3 coat specs

8/18/2019 3 Coat Specs

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Duncan, OK

Specification: 68.00110 Revision: R

Date: November 3, 2010

Specification – Paint – Steel – Multi-Coat System With Organic Zinc-Rich Primer – For Off-

Shore and Coastal Areas

PRINTED DOCUMENTS ARE UNCONTROLLED

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1. Scope

1.1 This specification governs requirements for the application of a paint system designed to protect steelagainst corrosion in coastal and off-shore marine environments. Color requirements should be specified in the

applicable drawing notation or project specification.

Note: This specification replaces 68.00101.

1.2 This specification should not be used to paint non-ferrous metals such as aluminum, copper, and galvanized.Refer to specifications 68.00103 and 68.00104 for painting these materials. This specification may be used

exclusively to paint steel equipment when stainless steel components comprise a small percentage of the totalsurface area. Caution: Although the maximum service temperature of this paint system is 300°F, zinc-rich primermust not be used on stainless steel parts that could be exposed to temperatures above 780°F due to the potentialfor liquid metal embrittlement caused by melted zinc particles. Large surface areas of bare stainless steel shouldbe painted in accordance with specifications 68.00103 and 68.00104. Specification 68.00102 should be usedwhen painting over existing coatings on any material.

1.3 The paint system required by this specification is normally applied to bare blast-cleaned steel on new orpreviously existing equipment, components, and structures. Due to manufacturing constraints, most newequipment received for painting at the Duncan Manufacturing Center paint shop will have been assembled from

components already painted in accordance with this specification.

This equipment will require spot repair and touch-up in accordance with paragraphs 4.4 and 6.6.

1.4 The paint manufacturer or Duncan Technology Center metallurgy team shall be contacted with

any questions concerning surface preparation, the use or application of the coating material, mixing, applicationconditions, drying schedules, or equipment.

2. Referenced Documents (Latest Revision)

2.12.1.1 68.00103 (Duncan) – Paint System for Non-Ferrous Metals, Brush-Blasted2.1.2 68.00104 (Duncan) – Paint System for Non-Ferrous Metals, Not Brush-Blasted2.1.3 68.00102 (Duncan) – Paint System, 2-Coat2.1.4 68.00121 (Duncan) – Approved Paint Products2.1.5 AE-C-001 (Arbroath) – Organic Zinc Rich Primer2.1.6 AE-C-004 (Arbroath) – Multipurpose Primer

2.1.7 AE-C-003 (Arbroath) – Polyurethane Topcoat

2.2 SSPC: The Society for Protective Coatings Standards 2.2.1 SP 1 – Solvent Cleaning2.2.2 SP 10/NACE No. 2 – Near-White Metal Blast Cleaning2.2.3 VIS 1 – Dry Abrasive Blast Cleaning Guide and Reference Photographs2.2.4 SP 2 – Hand Tool Cleaning2.2.5 SP 3 – Power Tool Cleaning2.2.6 SP 11 – Power Tool Cleaning to Bare Metal2.2.7 PA 2 – Measurement of Dry Coating Thickness with Magnetic Gages


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2.3 ISO International Standards 2.3.1 8501-1 – Visual Assessment of Surface Cleanliness, Steel Preparation Grades2.3.2 8503-1 – Surface Roughness Characteristics of Blast-Cleaned Steel Substrates, Comparators

2.4 ASTM Standards 2.4.1 D4417 – Field Measurement of Surface Profile of Blast Cleaned Steel2.4.2 D4414 – Measurement of Wet Film by Notch Gages

3. Coating Materials

3.1 Coatings and Film Thickness

3.1.1 First Coat - organic zinc-rich primer – 3 to 4 mils (76-102 microns). See paragraph 6.4.3.1.2 Second Coat - epoxy primer – 3 to 4 mils (76-102 microns).3.1.3 Third Coat - polyurethane color coat – 2 to 3 mils (51-76 microns).3.1.4 Clear Coat - polyurethane clear coat – 0.5 to 1.5 mils (13-38 microns). See paragraph 6.7.

3.2 The coatings listed in 3.1.1, 3.1.2, and 3.1.3 are required as a minimum on steel painted in accordance withthis specification, except as noted in 1.3. See paragraph 6.7 for use of clear coat.

3.3 The paint system in 3.1 shall be comprised of approved products given in specification 68.00121.

3.4 Without clear coat, this specification is equivalent to the combination of Arbroath Specs AE-C-001, AE-C-004, and AE-C-003.

4. Surface Preparation Procedure

4.1 All weld spatter will be removed. All welds that are not smooth shall be ground smooth.

4.2 All visible oil, grease, soil, drawing and cutting compounds, and other soluble contaminants shall be removedin accordance with SSPC-SP 1 (Solvent Cleaning). Surfaces known or suspected to be contaminated withchlorides or salt deposits should be steam cleaned, pressure-washed, or scrubbed with a stiff brush using fresh

water.

