CORROSION PROTECTION OF STEEL STRUCTURES

PAINT SYSTEMS GUIDE IN ACCORDANCE WITH ISO 12944-5:2007 Issue date: June 2013 CORROSION PROTECTION OF STEEL STRUCTURES 1. Introduction Part 5 of ISO...
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PAINT SYSTEMS GUIDE IN ACCORDANCE WITH ISO 12944-5:2007 Issue date: June 2013

CORROSION PROTECTION OF STEEL STRUCTURES

1. Introduction Part 5 of ISO 12944 describes the different types of paint, most commonly used systems for corrosion protection of steel structures, recommended thicknesses and number of coats. This guide was created based on the recommendations of this standard and aims to assist in the selection of the most appropriate system for different environments (see part 2 of ISO 12944), the different grades of surface preparation (see part 4 of ISO 12944) and the degree of durability required (see part1 of ISO 12944).

2. Classification of environments according to different categories of corrosivity Environments are classified according to their grade of environmental corrosivity, both for structures exposed to atmospheric corrosivity and those which are buried or immersed. Table 1 gives some examples of environments for each type of corrosivity category and table 2 the corrosive agents which may affect a steel structure which is immersed or buried in the ground. Table 1: Categories of atmospheric corrosivity and examples of typical environments. Category of corrosivity C1 Very low C2 Low

Exterior

Interior

-

C4 High C5-I Very high (industrial)

Atmospheres with low levels of contamination. Rural areas. Urban and industrial atmospheres, with moderate SO2 contamination. Coastal areas with low salinity. Industrial areas and coastal areas with moderate salinity. Industrial areas with high humidity and with an aggressive atmosphere.

C5-M Very high (marine)

Coastal and marine areas with high salinity.

C3 Medium

Buildings with heating and clean atmospheres. Unheated buildings with possible condensation.

Manufacturing plants with high humidity and some contamination. Chemical industries, swimming pools. Buildings or areas with almost permanent condensation and high levels of contamination. Buildings or areas with permanent condensation and high levels of contamination.

All Portuguese territory is classified according to these categories of corrosivity in the “National Map of Atmospheric Corrosion”.

It is advisable to check on a regular basis the status of this guide. The systems recommended were based on commercially available products which CIN can withdraw without notice. This guide is generic and must be viewed as one possible example among many CIN Protective Coatings solutions. Consult CIN directly for a specification for a particular project.

CIN-CORPORAÇÃO INDUSTRIAL DO NORTE, SA Avenida Dom Mendo, nº831(antes E.N. 13) - Apartado 1008 4471-909 MAIA PORTUGAL Telef. 22 940 50 00 · Fax: 22 948 56 61 www.cinprotective.com· email: customerservice.pt

BARNICES VALENTINE, S.A.U. C/ Riera Seca, 1 – Pol. Ind. Can Milans 08110 – Montcada i Reixac (Barcelona) Tel. 34 93 565 66 00 · Fax: 34 93 575 33 60 www.cinprotective.com· [email protected]

CELLIOSE COATINGS Chemin de la Verriere - BP 58, 69492 Pierre Bénite Cedex · France Tél: +33 (0) 472 39 77 77 · Fax: +33 (0) 472 39 77 70 www.celiose.com Pág. 1/5

PAINT SYSTEMS GUIDE IN ACCORDANCE WITH ISO 12944-5:2007 Issue date: June 2013

Table 2: Category for immersion in water and the ground Category of corrosivity

Environment

Im 1

Fresh water

Im 2

Brackish or sea water

Im 3

Ground

Example of environment and structures River installations, hydroelectric plants. Harbour areas with structures such as floodgates, dykes, breakwaters, offshore platforms Buried tanks, pipes and girders.

3. Durability range The durability or years of useful life is defined as being the desired length of time before the first maintenance painting. The durability range is not a guarantee time. Low (L): 2 to 5 years Medium (M): 5 to 15 years High (H): > 15 years.

4. Surface preparation Prior to commencing blasting all visible traces of oil, grease, salts and other contaminants must be removed, so that they neither remain encrusted on the steel nor contaminate the abrasive. The correct approach must be adopted for each situation, for example:  To remove oil, grease or water soluble salts, jet wash with water (and detergent if necessary), steam clean, or use emulsions or organic solvents. Whenever detergent is used rinse with clean water.  Where there is weld spatter, insoluble salts, cement or other contaminants, use mechanical/manual methods ( for example brushing, rasping etc) Edges, corners and welded seams must be smoothed (minimum diameter 2mm), to facilitate the coating process. Following this, dry blast-clean to grade Sa 2½, in accordance with ISO Standard 8501-1. The choice of grit must be made to ensure a roughness profile between 25µm e 50µm, using Testex Tape or equivalent or by using comparators (G,S) in accordance with ISO 8503. Defects in the steel revealed after blasting (delamination, etc) must be repaired in the appropriate manner. If these treatments reduce the roughness then the blasting must be repeated. After blasting a final cleaning must be carried out using a powerful vacuum cleaner, leaving the surface dust free and suitable to accept the coating. The work will be complete when an adhesive tape applied to the surface shows no traces of dust.

