SPECIFICATION FOR PAINTING ON GALVANIZED SURFACES BY WET/ELECTROSTATIC POWDER PAINTING

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1 CHIEF CHEMIST DEPT. PAGE No. 1 SPECIFICATION FOR PAINTING ON GALVANIZED SURFACES BY WET/ELECTROSTATIC POWDER PAINTING 1. SCOPE This specification covers the requirements for painting of steel surfaces hot dipped or electrolytically galvanized. Galvanized steel shall be protected by paint (duplex system) except for threaded items such as nuts and bolts which will be chromated according to the instructions of the laboratory of materials. Painting on galvanized surfaces may be problematic and a test patch is recommended in order to assure a proper adhesion of the primer on the prepared surface. 2. SURFACE PREPARATION 2.1 On hot dip Galvanized items Solvent cleaning Cleaning all surfaces from dirt, dust, oil, grease using a suitable solvent to SSPC-PS Approved Chemitaas products: Ardox 6-551, BC-70 or similar products of other manufacturers.

2 CHIEF CHEMIST DEPT. PAGE No Surface treatment By one of the following methods: A. Brush-off blast cleaning According to SSPC-SP-7 specification. Will be performed only by authorized workers. Authorization shall be granted after ability to perform roughening of the zinc coating and remove no more than 10 microns of the zinc layer. The zinc layer thickness shall be examined before and after blasting. B. Chemical treatment Submerging the item in a phosphating bath type ZINC- PHOSPHATE conforming to BS standard. 2.2 On electrolytically galvanized items Solvent cleaning According to par Surface treatment By one of the following methods: A. Mechanical The surface shall be roughened to a degree suitable for the specified paint system. Approved surface cleaning media are listed in par B. Chemical treatment according to par B.

3 CHIEF CHEMIST DEPT. PAGE No PAINTING ENVIRONMENT SUBSTRATE PAINTING SYSTEM THICKNESS MICRON REMARKS 3.1 Internal location or external in a dry environment Hot dip galvanizing zinc layer thickness over 80 micron Liquid paints Epoxy polyamide modified special for galvanizes surfaces / two component aliphatic polyurethane Total Electrostatic power painting with pure polyester See par. 4.1 for manufactures and products see par. 6.1 and 6.2 remarks 60 See par. 4.2 for manufacturers and products. See par. 5 technical requirements Electrolyticaly galvanizing micron zinc layer thickness Liquid paints Epoxy polyamide modified special for galvanized surfaces 70 See par. 4.1 for manufactures and products Two component aliphatic polyurethane. Total See par. 6.1, 6.2 Remarks. ` Electrostatic painting with pure polyester 100 Total 100 See par. 4.2 for manufactures and products. See par. 5 technical requirements.

4 CHIEF CHEMIST DEPT. PAGE No. 4 ENVIRONMENT SUBSTRATE PAINTING SYSTEM THICKNESS MICRON REMARKS 3.2 External location marine or industrial fume environment Hot dip galvanizing zinc layer thickness over 80 micron Liquid paint epoxy polyamide modified special for galvanized surfaces 70 See par. 4.1 for manufactures and products. Two component Aliphatic Polyurethane 50 See par. 6.1 and 6.2 Remarks Total 120 External location marine or industrial fume environment Electrolitically galvanizing micron zinc layer thickness Electrostatic painting with pure polyester Epoxy polyamide modified special for galvanized surfaces. Two component aliphatic polyurethane 80 See par. 4.2 for manufacturer. See par. 5 technical requirements See par. 4 for manufacturers and products. Total Electrostatic painting with pure polyester 80 See par. 4.2 for manufacturers. See par. 5 technical requirements.

