.
Corrosion occurs as a result of an electrochemical reaction driven by a potential difference between two electrodes, an anode and a cathode connected by an electronic path and immersed in a shared electrolyte. Addressing complex galvanic cells or widespread uniform corrosion where a multitude of microscopic anodic and cathodic sites form across a metal surface.
No matter the corrosion mechanism or surface complexity, RUSTOPAK® HRCSA technology disrupts electrochemical pathways to stop corrosion at the source as the definitive long term active corrosion mitigation solution.
02
Thermodynamic Instability
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At its root, corrosion is simply extractive metallurgy running in reverse. Most refined metals do not exist natively in nature because their elemental, zero-valence state (M0) is thermodynamically unstable under ambient Earth conditions.
Metals are extracted from mineral ores (oxides, sulfides, carbonates) by supplying vast amounts of thermal and electrical energy to overcome the low chemical potential of the native ore. Once exposed to oxygen, water, or other oxidizers, the refined metal sits at an artificially elevated free energy state.
Thermodynamic instability represents the energetic "driving force" that compels metals to spontaneously release this stored energy and revert to lower-energy, oxidized compound forms.
The Process
Iron atoms (Fe) [Anode] oxidize on the surface of steel, passing two electrons forming ferrous ions (Fe2+) to oxygen (O2) and moisture (H2O), forming hydroxide ions (OH−) which combines to form iron hydroxide (Fe(OH)2), further oxidized by oxygen producing hydrated iron oxide (Fe2O3 · H2O).
03
Corrosion Cell
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Corrosion cells on a metal surface is the flow of electric current that occurs between the metal surface and an electrolyte with which it is in contact, sufficient to cause the metal to degrade. Coating films are used to control one of these elements - the electrolyte. Applying protective films over the surface of the metal and isolating those points with different potential (anode and cathode) controls corrosion.
Corrosion cells can be created through:
Electrolysis
Oxygen concentration cells
Galvanic action
The driving force behind a corrosion cell is a potential or voltage difference between the anode and cathode (two or more metals) where the surfaces are in direct contact. A corrosion cell consists of four fundamental elements that affect the severity of corrosion:
Anode
Cathode
Conducting environment for ionic movement (electrolyte)
Electrical connection between the anode and cathode for the flow of current
Corrosion cells develop on the molecular scale. These cells are usually produced by three factors:
Irregularities in the metal's surface produced by the original metalworking/forming or extruding
Differences in the composition of the metal's surface pressed into the surface by shaping/rolling or finishing operations
Stresses induced from forming, welding, etc.
04
Galvanic Corrosion
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Galvanic corrosion occurs when two dissimilar, electrically connected metals are exposed to moisture; the less noble (more active) metal acts as the anode and corrodes preferentially to protect the noble cathode, driven by their potential difference on the galvanic series.
With industrial structures the classic case is a stainless-steel bolt, washer or bracket fastened into galvanized carbon steel. The cathodic stainless coupled to an anodic zinc/steel area produces an unfavourable area ratio and a concentrated corrosion ring forms around the fastener exactly where clamping force and seal integrity matter most.
Strategies: minimize the cathode-to-anode area ratio, electrically isolate metals using non-conductive gaskets and washers, select compatible metals close on the galvanic series, or completely seal multi-metal connections from electrolytes. Applying the RUSTOPAK® HRCSA technology provides permanent hydrophobicity and raises surface pH 10.1 too basic for corrosion to continue.
05
Differential Aeration Corrosion
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Differential aeration corrosion is a type of corrosion that occurs when oxygen concentrations vary across a metal's surface. The varying concentration of oxygen creates an anode and a cathode on the metal's surface.
Oxidation then occurs because an anode and a cathode have been established on the surface. In differential aeration corrosion, the area with the higher oxygen concentration becomes the cathode and area with the lower oxygen concentration becomes the anode.
Consequently, the portion of the metal that has the lower oxygen concentration is the portion subject to corrosion because the stagnant, oxygen-depleted zone inside creviced joints becomes highly anodic. To maintain charge neutrality within the occluded cell, accumulating metal ions trigger hydrolysis reactions. This process strips hydroxide ions and generates free hydrogen ions (H+), rapidly establishing a localized, self-sustaining acidic microenvironment.
Zinc carbonates, including hydrozincite, become highly soluble in this acidic regime (typically below pH 6.0) and quickly dissolve. Once this protective zinc carbonate (ZnCO3) layer is destroyed, it causes the underlying pure zinc and subsequent alloy sub-layers to be consumed, resulting in the termination of cathodic protection.
