SigmaCover 280 is a universal epoxy anticorrosive primer, based upon pure epoxy technology, suitable for ballast tanks, decks, topside, superstructure, hull and cargo oil tanks. The primer is used in protective coating systems for steel and non-ferrous metals, curing at temperatures down to 5°C (41°F), and can be overcoated with most alkyd, chlorinated rubber, vinyl, epoxy and two-component polyurethane coatings.

Features & Benefits

• Used on the Second Wuhu Yangtze Bridge, Anhui Province, China
• Universal epoxy primer system suitable for Ballast Tanks, Decks, Topside, Superstructure, Hull and Cargo Oil Tanks
• General-purpose epoxy primer in protective coating systems for steel and non-ferrous metals
• Good adhesion to steel, galvanized steel, non-ferrous metals
• Good flow and wetting properties, water and corrosion resistance
• Cures at temperatures down to 5°C (41°F)
• Suitable for touching up of weld seams and damages of epoxy coatings during construction
• Excellent recoatability
• Can be overcoated with most alkyd, chlorinated rubber, vinyl, epoxy and two-component polyurethane coatings
• Suitable on wet blast cleaned substrates (damp or dry)
• Compatible with well-designed cathodic protection systems
• No induction time
• Can be applied by air spray, brush or roller
• See below for more information on surface preparation, application details and curing times

Product Data

Universal epoxy anticorrosive primer based upon pure epoxy technology.

Notes:

• Refer below for more details on spreading rate and film thickness, overcoating intervals and curing times

Surface Preparation

Recommended Substrate Conditions and Temperatures

Immersion exposure:

• Steel or steel with not approved zinc silicate shop primer
• Blast cleaned (dry or wet) to ISO-Sa2½, blasting profile 30 - 75 µm (1.2 – 3.0 mils)

• Steel with approved zinc silicate shop primer
• Weld seams and areas of damaged shop primer or breakdown should be blast cleaned to ISO-Sa2½, blasting profile 30 - 75 µm (1.2 – 3.0 mils) or power tool cleaned to SPSS-Pt3

• Coated steel
• Hydrojetted to VIS WJ2L (blasting profile 30 – 75 µm (1.2 – 3.0 mils))

IMO-MSC.215(82) requirements for water ballast tanks:

• Steel
• ISO 8501-3: 2006 grade P2, with all edges treated to a rounded radius of minimum 2 mm (0.0789 in) or subject to three pass grinding

• Steel or steel with not approved zinc silicate shop primer
• Blast cleaned to ISO -Sa2½, blasting profile 30 – 75 µm (1.2 – 3.0 mils)

• Steel with approved zinc silicate shop primer
• Weld seams and areas of shop primer damage or break down should be blast cleaned to Iso-Sa 2½ blasting profile 30 – 75 µm (1.2 – 3.0 mils):
1. For shop primer with IMO type approval: no additional requirements
2. For shop primer without IMO type approval: blast cleaned to ISO-Sa2 removing at least 70% of intact shop primer, blasting profile 30 – 75 µm (1.2 – 3.0 mils)
• Dust quantity rating "1 for dust size class "3", "4" or "5", lower dust size classes to be removed if visible on the surface to be coated without magnification (ISO 8502-3:1992)

Atmospheric exposure conditions:

• Steel blast cleaned to ISO-Sa2½, blasting profile 30 - 75 µm (1.2 – 3.0 mils) or according to ISO-St3
• Shop primed steel; pre-treated to SPSS-Pt3
• Galvanized steel must be sweep blasted or otherwise roughened
• Galvanized steel must be free from grease, salts and any contamination

Concrete / Masonry:

• Remove grease, oil and other penetrating contaminants according to ASTM D4258
• Abrade the surface per ASTM D4259 to remove all chalk and surface glaze or laitance. Achieve surface profile - ICRI CSP 3 to 5
• AMERCOAT 114 A may be used as a pit filler for certain applications. Check with PPG Technical Service for guidance on chemical resistance
• Maximum recommended moisture transmission rate is 3 lbs / 1,000 ft² / 24 hours by moisture transmission test (ASTM F1869, calcium chloride test or by ASTM D4263, plastic sheet test)
• Alternatively, ASTM D4944 (Calcium Carbide Gas method) can be used, moisture content should not exceed 4%

Substrate Temperature & Application Conditions

• Substrate temperature during application and curing should be above 5°C (41°F)
• Substrate temperature during application and curing should be at least 3°C (5°F) above dew point
• Relative humidity during application and curing should not exceed 85%

Application

Instructions for Use

Mixing ratio by volume: base to hardener 80:20 (4:1)

• The temperature of the mixed base and hardener should preferably be above 15°C (59°F), otherwise extra thinner may be required to obtain application viscosity
• Adding too much thinner results in reduced sag resistance and slower cure
• Thinner should be added after mixing the components

Induction Time

None.

Pot life

• 8 hours at 20°C (68°F)

Refer below for more information

Air Spray

Recommended thinner

• THINNER 91-92

Volume of thinner

• 0 - 10%, depending on required thickness and application conditions

Nozzle orifice

• 1.5 – 2.0 mm (approx. 0.060 – 0.079 in)

Nozzle pressure

0.3 - 0.4 MPa (approx. 3 - 4 bar; 44 - 58 p.s.i.)

Airless spray

Recommended thinner

• THINNER 91-92

Volume of thinner

• 0 - 10%, depending on required thickness and application conditions

Nozzle orifice

• Approx. 0.46 mm (0.018 in)

Nozzle pressure

• 15.0 MPa (approx. 150 bar; 2176 p.s.i.)

Brush/roller

Recommended thinner

• No extra thinner is necessary

Volume of thinner

• Up to 5% THINNER 91-92 can be added if desired

Cleaning Solvent

• THINNER 90-53

Spreading Rate and Film Thickness

Note:

• Maximum DFT when brushing: 50 µm (2.0 mils)

Overcoating interval for DFT up to 100 µm (4.0 mils)

• Surface should be dry and free from any contamination
• Glossy finishes require a corresponding undercoat

Note:

• Surface should be dry and free from any contamination

Curing time for DFT up to 200 µm (8.0 mils)

Notes:

• Adequate ventilation must be maintained during application and curing (please refer to information sheets 1433 and 1434)

Pot Life (at application viscosity)

Safety Precautions

• For paint and recommended thinners, see information sheets information sheet 1430, information sheet 1431 and the relevant Material Safety Data Sheets in the attachments section above
• This is a solvent-borne paint and care should be taken to avoid inhalation of spray mist or vapour, as well as contact between the wet paint and exposed skin or eyes

References

• Conversion Tables (information sheet 1410)
• Explanation to product data sheets (information sheet 1411)
• Safety Indicators (information sheet 1430)
• Safety in Confined Space and Health Safety, Explosion Hazard - Toxic Hazard (information sheet 1431)
• Safe Working in Confined Spaces (information sheet 1433)
• Directives for Ventilation Practice (information sheet 1434)
• Cleaning of Steel and Removal of Rust (information sheet 1490)
• Specification for Mineral Abrasives (information sheet 1491)
• Relative humidity - Substrate Temperature - Air Temperature (information sheet 1650)