It is advisable to check on a regular basis the status of this guide. The systems recommended were based on commercially available products which CIN can withdraw without notice. This guide is generic and must be viewed as one possible example among many CIN Protective Coatings solutions. Consult CIN directly for a specification for a particular project.

CIN-CORPORAÇÃO INDUSTRIAL DO NORTE, SA Avenida Dom Mendo, nº831(antes E.N. 13) - Apartado 1008 4471-909 MAIA PORTUGAL Telef. 22 940 50 00 · Fax: 22 948 56 61 www.cinprotective.com· email: customerservice.pt

BARNICES VALENTINE, S.A.U. C/ Riera Seca, 1 – Pol. Ind. Can Milans 08110 – Montcada i Reixac (Barcelona) Tel. 34 93 565 66 00 · Fax: 34 93 575 33 60 www.cinprotective.com· [email protected]

CELLIOSE COATINGS Chemin de la Verriere - BP 58, 69492 Pierre Bénite Cedex · France Tél: +33 (0) 472 39 77 77 · Fax: +33 (0) 472 39 77 70 www.celiose.com Pág. 2/5

PAINT SYSTEMS GUIDE IN ACCORDANCE WITH ISO 12944-5:2007 Issue date: June 2013

In the time that elapses between cleaning and the application of the coating, the preparation grades must not alter. Thus for example the maximum time between blasting and applying the paint should be between 4 and 6 hours depending on the ambient conditions. If the surface rusts before painting, the blasting process must be repeated to acquire the required degree of cleanliness.

Paint systems Below we detail some paint systems which comply with ISO 12944 as regards the type of product, thicknesses and number of coats to apply. Alternative systems exist, including with products not covered by the Standard. For more information consult Customer Service. All the systems presented here are for an estimated durability in excess of 15 years.

Category of corrosivity C2 Type of paint

System

Zinc phosphate epoxy Micaceous iron acrylic

1 × C-Pox Primer ZP200 HP 1 × C-Cryl S450 Mio Total film thickness 1 × C-Pox ST180 AL 1 × C-Thane S258 Total film thickness

Aluminium tolerant epoxy Polyurethane

Total dry film thickness (microns) 80 m 80m 160 m 110 m 50 m 160 m

Category of corrosivity C3 Type of paint

System

Zinc phosphate epoxy High thickness polyurethane

1 × C-Pox Primer ZP200 HP 1 × C-Thane S700 HB Total film thickness 1 × C-Pox ST180 AL 1 × C-Pox S100 1 × C-Thane S258 Total film thickness 1 × C-Pox ST160 MP Total film thickness

Aluminium tolerant epoxy Epoxy intermediate Polyurethane Surface tolerant epoxy

Total dry film thickness (microns) 100 m 100m 200 m 80 m 80 m 40 m 200 m 165 m 165 m

Note: taking into account that the thicknesses given for the last system shown above are less than those recommended in ISO 12944-5, we have test certificates in accordance with ISO 12944-6 (performance tests) which confirm that this system is valid for this category of corrosivity and durability of > 15 years.

It is advisable to check on a regular basis the status of this guide. The systems recommended were based on commercially available products which CIN can withdraw without notice. This guide is generic and must be viewed as one possible example among many CIN Protective Coatings solutions. Consult CIN directly for a specification for a particular project.

CIN-CORPORAÇÃO INDUSTRIAL DO NORTE, SA Avenida Dom Mendo, nº831(antes E.N. 13) - Apartado 1008 4471-909 MAIA PORTUGAL Telef. 22 940 50 00 · Fax: 22 948 56 61 www.cinprotective.com· email: customerservice.pt

BARNICES VALENTINE, S.A.U. C/ Riera Seca, 1 – Pol. Ind. Can Milans 08110 – Montcada i Reixac (Barcelona) Tel. 34 93 565 66 00 · Fax: 34 93 575 33 60 www.cinprotective.com· [email protected]

CELLIOSE COATINGS Chemin de la Verriere - BP 58, 69492 Pierre Bénite Cedex · France Tél: +33 (0) 472 39 77 77 · Fax: +33 (0) 472 39 77 70 www.celiose.com Pág. 3/5

PAINT SYSTEMS GUIDE IN ACCORDANCE WITH ISO 12944-5:2007 Issue date: June 2013

Category of corrosivity C4 Type of paint

System

Zinc ethyl silicate primer Epoxy intermediate Polyurethane

1 × C-Pox Primer IZS920 1 × C-Pox S130 FD 1 × C-Thane RPS HS Total film thickness 1 × C-Pox Primer ZN650 1 × C-Pox ST160 MP Total film thickness

Zinc-rich primer Surface tolerant epoxy

Total dry film thickness (microns) 75 m 125 m 50 m 250 m 50 m 100 m 150 m

Note: taking into account that the thicknesses given for the last system shown above are less than those recommended in ISO 12944-5, we have test certificates in accordance with ISO 12944-6 (performance tests) which confirm that this system is valid for this category of corrosivity and durability of > 15 years. We also have a test certificate for the first system.