The molecular structure of RUSTOPAK® consists of a highly polar sulfonate/carbonate head group (CaSuX) and an aromatic hydrocarbon structure. The strongly polar sulfonate head groups having a highly electronegative polar head (−SO3−) exhibit a higher affinity (charged) towards the metallic substrate (slightly positive charge) than water, achieving superb wetting and displacement of moisture.
Concurrently, a neutralization bond occurs between the mild sulfonic acids (RSO3H) in the formulation and the zinc carbonate (ZnCO3) layer present on galvanized surfaces producing a robust, integrated zinc sulfonate matrix upon application of the product. This neutralization bond, combined with the dense alkaline core of the overbased complex, permanently raises the local interfacial environment to an alkaline pH ≥ 10.1.
This sustained alkaline shift renders the environment thermodynamically hostile to corrosion, RUSTOPAK® effectively arrests zinc oxidation solving Differential Aeration Corrosion.
Key Innovation: The integration of an overbased crystalline calcium carbonate structure within a highly polar sulfonate matrix allows the coating to wet the metal substrate thoroughly, displace residual trace moisture, and chemically alter the interfacial environment to actively inhibit corrosion.
06
Crevice Corrosion
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A typical description of crevice corrosion refers to the attack of metal surfaces that are in contact with each other where stagnant water conditions can contribute to the corrosion in the crevice, for example around the edges of nuts and rivet heads. When dust, sand and other corrosive substances are deposited on surfaces, they create an environment where water will accumulate and corrode the metal part. It can happen between two metals or between a metal and a non-metal. This causes damage to the metallic part, which is initiated by the concentration gradient in chemicals. Oxygen causes an electrochemical concentration cell inside the crevice. This is a differential aeration cell where the oxygen in the crevice (the anode), and the oxygen content decreases, lowering the pH making the micro-environment more acidic.
For chlorides, the electrochemical concentration is higher on the inside of cervices, which worsens the corrosion. When a ferrous metal is present, the ferrous ions react with the chlorides to form ferric chloride, which attacks the steel and in particular stainless steel. This makes the concentration of both the oxygen and the pH remains lower in the crevice than the concentration in the water solution that forms on the metal. The propagation mechanism is similar to that of pitting corrosion.
There are factors that influence crevice corrosion. These include:
Type of crevice - either metal to metal or metal to non-metal
Geometry of the crevice - The size of the gap, its depth and the surface roughness
Composition of the metal - The structure of the alloy composition and can be Cr, Mo, or other metals
Environment - The pH, halide ions, temperature, oxygen, chloride levels and Relative Humidity (RH)
The resistance of a material to crevice corrosion can be ranked and evaluated by its critical crevice temperature (CCT), but this has to be in accordance with the ASTM Standard G48-03. CCT is the minimum temperature in °C that can produce a crevice attack, and is found to be lower than the critical pitting temperature (CPT).
How can crevice corrosion be prevented?
Replace riveted joints with welded butt joints.
Eliminate crevices in lap joints through continuous welding and soldering.
Drain existing solutions on surfaces and avoid creating stagnant conditions.
Use solid and non-absorbent gaskets.
Use higher alloys.
Exclude any further contact with moisture that causes differential aeration cells in crevices with RUSTOPAK® rendering treated crevices hydrophobic with a permanent interfacial alkaline environment of pH ≥ 10.1 that actively stops crevice corrosion.
07
Intergranular Corrosion
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This is a corrosion type that attacks the boundaries of the metal crystallites, as opposed to attacking the surface of the metal. Intergranular corrosion can also be referred to as intergranular attack under a condition known as grain boundary depletion.
Metals and alloys, like other elements, have micro-structures that can be described as grains. Metals can contain multiple grains, and these are separated by a grain boundary. Intergranular corrosion can be defined as an attack along the boundaries of several grains in the metal or near the grain boundary with the largest portion of the grain remaining unaffected.
The relation of corrosion to the grains can be explained in terms of element segregation. When an element adequate for the resistance of corrosion is lost, either from the boundary or the zone adjacent to it, it creates a condition where the spot becomes an anode with reference to the rest of the grain. Corrosion then proceeds along the affected grain boundary and may cause grains to dislodge due to the boundary deterioration.
