The toughest universal high build epoxy primer for all areas down to ST2 - Engineered for faster production

Typical use

Suitable for structural steel and piping to be exposed to corrosive environments up to very high and immersed. Recommended for offshore environments, refineries, power plants, bridges, buildings, mining equipment and general structural steel. Specially suited in areas where high mechanical strength is required, such as splash or tidal zones. Compatible with cathodic protection systems.

Approvals and certificates

• NORSOK Standard M-501, Edition 6, Coating system no. 4 - Walkways, escape routes and lay down areas
• NORSOK Standard M-501, Edition 6, Coating system no. 7A - Carbon and stainless steel in the splash zone
• NORSOK Standard M-501, Edition 6, Coating system no. 7B - Submerged carbon and stainless steel ≤ 50°C

Additional certificates and approvals may be available on request - contact our Technical team on 0113 2455450 (option 2) or send a message to [email protected].

Quick Links - Click To Jump To Section:

• Features & Benefits
• Product Data
• Film Thickness Per Coat
• Film thickness measurement
• Surface Preparation
• Carbon Steel
• Abrasive blast cleaning
• Galvanised steel
• Aluminium
• Stainless steel
• Concrete
• Coated surfaces
• Application
• Drying and Curing Times
• Maximum over coating intervals

Features & Benefits

• Available in 350+ colours
• Two component polyamine cured epoxy coating
• Surface tolerant
• Can be applied on moist substrates
• Continues to cure when immersed in water
• High abrasion resistance
• Suitable for environments with very high corrosivity
• Splash zones
• Tidal zones
• Can be used as primer, mid coat, finish coat or as single coat system in atmospheric and immersed environments
• Excellent resistance to cathodic disbonding
• Suitable for properly prepared substrates:
• Carbon steel
• Galvanised steel
• Stainless steel
• Aluminium
• Concrete
• Recommended for:
• Offshore environments
• Refineries
• Power plants
• Bridges
• Buildings
• Mining equipment
• General structural steel
• Approved and certified: NORSOK Standard M-501, Edition 6, Coating system no's 4, 7A & 7B

Product Data

The provided data is typical for factory produced products, subject to slight variation depending on colour.

All data is valid for mixed paint.

Gloss description: According to Jotun Performance Coatings' definition.

Exposure to water or humidity soon after application may affect the coating surface and give a whitish appearance, especially on dark and strong colours. This will however not affect the protective properties.

Film Thickness Per Coat

Typical Recommended Specification Range

This product can be applied up to 50 % higher than maximum specified film thickness without loss of technical properties.

Film thickness measurement

Wet film thickness (WFT) measurement and calculation

To ensure correct film thickness, it is recommended to measure the wet film thickness continuously during application using a painter's wet film comb (ISO 2808 Method 1A). The measurements should be done as soon as possible after application.

Fast drying paints may give incorrect (too low) readings resulting in excessive dry film thickness. For multi layer physically drying (resoluble) coating systems the wet film thickness comb may give too high readings resulting in too low dry film thickness of the intermediate and top coats.

Use a wet-to-dry film calculation table (available on the Jotun Web site) to calculate the required wet film thickness per coat.

Dry film thickness (DFT) measurement

When the coating has cured to hard dry state the dry film thickness can be checked to SSPC PA 2 or equivalent standard using statistical sampling to verify the actual dry film thickness. Measurement and control of the WFT and DFT on welds is done by measuring the wet and dry film thickness adjacent to and no further than 15 mm from the weld.

Ventilation

Sufficient ventilation is very important to ensure proper drying/curing of the film.

Stripe coating

The stripe coat sequence can be either of the following:

1. Surface preparation, stripe coat, full coat.
2. Surface preparation, full coat, stripe coat. This sequence can be used when a large substrate area has been prepared and leaving the substrate exposed for a long time while doing stripe coating could lead to surface deterioration.

It is important to pay special attention to edges, openings, rear sides of stiffeners, scallops etc. and to apply a stripe coat to these areas where the spray fan may not reach or deposit an even film.

When applying a stripe coat to bare metal use only a stiff, round stripe coating brush to ensure surface wetting and filling of pits in the surface.