4.3 Except as noted in paragraph 4.4, all steel surfaces shall be prepared by blast cleaning to a minimum of"Near-White" in accordance with SSPC-SP 10/NACE No. 2 or ISO 8501-1 Sa 2-1/2. The surface profile producedby blast cleaning shall be 2.0 +/- 0.5 mils (51 +/-13 microns). Visually compare the blast cleaned surface withappropriate standard as per Method-A of ASTM D4417 or ISO 8503-1. Visual standard SSPC-VIS 1 should beused in conjunction with the applicable surface preparation standard to verify surface condition. Surface profileshould be checked at least once per shift.

4.4 The following procedures shall be used when blast cleaning is impractical due to structural configuration orunsuitable for use on new equipment with components that may be damaged or contaminated by grit.

4.4.1 Bare metal surfaces such as welds, joints, connections, and structural attachments shall be hand

tool cleaned (SSPC-SP 2) or power tool cleaned (SSPC-SP 3) as required to remove loosely adherentmaterials. These surfaces shall be further prepared by power tool cleaning to bare metal in accordance withSSPC-SP 11.4.4.2 All loose or damaged paint shall be removed with hand or power tools back to a tightly adherentpaint surface and feather-edged.4.4.3 Painted surfaces shall be mechanically abraded with hand or power tools to provide a uniformlyroughened surface for subsequent topcoats. Except for leveling out uneven surfaces, mechanical abradingis not required to roughen fully cured polyurethane topcoats that will be coated with an adhesion promoter(see paragraph 6.6).


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5. Equipment

5.1 The coating applicator shall ensure that equipment is adequately sized and in proper operating order foreach application.

5.2 Spray equipment, lines, etc., must be clean. The compressed air used for blasting and spraying shall be freeof contamination by oil and water.

5.3 If necessary, the paint or equipment manufacturer should be consulted for pressure data (air and fluid) forconventional spraying or when using airless equipment.

6. Paint Application

6.1 Each paint product shall be properly catalyzed and mixed in accordance with the paint manufacturer'srecommendations prior to application.

6.2 The total dry film thickness (DFT) range for this paint system shall be 8 to 13 mils (203 to 330 microns).See paragraph 3.1 for target DFT ranges for individual coatings. In order to achieve the properDFT, wet film thickness measurements (WFT) should be performed during the application of eachcoat in accordance with ASTM D4414. Dry film thickness measurements should be performed in accordance with

SSPC-PA 2. Unless otherwise specified, reporting of film thickness measurements is not required.

6.3 Each coat of the system should normally be applied according to the coating manufacturersrecommendations and should be allowed the proper drying time before the application of subsequent coats.The recommended application conditions such as temperature and humidity must be observed. The temperatureof the steel surface shall be at least 5°F (3°C) above the dew point, and not falling, prior to painting.

6.4 The zinc-rich primer shall only be applied to a bare, blast-cleaned steel surface. When applying the zinc-rich primer, the coating must be constantly stirred by use of a constant agitation pot to prevent settling of zincparticles.

6.5 To reduce the possibility of pin-holing and blistering, a mist coat consisting of a light coat of intermediateepoxy primer should be applied over the zinc primer. Allow a minimum of 5 minutes for the solvents to flash off.

This shall be done before application of the full thickness of wet film.

6.6 Epoxy primer shall be used to spot prime or touch-up welds, various joints and connections, small repairedor reworked areas, and unpainted structural attachments that have been power tool cleaned to bare metal. This isnormally required on new equipment that has been assembled from pre-painted components. Unless otherwisespecified, all paint accessible areas on this equipment shall receive one or more applications of polyurethane colorcoat after touch-up with epoxy primer. Dry film thickness for all touch-up and recoating shall meet therequirements of paragraph 6.2. Adhesion promoter 100035554 (Jones Blair 45000), when used in lieu ofmechanical abrading, shall be applied from 0.2 to 0.5 mils (5-13 microns) to components with fully curedpolyurethane topcoats prior to recoat.

6.7 All spray accessible surfaces on built equipment should receive an application of clear coat after the finalcolor coat has been applied. Separate parts and components shall not be clear coated unless otherwise specified.

Caution: excessive build-up of coating thickness may result in yellowing.

6.8 To ensure coating continuity, primers and topcoats should be applied by brush in areas that are difficult tospray or have restricted access. These areas should include but are not limited to edges, corners, bolts, nuts,fitting connections, brackets and welds. All brush-coating (striping) shall be performed prior to the primary sprayapplication.

6.9 Narrow crevices formed by joined structural components or discontinuous welds should be thoroughly spot-primed by brush coating and filled with paintable, high quality, polyurethane sealant (100035555-white or100035556-gray) or other suitable filler material.


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6.10 Coatings that undergo a change in consistency or appearance during application should be discarded. Thecatalyzed coating pot life must not be exceeded.

6.11 Prior to the application of a coat, any damage or defects in a previous coat shall be repaired. Completedcoating systems that are damaged shall be restored to the full system originally specified. Runs, sags, and dripswill be avoided.

7. Material Storage – The coating applicator shall ensure that the coating materials are stored securely, under cover,and within a temperature range that suits the product.

8. Material Control – Coating material that has deteriorated during storage as evidenced by a change in consistencyor appearance, (jellied, lumps, moisture, etc.), shall be discarded. All coatings shall be used in correct rotation,according to the manufacture date, with the latest stock used last.