Stainless steels and weld decay sensitization are the best examples of intergranular corrosion. Grain boundaries that are rich in chromium elements will precipitate chromium carbides (such as M23C6). This makes the boundaries very vulnerable to corrosion attacks in various electrolytes. This is caused by reheating the part that has been welded, especially in multi-pass welding.
In the process of intergranular corrosion, a knife-like attack, a form of intergranular corrosion, can occur when carbon reacts with niobium, titanium or the austenitic stainless steels. Carbides form in the areas close the welded part, making it difficult for them to diffuse. This condition can be corrected by reheating the part to enable the carbides to diffuse.
Aluminium-base alloys are mostly affected by this corrosion due to two main reasons. The first is when the phases anodic to aluminium are along the grain boundaries. The second is due to the depleted parts of copper which are adjacent to the boundaries. Other alloys that are prone to intergranular corrosion are those that have elongated and flattened grain micro-structures. These are the heavily worked on alloys or those that have been extruded.
Encapsulating areas with intergranular corrosion, RUSTOPAK® blocks out the environment arresting the cause during the engineered life cycle of the product.
08
Pitting Corrosion
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Pitting is a type of corrosion that occurs in materials that have protective films. It is an attack with localized holes on the metal's surface. The attack can penetrate the metal very rapidly, while some parts of the metal surface remain free from corrosion.
Pitting is vigorous when the solution on the metal surface contains chloride, hypochlorite or bromide ions. Other harmful solutions are those that contain fluorides and iodides, while sulfides (USA) and water are known to enhance the pitting process.
When metal is exposed, its available electrons are given up, and thus tiny pits begin to form on the metal surface. This then grows to become a rapid attack that results in massive damage of the metal. The oxidizing cation of iron, copper and mercury, among others, enables the formation of pitting even when there is no supply of oxygen in the metal surface. Stainless steel, chromium, passive iron, cobalt, aluminium, copper and associated alloys are all prone to pitting corrosion.
A tubercular morphology can be seen where pits develop. Pitting is not always local in nature, as even when intrinsic defects in the solution-metal interface, the potential nuclei remains intact. Their development and stabilization show a random nature, and galvanic coupling established in the zones of discontinuity where metal dissolution occurs, lead to the formation of small anodes.
Pitting corrosion can be controlled by:
Use of a more resistant material.
Ensuring that the fluids in contact with the material are either washed away or are injected at a high velocity.
Reducing the medium's aggressiveness.
Use of cathodic protection.
Avoiding stagnant zones.
Use of appropriate materials for service conditions.
Proper use of inhibitors or control of fluid chemistry.
Use of a coating sealant that will prevent pitting on metal surfaces.
The ability to maintain the protective film of the same material.
Encapsulating areas with pitting corrosion, RUSTOPAK® blocks out the environment arresting the cause during the engineered life cycle of the product.
09
Fretting Corrosion
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Fretting is gradual wear by means of rubbing or gnawing action between two surfaces. Fretting corrosion is a combined action of fretting as well as corrosion, which involves corrosion at points where two metal surfaces make contact by means of a rubbing action. Fretting corrosion is also known as chafing corrosion.
For fretting corrosion to occur, the following conditions need to be satisfied:
Interface must be under load.
Relative motion must occur and should be sufficient enough to produce deformation on the surface.
Fretting corrosion is common in:
Riveted joints/structures.
Bolted joints/flanges.
Problems generated by means of fretting corrosion are very expensive to fix. There is no standard test method to identify fretting corrosion. Mechanical design plays a more important role than material selection when facing this kind of corrosion. While it cannot be eliminated completely, it can be reduced by using inhibitive caulking compounds in the joints. The use of an “active” penetrant bases on calcium sulfonate in joints will inhibit corrosion.
Fretting corrosion can be prevented by:
Reducing relative movement between materials.
Using materials that are not susceptible to fretting corrosion.
Increasing the hardness of one or both materials.
Using contact lubricants.
Using seals to absorb vibrations.
Applying RUSTOPAK® which can accommodate the movement requiring consultation on the application specifics.
10
Stress Corrosion
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Stress corrosion refers to the degradation and/or rust formation of a given metal surface in an electrochemical fluid environment due to the metal being subjected to tensile forces in residual or direct form.
Stress corrosion erodes the microscopic granular composition of a metal surface, often causing the surface to crack and disintegrate due to significant tensile stresses.
Metal modification processes such as welding, cold or hot bending, machining, or grinding can create residual stresses in a metal, which accelerate stress corrosion. Certain metals such as stainless steel, carbon steel and copper alloys are more prone to stress corrosion in corresponding electrochemical environments.