Category of corrosivity C5M Type of paint

System

Zinc-rich primer Epoxy intermediate Polyurethane

1 × C-Pox Primer ZN800 1 × C-Pox S990 Mio FD 2 × C-Thane RPS HS Total film thickness

Total dry film thickness (microns) 75 m 85 m 80 m 240 m

Note: taking into account that the thicknesses shown above are less than those recommended in ISO 12944-5, we have test certificates in accordance with ISO 12944-6 (performance tests) which confirm that this system is valid for this category of corrosivity and durability of > 15 years.

Category of corrosivity C5M (cont.) Type of paint

System

Zinc phosphate epoxy primer Micaceous iron epoxy intermediate Polyurethane

1 × C-Pox Primer ZP200 HB 1 × C-Pox S990 Mio FD

Zinc epoxy primer High film thickness flexible polyurethane

Total dry film thickness (microns) 100 m 140 m

2 × C-Thane RPS HS Total film thickness 1 × C-Pox Primer ZP650 1 × C-Thane S690 HB-F

80 m 320 m 75 m 125 m

Total film thickness

200 m

Note: taking into account that the thicknesses given for the last system shown above are less than those recommended in ISO 12944-5, we have test certificates in accordance with ISO 12944-6 (performance tests) which confirm that this system is valid for this category of corrosivity and durability of > 15 years. We also have a test certificate for the first system.

It is advisable to check on a regular basis the status of this guide. The systems recommended were based on commercially available products which CIN can withdraw without notice. This guide is generic and must be viewed as one possible example among many CIN Protective Coatings solutions. Consult CIN directly for a specification for a particular project.

CIN-CORPORAÇÃO INDUSTRIAL DO NORTE, SA Avenida Dom Mendo, nº831(antes E.N. 13) - Apartado 1008 4471-909 MAIA PORTUGAL Telef. 22 940 50 00 · Fax: 22 948 56 61 www.cinprotective.com· email: customerservice.pt

BARNICES VALENTINE, S.A.U. C/ Riera Seca, 1 – Pol. Ind. Can Milans 08110 – Montcada i Reixac (Barcelona) Tel. 34 93 565 66 00 · Fax: 34 93 575 33 60 www.cinprotective.com· [email protected]

CELLIOSE COATINGS Chemin de la Verriere - BP 58, 69492 Pierre Bénite Cedex · France Tél: +33 (0) 472 39 77 77 · Fax: +33 (0) 472 39 77 70 www.celiose.com Pág. 4/5

PAINT SYSTEMS GUIDE IN ACCORDANCE WITH ISO 12944-5:2007 Issue date: June 2013

Category of corrosivity Im1, Im2 e Im3 Type of paint

System

Zinc-rich epoxy primer Surface tolerant epoxy

1 × C-Pox Primer ZN905 2 × C-Pox ST165 MP-WN Total film thickness 2 × C-Pox CT940

Total dry film thickness (microns) 60 m 400 m 460 m 400 m

Total film thickness

400 m

Coal tar epoxy

CIN has many other systems for corrosion protection of metal structures. For more information contact CIN Customer Service.

It is advisable to check on a regular basis the status of this guide. The systems recommended were based on commercially available products which CIN can withdraw without notice. This guide is generic and must be viewed as one possible example among many CIN Protective Coatings solutions. Consult CIN directly for a specification for a particular project.

CIN-CORPORAÇÃO INDUSTRIAL DO NORTE, SA Avenida Dom Mendo, nº831(antes E.N. 13) - Apartado 1008 4471-909 MAIA PORTUGAL Telef. 22 940 50 00 · Fax: 22 948 56 61 www.cinprotective.com· email: customerservice.pt

BARNICES VALENTINE, S.A.U. C/ Riera Seca, 1 – Pol. Ind. Can Milans 08110 – Montcada i Reixac (Barcelona) Tel. 34 93 565 66 00 · Fax: 34 93 575 33 60 www.cinprotective.com· [email protected]

CELLIOSE COATINGS Chemin de la Verriere - BP 58, 69492 Pierre Bénite Cedex · France Tél: +33 (0) 472 39 77 77 · Fax: +33 (0) 472 39 77 70 www.celiose.com Pág. 5/5

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