Stripe coating shall be of a different colour to the main primer coat and the topcoat colour and should be applied in an even film thickness, avoiding excessive brush marks in order to avoid entrapped air. Care should be taken to avoid excessive film thickness. Pay additional attention to pot life during application of stripe coats.

Jotun recommends a minimum of one stripe coat. However, in extremely aggressive exposure conditions there may be good reason to specify two stripe coats.

Coating loss

The consumption of paint should be controlled carefully, with thorough planning and a practical approach to reducing loss. Application of liquid coatings will result in some material loss. Understanding the ways that coating can be lost during the application process, and making appropriate changes, can help reducing material loss.

Surface Preparation

To secure lasting adhesion to the subsequent product all surfaces shall be clean, dry and free from any contamination.

Surface Preparation Summary Table

The required quality of surface preparation can vary depending on the area of use, expected durability and if applicable, project specification.

When preparing new surfaces, maintaining already coated surfaces or aged coatings it is necessary to remove all contamination that can interfere with coating adhesion, and prepare a sound substrate for the subsequent product.

Inspect the surface for hydrocarbon and other contamination and if present, remove with an alkaline detergent.

Agitate the surface to activate the cleaner and before it dries, wash the treated area using fresh water.

Paint solvents (thinners) shall not be used for general degreasing or preparation of the surface for painting due to the risk of spreading dissolved hydrocarbon contamination. Paint thinners can be used to treat small localized areas of contamination such as marks from marker pens. Use clean, white cotton cloths that are turned and replaced often. Do not bundle used solvent saturated cloths. Place used cloths into water.

When the surface is an existing coating, verify with technical data sheet and application guide of the involved products, both over coatability and the given maximum over coating interval.

Carbon steel

Initial rust grade

The steel shall preferably be Rust Grade A or B (ISO 8501-1). It is technically possible to apply the coating to rust grades C and D, but it is practically challenging to ensure specified film thickness on such a rough surface, hence risk of reduced lifetime of the coating system. When steel of Rust Grade C or D is coated, the frequency of inspection and testing should be increased.

Metal finishing

For areas in corrosivity category C1 to C4 (ISO 12944-2) all irregularities, burrs, slivers, slag and spatter on welds, sharp edges and corners shall conform to minimum grade P2 (ISO 8501-3) Table 1, or as specified. For areas in corrosivity category C5, Im1-3 the requirement are for the steel to conform to grade P2 (ISO 8501-3) Table 1. All edges shall have a rounded radius of minimum 2 mm subjected to three pass grinding or equally effective method. One may use a mechanical grinder fitted with a suitable abrasive disc. All sharp irregularities, burrs, slivers, slag and spatter on welds, whether apparent before or after blast cleaning, shall be removed before coating application. It is recommended that welding smoke should be removed by low-pressure Water Cleaning LP WC method (ISO 8501-4) Wa 1 using fresh water. Welding smoke residues are water soluble and could cause blistering if not removed by washing before blasting.

Defective welds shall be replaced and treated to an acceptable finish before painting. Temporary welds and brackets shall be ground to a flat finish after removal from the parent metal.

Surface preparation and coating should normally be commenced only after all metal finishing and degreasing of a specific area is complete. It is important that as much hot work as possible is completed before coating commences.

Pitting repair

Pittings in steel can be difficult to cover fully with most coatings. In some areas it is practically feasible to use filler to fill pittings. This should then be done either after the initial surface preparation or after application of first coat.

Abrasive blast cleaning

Application of protective coating shall commence before degradation of the required surface standard occurs.

Cleanliness

After pre-treatment is complete, the surface shall be dry abrasive blast cleaned to Sa 2½ (ISO 8501-1) using abrasive media suitable to achieve a sharp and angular surface profile.

Surface profile

Recommended surface profile 75-150 μm, grade Medium to Coarser than coarse G (ISO 8503-2). Measure the achieved profile with surface replication tape (Testex) to ISO 8503-5 or by a surface roughness stylus instrument (ISO 8503-4).

Abrasive media quality

The selected abrasive must be compatible with both the surface to be blast cleaned and the specified coating system. The abrasive shall meet specifications as per relevant parts of ISO 11124 (Specification for metallic blast-cleaning abrasives), or ISO 11126 (Specification for non-metallic blast-cleaning abrasives). It should be sampled and tested as per relevant parts of ISO 11125 (metallic abrasives) or ISO 11127 (non-metallic abrasives). Dry storage of abrasive and shelter for blasting pots is necessary to prevent equipment becoming clogged with damp abrasive.