5 CHIEF CHEMIST DEPT. PAGE No Paint manufactures and products 4.1 Wet painting procedure Primer Product name Manufacturer Remarks Epitamarin Uniseal brown Tambour code 842-xx Epogal Tambour code 644- xxcode 644-xx Epoxy Primer 524 Rust Bond Penetrating Amercoat tc 71 Duraplate Intergard 269 Sigmarit sealer Sigma Cover Prim 7413 Vigor EP 201C Univercol Carboline AMERON SHERWIN WILLIAMS INTERNATIONAL Sigma Sigma Freitag Top coat TAMAGLASS Unicryl Carboline 134 Amercoat 450 S Sigma Dur HB Finish 7524 Vigor PU 239 Interthane990 Acrolom 218 TAMBOUR Univercol Carboline Ameron Sigma Freitag INTERNATIONAL SHERWIN WILLIAMS 4.2 Electrostatic painting

6 CHIEF CHEMIST DEPT. PAGE No. 6 Product name Manufacturer Remarks Polyester Shamir Tambour 185-xxx Polyester Unilac series 7700 Polyester Univercol 7700 David Powder 5. Technical Requirement for electrostatic painting Laboratory tests will be carried out on panels measuring 100 x 150 x 0.7 mm. 5.1 Thickness of Coating At least 80 Microns. The test to be according to SSPC-PA1/ Adhesion Pull-off according to ASTM D Test dolly 20 mm. Using Acrylic Adhesive (DP-805, Scotch-weld or equivalent). Minimum 1000 psi. 5.3 Hardness Hardness of coating to scratching: 4000 gr. According to ISO R Impact According to ASTM D-2794: 25 Kg/cm. Will not be every cracking of the coating, nor any detachment from the substrate. 5.5 Extensibility ISO-1520-Erichsen Cupping: 6 mm without cracks or detachments. 5.6 Permeability

7 CHIEF CHEMIST DEPT. PAGE No. 7 A coated panel will be partially submerged in pressure cooker containing distilled water to a level of at least 25 mm. Cooking at least for two hours after the appearance of steam. After cooling of the cooker and the panel, the coating should be examined: no bubbles should appear on the surface. (They are acceptable only near the edges). 5.7 Resistance to Salt Spray Fog: Three panels will be placed in al salt water chamber for 1000 hours after being cross-cut in the center of the plate with an X, mm long. After drying for 24 hours at room temperature, adhesion to the cross-cut will be examined. Spread of rust along the lines and separation of the coating must not exceed 2 mm. There must be no bubbles or rust spots on the surface remote from the cut and the edges of the plate. 6. Quality assurance Is based on the authorization of the process and manufacturer that shall be granted after ability to supply panels that will conform with the requirements specified in par.5. During the fabrication only thickness off the coating will be checked. There are not permited measurements under the specified thickness in par.5.1. REMARKS.1 Damaged hot dip galvanized surfaces must be repaired by applying at least two coats of organic zinc rich coatings to give a minimum dry film thickness of 60 micron. Approved products: Z.R.C I.E.C distributor carmel andasa catalog no ZINGA -distributor m.b.l catalog no ZINC-GLAD 5 - distributor Chemital. catalog no GLAVIT 90 E distributor tambour catalog no In the painting system will be involved only paints from the same manufacturer 3. Every two successive coats must be colour contrasted.

8 CHIEF CHEMIST DEPT. PAGE No Surface profile producing media recommended: non-woven abrasive wheels and discs such as: 3 M Scotch-Brite clean strip discs and wheels. Coated abrasive discs (sending pads) as: Flap wheels such as: Grind 0 Flex Wheels from Merit Corporation Needle guns consisting of a bundle of wire needles which can impact a surface. 5. Phone number of the manufacturers: - Tambour Paints Ltd Univercol Ltd zinc glad.products-distributor-chemital Carboline Distributor LESHEM TAASIOT Ameron Distributor Chemarine Freitag Distributor ARAD ANDASA David Powder Ltd ZRC Distributor carmel andasa ZINGA-distributor MBL iternational distributor marcot Prepared: Y. Casapu Approved: Dr. E. Sutskover

SPECIFICATION FOR PAINTING ON GALVANIZED SURFACES BY WET or ELECTROSTATIC POWDER PAINTING

CHIEF CHEMIST DEPT. PAGE No. 1 of 7 SPECIFICATION FOR PAINTING ON GALVANIZED SURFACES BY WET or ELECTROSTATIC POWDER PAINTING 1. SCOPE This specification covers the requirements for painting of steel surfaces