Encapsulating areas with stress corrosion, RUSTOPAK® blocks out the environment arresting the cause during the engineered life cycle of the product.
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TECHNOLOGY
One-Coat Active Corrosion Mitigation
RUSTOPAK® High Ratio Calcium Sulfonate Alkyd (HRCSA) one coat active corrosion mitigation coating system is single-component polymer architecture that chemically alters the interfacial environment to actively inhibit corrosion. As an over-based sulfonate-carbonate complex formulated as a bridge maintenance overcoating system, the product is applied to zinc bearing steel (Hot Dip Galvanized), un-galvanised metal with tightly adherent corrosion and where grit blasting is still being specified. The HRCSA encapsulates tightly adherent weathered coatings, actively sealing off assets that are managed by Departments of Transport (DOT) throughout the US.
BOND
Polar chemistry supports metal wetting, moisture displacement and direct-to-metal adhesion.
SEAL
A high-film-build coating creates a hydrophobic barrier against moisture, oxygen and contaminants.
MODIFY
An alkaline reserve supports an interfacial environment less favourable to ongoing corrosion activity.
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CORROSION EXPLAINED
This Process Requires a Corrosion Cell
The thermodynamic instability of metals drives corrosion. Many metals occur naturally as stable, lower-energy compounds in ores. Extracting them requires energy, leaving the refined metal in a higher-energy state relative to those compounds. Under suitable environmental conditions, metals react to form more stable compounds. In atmospheric corrosion, this electrochemical process requires a corrosion cell. Moisture, oxygen, salts and differences in electrical potential can support corrosion-cell activity at joints, fasteners, crevices and weathered steel surfaces. Visible rust is often only the final sign of activity that began beneath or between connected surfaces.
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LEGAL & PRIVACY
WEBSITE TERMS & PRIVACY NOTICE
The following terms explain the use of this website and how RUSTOPAK (Pty) Ltd handles personal information submitted through RUSTOPAK®.
WEBSITE TERMS OF USE
1. ACCEPTANCE OF TERMS
By accessing or using rustopak.com, you agree to these Website Terms of Use. If you do not agree, please do not use this website.
2. WEBSITE INFORMATION
The technical information on this website is provided for general information only. It does not replace a project-specific assessment, product data sheet, application specification or written recommendation from RUSTOPAK®.
3. INTELLECTUAL PROPERTY
All website content, including text, graphics, logos, technical material and images, is the property of RUSTOPAK (Pty) Ltd, RUSTOPAK® or its authorised content providers, and may not be reproduced without written permission.
4. LIMITATION OF LIABILITY
To the fullest extent permitted by law, RUSTOPAK (Pty) Ltd shall not be liable for loss or damage arising from use of this website or reliance on its general information. Technical suitability must be confirmed for the relevant asset, environment and application.
5. GOVERNING LAW
These Website Terms of Use are governed by the laws of the Republic of South Africa.
PRIVACY & POPIA NOTICE
1. PERSONAL INFORMATION WE COLLECT
We may collect personal and business information you submit through enquiries, technical-information requests, data-upload forms and direct correspondence. This may include your name, contact details, company details, project information and supporting files.
2. HOW WE USE INFORMATION
We use this information to respond to enquiries, assess technical requirements, provide requested information, manage business communications and improve our services.
3. DISCLOSURE AND SECURITY
We do not sell or rent personal information. Access is limited to authorised personnel and service providers where necessary for the stated purpose, or where disclosure is required by law. We apply reasonable safeguards to protect information in our possession.
4. YOUR RIGHTS
You may request access to, correction of or deletion of your personal information where applicable. To make a request or raise a privacy concern, contact us at [email protected].
RUSTOPAK (Pty) Ltd Registration Number: 2017/525641/07 rustopak.com · [email protected] Last updated: 20 September 2026
Evidence & Resources
Bibliography
Research, technical guidance and industry references informing RUSTOPAK® corrosion mitigation practice and its application to targeted infrastructure maintenance.
Section 18.3.5 identifies high ratio calcium sulfonate within bridge zone preventive-maintenance systems, including spot treatment of corroded areas and zone overcoating.
Relevant section: 18.3.5, Example Preventive Maintenance Painting Systems
Peer-reviewed national research mapping atmospheric corrosivity across South Africa using ISO 9223:2012 categories and measured mild-steel corrosion rates.