All abrasive blast media used should be new and not recirculated, with the exception of steel grit. If this is utilized the circulation process must include a cleaning process.

Compressed air quality

The supply of clean air to blasting pots must be secured to avoid contamination of abrasive and thereby of blast cleaned surfaces. Compressors must be fitted with sufficient traps for oil and water. It is also recommended to fit two water separators at the blasting machine to ensure a supply of moisture-free air to the abrasive chamber.

Dust contamination

At the completion of abrasive blasting the prepared surface shall be cleaned to remove residues of corrosion products and abrasive media, and inspected for surface particulate contamination. Maximum contamination level is rating 1 (ISO 8502-3) as per Figure 1. Dust size no greater than class 2.

Galvanised steel

Abrasive blast cleaning

The galvanised finish shall be smooth as is consistent for a protective coating and shall have no sharp fins, sharp edges, dross or zinc ash on the surface. If present, remove by mechanical cleaning methods.

After removal of excess zinc and surface defects the area to be coated shall be degreased to ISO 12944-4, Part 6.2.4 Alkaline Cleaning. The galvanised surface shall be sweep blast-cleaned with the nozzle angle at 45-60° from perpendicular at reduced nozzle pressure to create a sharp and angular surface profile using approved non- metallic abrasive media. As a guide, a surface profile 25-55 µm, grade Fine G; Ry5 (ISO 8503-2) should be achieved.

Hand and Power Tool Cleaning

After removal of excess zinc and surface defects the area to be coated shall be degreased with an alkaline detergent, washed by Low-Pressure Water Cleaning (LPWC) to a grade corresponding to the description of Wa 1 (ISO 8501-4) or higher standard and the surface abraded using mechanical or hand sanding methods using non- metallic abrasives or bonded fibre abrasive pads to remove all polish and to impart a scratch pattern to the surface. Do not use high speed rotational sanders.

Water jetting

Inspect the surface for process residues, hydrocarbon contamination and zinc corrosion by-products. If present, remove with an alkaline detergent. Agitate the surface to activate the detergent and before it dries, wash the treated area by Low-Pressure Water Cleaning (LPWC) to a grade corresponding to the description of Wa 1 (ISO 8501-4) or higher standard using fresh water.

Optimum performance is achieved with preparation grade Wa 2½. Minimum preparation grade is Wa 1.

Aluminium

Abrasive blast cleaning

After pre-treatment of welds, sharp edges, removal of weld spatter and other surface contamination the surface shall be degreased using an alkaline detergent which is agitated with non-metallic brushes followed by rinsing using clean fresh water. The surface shall then be dry abrasive blast cleaned with an approved non-metallic abrasive media to create a sharp and angular surface profile. As a guide, a surface profile between 25-55 μm, grade Fine to Medium G; Ry5 (ISO 8503-2) should be achieved.

Hand and Power Tool Cleaning

After pre-treatment of welds, sharp edges, removal of weld spatter and other surface contamination the surface shall be degreased using an alkaline detergent which is agitated with non-metallic brushes and then fresh water rinsed. The cleaned surface shall be then hand or machine abraded with non-metallic abrasives or bonded fibre machine or hand abrasive pads to remove all surface polish and to impart a scratch pattern to the surface. Do not use high speed rotational sanders.

Water jetting

Surfaces not contaminated with hydrocarbon deposits shall be cleaned by Low-pressure Water Cleaning (LPWC) to a grade corresponding to the description of Wa 1 (ISO 8501-4) or higher standard using fresh water to remove all dusts, chloride and non-visible contamination.

Optimum performance is achieved with preparation to a grade corresponding to the description of Wa 2½. Minimum preparation grade is Wa 1.

Stainless steel

Abrasive blast cleaning

The surface to be coated shall be dry abrasive blast cleaned as required for the specified surface profile using approved non-metallic abrasive media which is suitable to achieve a sharp and angular surface profile. As a guide, a surface profile corresponding to 25-55 µm, grade Fine G; Ry5 (ISO 8503-2) should be achieved.