Janse van Rensburg, D.T.; Cornish, L.A.; Van der Merwe, J. DOI: 10.17159/sajs.2019/4901
An Investigation into the Methodology to Develop an Insulator Pollution Severity Application Map for South Africa
A South African study examining salt deposition, atmospheric pollution and corrosion measurements along coastal-to-inland electrical infrastructure routes.
BS 5493:1977, Code of Practice for Protective Coating of Iron and Steel Structures Against Corrosion
Historic protective-coating guidance from the pre-ISO 12944 era, reflecting established principles of coating-system selection and maintenance planning.
BS 5493:1977. Historical reference; see BSI for current status.
The sources listed here provide technical and industry context. Their inclusion does not imply endorsement of RUSTOPAK® by the publishing organisation.
Technical Support
Frequently Asked Questions
Straightforward answers to common questions about HRCSA technology, surface preparation, application and suitable service environments.
What is HRCSA?
HRCSA means High Ratio Calcium Sulfonate Alkyd. RUSTOPAK® is a single-component, direct-to-metal coating system formulated to provide active corrosion mitigation through its protective film and alkaline interfacial environment.
Is RUSTOPAK® a primer or a topcoat?
RUSTOPAK® Top Coat is a one-coat direct-to-metal system formulated to substitute conventional primer, intermediate and topcoat configurations where the assessed substrate and project specification permit its use.
Is abrasive blasting always required?
No. HRCSA maintenance applications can substantially reduce the need for sweep or grit blasting. Loose corrosion, failed coating, contamination and other unsound material must still be removed using the preparation method appropriate to the substrate and project specification.
Can RUSTOPAK® be applied over an existing coating?
It may be applied over compatible, firmly adherent weathered coatings after inspection and suitable preparation. Existing coating condition, adhesion and compatibility must be assessed before application.
Is RUSTOPAK® suitable for C4 and C5 environments?
The system is positioned for demanding C4 and C5 atmospheric exposure conditions using ISO-aligned assessment principles. Final suitability depends on the substrate, local exposure, project specification, preparation and required film thickness.
Can it be used on solar mounting structures and transformers?
Yes, these are important RUSTOPAK® application areas. The system is intended for suitable zinc-bearing and steel infrastructure, including corrosion-prone interfaces, joints and structural components, subject to project assessment and specification.
Is RUSTOPAK® suitable for submerged service?
No. RUSTOPAK® is intended for atmospheric and appropriate non-submerged service conditions. It should not be specified for continuous immersion or submerged service.
What surface preparation is required?
The surface must be sound and suitably prepared. Loose corrosion, loose coating, dirt, grease, salts and other contaminants must be addressed. The final preparation procedure depends on the substrate, existing coating condition and approved project requirements.
What wet-film and dry-film thickness is required?
The standard project reference is 600 μm wet-film thickness, producing approximately 360 μm dry-film thickness. The approved project specification and quality-control requirements remain authoritative.
What is the difference between RUSTOPAK® Penetrant and Top Coat?
RUSTOPAK® Penetrant is a low-viscosity aerosol designed to wet and penetrate difficult joints, crevices and inaccessible areas. RUSTOPAK® Top Coat forms the main protective coating film. Where specified, the products are used together in a wet-on-wet application sequence.
What climatic conditions must be checked during application?
Project records must consider rain, wind, ambient and surface temperature, relative humidity and dew point. Surface temperature must remain at least 3°C above the dew point. Application must follow the approved technical and project requirements.
Where can technical documents and test reports be found?
Use the Evidence & Resources section for technical documents, testing and performance reports, specifications, industry references and bibliography sources.
Have a project-specific technical question that is not answered here?
Submit your completed quality records and supporting documents. Include the technician, company, site and structure details so we can identify your submission.
TECHNICAL TRAINING
Technician Training & Accreditation
Build the knowledge and practical skills to apply Rustopak® with care, consistency and accurate project records.
The programme prepares technicians to work with Rustopak® ISO 9001:2015 aligned Quality Management Instructions (QMI) across industrial coating projects.
HRCSA theoretical training · Course materials and inspection equipment
08Training sessions
5h 40mScheduled presentations & theory examination*
On-sitePractical demonstration & trainee practice
*Approximate total for sessions 1–7, excluding breaks. Practical duration depends on site requirements.
PURPOSE
Competence at every project phase
The objective is to deploy trained, authorised and accredited Rustopak® technicians with the knowledge to follow the QMI, carry out project tasks and maintain the required records.