Examples of recommended abrasives are:

• Ferrite free almandite garnet grade 30/60 and 80 grade (US Mesh size)
• Aluminium oxide grade G24

Chlorinated or chlorine containing solvents or detergents must not be used on stainless steel.

Concrete

Blast cleaning

Dry abrasive blast cleaning to SSPC-SP 13/NACE No. 6.

Where the concrete has become contaminated with oils, grease, or fuels, alkaline detergent may be used to remove the contaminants. It is important to only clean an area that can be fully washed down after degreasing before the cleaner can dry on the surface. Where the contamination has penetrated deep in to the substrate it may be necessary to use Flame/ Thermal cleaning.

All prepared surfaces should then have all “blow holes” and other surface defects filled with suitable filler that is compatible with the primer and finish coat system to ensure that the coating can be applied over a smooth and regular substrate.

Diamond disc grinding

Diamond grind the surface to remove all laitance and expose the aggregates.

Coated surfaces

Shop primers

Shop primers are accepted as temporary protection of steel plates and profiles. However the shop primer should be completely removed through blast cleaning to minimum Sa 2½ (ISO 8501-1) using abrasive media suitable to achieve a sharp and angular surface profile 50-85 µm, grade Medium G; Ry5 (ISO 8503- 2).

Application

Acceptable environmental conditions - before and during application

Before application, test the atmospheric conditions in the vicinity of the substrate for the dew formation according to ISO 8502-4.

The following restrictions must be observed:

• Do not apply the coating if the weather is clearly deteriorating or unfavourable for application or curing
• Do not apply the coating in high wind conditions

Can be applied on moist substrates.*

* Moist: Blast cleaned substrate with apparent surface profile, with no accumulated water.

Application methods

The product can be applied by:

• Spray: Use airless spray.
• Brush: Recommended for stripe coating and small areas, care must be taken to achieve the specified dry film thickness.
• Roller: May be used for small areas but is not recommended for first primer coat. However, when using roller application care must be taken to apply sufficient material in order to achieve the specified dry film thickness.

Product mixing ratio (by volume)

• Marathon 550 Comp A - 4 part(s)
• Marathon 550 Comp B - 1 part(s)

Thinner/Cleaning solvent

• Thinner: Jotun Thinner No. 17

Guiding data for airless spray

• Nozzle tip (inch/1000): 21-27
• Pressure at nozzle (minimum): 170 bar / 2500 psi
• Pump ratio (minimum): 42:1
• Nozzle output (litres/minute): 2.0-3.2

Several factors influence, and need to be observed to maintain the recommended pressure at the nozzle. Among factors causing pressure drop are:

• Extended hoses or hose bundles
• Extended hose whip-end line
• Small internal diameter hoses
• High paint viscosity
• Large spray nozzle size
• Inadequate air capacity from compressor
• Incorrect or clogged filters

If the paint temperature from Spray gun reaches 50-55°C, a good rule is to stop spraying and start cleaning all the spray equipment to prevent breakdown.

Drying and Curing Times

Drying and curing times are determined under controlled temperatures and relative humidity below 85 %, and at average of the DFT range for the product.

Excess DFT and/or thinning will prolong drying and curing.

If the product is applied during the tidal zone on piles and jetties, it can be immersed after 1 hour. Early immersion will lead to a whitening of colours, most visible on darker colours. The corrosion performance is however not affected.

Surface (touch) dry: The state of drying when slight pressure with a finger does not leave an imprint or reveal tackiness.

Walk-on-dry: Minimum time before the coating can tolerate normal foot traffic without permanent marks, imprints or other physical damage.

Dry to over coat, minimum: The recommended shortest time before the next coat can be applied.

Dried/cured for service: Minimum time before the coating can be permanently exposed to the intended environment/medium.

Maximum over coating intervals

Maximum time before thorough surface preparation is required. The surface must be clean and dry and suitable for over coating. Inspect the surface for chalking and other contamination and if present, remove with an alkaline detergent. Agitate the surface to activate the cleaner and before it dries, wash the treated area by low- pressure water cleaning using fresh water.

If maximum over coating interval is exceeded the surface should in addition be carefully roughened to ensure good inter coat adhesion.

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