WHO SHOULD ATTEND
Maintenance contractor teams
Maintenance contractors arrange theoretical and practical training for eligible technicians.
Able to read, speak and write in English.
Physically fit and able and permitted to work at heights.
CORE COMPETENCIES
What technicians will learn
01
Storage & handling
Follow product handling guidelines from receipt through to disposal.
02
Climatic conditions
Assess dew point, relative humidity and surface temperature.
03
Surface checks
Evaluate coating adhesion, surface cleanliness, surface temperature and chloride levels using the applicable inspection and testing requirements.
04
Application skills
Handle products and materials correctly, operate equipment safely and apply the specified wet film thickness (WFT).
05
Product calculations
Calculate product consumption throughout the application process.
06
Quality records
Maintain precise, comprehensive records for the manufacturer, Rustopak and asset owners, following the applicable TDS and QMI requirements.
YOUR TRAINING PATH
From understanding to application
Select a session to see its topics and hold points.
01Corrosion & the Rustopak coating system± 60 min+
Corrosion explained.
Rustopak High Ratio Calcium Sulfonate Coating Service.
02People, toolbox & sample application± 40 min+
Staff details and qualifications — Hold Point 01.
Toolbox — Hold Point 02.
Sample application — Hold Point 03.
03Climatic conditions± 35 min+
Climatic Conditions — Hold Point 04.
Assessing dew point, relative humidity and surface temperature forms part of the programme’s climatic competency requirements.
04Surface conditions± 60 min+
Surface Conditions — Hold Point 05.
Visual inspection of existing coating adhesion.
Visual standard for surface cleanliness of prepared surfaces (particles).
Test for chlorides.
Surface temperature measurement.
05Application & film thickness± 65 min+
Application — Hold Point 06.
Wet Film Thickness Gauge.
Dry Film Thickness: Non-destructive Test.
06Storage, handling & waste disposal± 35 min+
Storage & Handling — Hold Point 07.
Waste Disposal — Hold Point 07.
07Theory examination± 45 min+
Examination of theory by the trainer.
08On-site practicalSite dependent+
Site arrangements are coordinated before and after the practical, covering equipment, toolbox, product and the structure.
Practical demonstration by the trainer.
Trainee practical.
The duration is determined by site information.
ASSESSMENT & RECORDS
Demonstrate competence. Record successful completion.
The programme includes a theory examination and an on-site practical. Following successful course completion, accredited technician details are processed onto the Rustopak database.
Supporting instructions
Training works with the Rustopak ISO 9001:2015 aligned Technical Data Sheet and Quality Management Instructions.
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TESTING & ANALYSIS
Electrochemical Impedance Spectroscopy
Understanding the EIS measurement method and how its data is interpreted.
01
Measurement method
Electrochemical Impedance Spectroscopy (EIS) is a non-destructive, in-situ technique used to characterize corrosion by measuring the electrical impedance of a system across a wide frequency range, typically 100,000 to 0.01 Hz. The method applies a small alternating voltage and measures the resulting current to determine parameters such as polarization resistance, charge transfer resistance, and double-layer capacitance, which are used to calculate corrosion rates and analyze coating degradation.
02
Reading the data
Data is visualized using Nyquist or Bode plots and interpreted by fitting the spectra to Equivalent Electrical Circuits (EEC). These models separate different electrochemical processes, such as fast electron transfer at high frequencies and slow ion diffusion at low frequencies, allowing for the identification of mechanisms like pitting, passivation, and the effectiveness of protective coatings.
A FOCUSED TECHNICAL CONVERSATION
Meet with Rustopak
Arrange a private discussion about your project with Quentin. Include selected colleagues or technical allies so the right people can join the conversation.
Design preview · No booking, email or calendar invitation will be sent.
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Performance Evaluation of One-Coat Systems for New Steel Bridges
HRCSA performed well in accelerated laboratory and outdoor exposures, ranking second overall after the three-coat control. The report describes an alkaline coating that supports corrosion mitigation through its hydrophobic properties and strong ionic bonding with metal substrates, neutralising acidity and promoting passivity at the steel surface.
Laboratory method: similar to ASTM D5894-05, with an added freeze cycle.
Are you passionate about corrosion mitigation and the long-term preservation of industrial assets?
RUSTOPAK® would like to connect with technically minded professionals interested in contributing their knowledge, practical experience and commitment to this field.
We welcome interest from people with experience in one or more of the following:
Corrosion assessment and mitigation.
Industrial coatings and application.
Coating inspection, quality assurance and technical reporting.
Project management and asset maintenance.
We value people who ask thoughtful questions, communicate clearly, take pride in their work and are willing to keep learning. Practical problem-solving, sound technical judgement and attention to quality are central to the relationships we want to build.
If this speaks to you, tell us about your background, the projects you have worked on and where you believe you could contribute to the functions of the RUSTOPAK® Technical Support Team. Please include where you are based and the areas you can serve.
Start a conversation
Use our Technical Partner Interest form. Introduce yourself in the message field and add your professional profile link, if available.
You can also email a short introduction and your CV or professional profile to [email protected].
Email subject: Technical Partner Interest
This invitation is for professional collaboration. Opportunities and working arrangements will be discussed individually.
QUALITY MANAGEMENT
Uncompromising Quality, Traceable Excellence
ISO 9001:2015-Aligned Management from Supply Chain to On-Site Execution
Our Technical Support Team (TST) drives product manufacturing, material distribution and global supply chain logistics, while our Quality Management Team (QMT) drives quality workmanship standards and standardization of documentation on-site during seamless integration of data processing.
Guided by our controlled Technical Data Sheet (RSP-HRCSA-TC-TDS-26-01) and Quality Management Instruction (RSP-QMI-26-04), our teams maintain process simplicity and leadership responsibilities.
The RUSTOPAK® Service Guide provides a comprehensive framework covering site and structural assessments. It sets qualification standards for RUSTOPAK® Technicians (Applicators & Supervisors) and Quality Control Managers, outlining requirements for Contractor Applicator Accreditation. Rustopak (Pty) Ltd. ISO 9001:2015-aligned Technical Data Sheet (TDS) RSP-HRCSA-TC-TDS-26-01 functions in conjunction with the Rustopak (Pty) Ltd. ISO 9001:2015-aligned Quality Management Instruction RSP-QMI-26-04 for repeatable quality monitoring, data capturing, authorization and verification by the Rustopak (Pty) Ltd. Quality Management Team (QMT) for management controls.
Note: Logistics and site access are governed by environmental protection laws, occupational health and safety regulations, and restrictions on hazardous substances.
02
Site, Structure and Equipment Assessment
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Site, structure and equipment assessments are coordinated jointly by representatives from the Asset Owner, the Contractor and the Rustopak (Pty) Ltd. Quality Management Team (QMT). The Contractor and QMT must confirm site location, environmental conditions, site access, and site establishment in writing.
Click the photographs to enlarge
The Asset Owner, Contractor, and QMT jointly coordinate the structure and equipment assessment file. Per RSP-QMI-04 guidelines, the Contractor and QMT complete this file with Quality Control Certificates (QCCs) for each coating system based on the specific substrate, surface condition, preparation requirements, application procedures, and necessary tools. Additionally, both parties must confirm surface area measurements and application locations in writing. Any structural or equipment defects requiring repair or replacement fall outside the scope of the RUSTOPAK® assessment and remain the Asset Owner's responsibility.
SECTION
DESCRIPTION
RSP-QMI-26-04
RSP QCC
INTRODUCTION
1
STAFFING REPORT – Hold Point 01
RSP QMI-04-01
RSP QCC-04-01
2
STORAGE & HANDLING – Hold Point 02
RSP QMI-04-02
RSP QCC-04-02
3
CLIMATIC CONDITIONS – Hold Point 03
RSP QMI-04-03
RSP QCC-04-03
4
COATING ADHESION – Hold Point 04
RSP QMI-04-04
RSP QCC-04-04
5
SURFACE CLEANLINESS – Hold Point 05
RSP QMI-04-05
RSP QCC-04-05
6
SURFACE TEMPERATURE – Hold Point 06
RSP QMI-04-06
RSP QCC-04-06
7
SURFACE CHLORIDE – Hold Point 07
RSP QMI-04-07
RSP QCC-04-07
8
WET FILM THICKNESS – Hold Point 08
RSP QMI-04-08
RSP QCC-04-08
9
CALCULATIONS – Hold Point 09
RSP QMI-04-09
RSP QCC-04-09
10
WASTE MANAGEMENT – Hold Point 10
RSP QMI-04-10
RSP QCC-04-10
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03
Sample Application
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The RUSTOPAK® test sample application certificate is jointly coordinated by the Asset Owner, Contractor, and the QMT. It records the specific substrate, surface condition, preparation methods, application procedures, tools, equipment, and time allocated for a given area, all of which require signed approval from the Asset Owner’s representative or Project Engineer.
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The Contractor provides the site, structure, and equipment assessment file along with the test sample QCCs to the QMT for the Asset Owner's approval. All project planning and costing correspondence will be managed between the parties.
04
Logistics
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The Contractor in co-ordination with the Asset Owner must ensure that the correct storage facilities are available to receive the shipment on site.
Shipping container load capacities:
20 ft Light Container Load (LCL) single stack (8 x pallets) = 8 x 36 pails = 288 x 20 litre pails.
20 ft Full Container Load (FCL) double stack (16 x pallets) = 16 x 36 pails = 576 x 20 litre pails.
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05
RUSTOPAK® Training
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RUSTOPAK® Theoretical Training
To ensure consistent quality across industrial coating applications using RUSTOPAK® High Ratio Calcium Sulfonate Alkyd, Technicians (Applicators and Supervisors) and Quality Control Managers complete theoretical training on Quality Management Instruction RSP-QMI-26-04. This ISO 9001:2015-aligned instruction establishes standard procedures for quality monitoring, data capture, authorization and management verification for corrosion control. The curriculum includes:
SECTION
DESCRIPTION
RSP-QMI-26-04
RSP QCC
INTRODUCTION
1
STAFFING REPORT – Hold Point 01
RSP QMI-04-01
RSP QCC-04-01
2
STORAGE & HANDLING – Hold Point 02
RSP QMI-04-02
RSP QCC-04-02
3
CLIMATIC CONDITIONS – Hold Point 03
RSP QMI-04-03
RSP QCC-04-03
4
COATING ADHESION – Hold Point 04
RSP QMI-04-04
RSP QCC-04-04
5
SURFACE CLEANLINESS – Hold Point 05
RSP QMI-04-05
RSP QCC-04-05
6
SURFACE TEMPERATURE – Hold Point 06
RSP QMI-04-06
RSP QCC-04-06
7
SURFACE CHLORIDE – Hold Point 07
RSP QMI-04-07
RSP QCC-04-07
8
WET FILM THICKNESS – Hold Point 08
RSP QMI-04-08
RSP QCC-04-08
9
CALCULATIONS – Hold Point 09
RSP QMI-04-09
RSP QCC-04-09
10
WASTE MANAGEMENT – Hold Point 10
RSP QMI-04-10
RSP QCC-04-10
Click the photographs to enlarge
Theoretical training is facilitated through our Training section and should in-person theoretical training be coordinated by the QMT by requirement, the training venue must be facilitated by the Contractor and/or the Asset Owner.
Technicians (Applicators and Supervisors) and Quality Control Managers undergo hands-on training covering product storage and handling, site preparation, surface preparation and application procedures. To maintain consistent quality, the RUSTOPAK® Technical Data Sheet RSP-HRCSA-TC-TDS-26-01 operates alongside the Quality Management Instruction RSP-QMI-26-04 both aligned with ISO 9001:2015 standards to govern data logging, authorization, verification, and management oversight.
Click the photographs to enlarge
06
RUSTOPAK® High Ratio Calcium Sulfonate Alkyd Applications
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Site establishment by Contractors regulates the requirements on site. Technical Data Sheet (TDS) RSP-HRCSA-TC-TDS-26-01 and Quality Management Instruction RSP-QMI-26-04, appropriate storage, product, qualified Technicians (Applicators and Supervisors) and Quality Control Managers and all required equipment to be in place.
During the RUSTOPAK® application process, Rustopak (Pty) Ltd. ISO 9001:2015-aligned Technical Data Sheet (TDS) RSP-HRCSA-TC-TDS-26-01 functioning in conjunction with the Rustopak (Pty) Ltd. ISO 9001:2015 aligned Quality Management Instruction RSP-QMI-26-04 for repeatable quality monitoring, data capturing, authorization and verification for management controls is used and capturing is retained by the Quality Control Managers and distributed to the Asset Owner and loaded onto https://www.rustopak.com/#upload on pre-determined intervals confirmed in writing. Quality verification provided by the QMT.
Ultra-High Voltage (UHV) transmission tower - RUSTOPAK® joint sealant:
Click the photographs to enlargeClick the photographs to enlarge
Transformer rehabilitation completed after RUSTOPAK® Penetrant (Aerosol) and Top Coat application Click the photographs to enlarge
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