1、SSPC-Paint 20April 1, 2002Editorial Revisions November 1, 20046-491. Scope1.1 This specifi cation covers two types of highly pigmented zinc-rich coatings that are uniquely defi ned by their capabili-ties for protecting steel exposed at fi lm discontinuities such as narrow scratches and holidays.1.2
2、The vehicle type may be inorganic (Type I) or organic (Type II).1.3 This specifi cation does not cover weldable precon-struction primers such as SSPC-Paint 30.1.4 Zinc-rich coatings, both topcoated and untopcoated, have been used successfully in a wide variety of environmental zones. For a detailed
3、breakdown of applicability of various types of zinc-rich coatings in different environmental zones, refer to SSPC-PS Guide 12.00. Consult the coating manufacturer for specifi c exposure recommendations (see Note 12.1).1.5 This coating is intended for application by spray for use by itself or as a pr
4、imer in a multi-coat system.2. Description2.1 USE OF SPECIFICATION2.1.1 Primers meeting this specifi cation are categorized according to vehicle type and zinc level. 2.1.2 If no vehicle type is specifi ed, either Type I (Inorganic) or Type II (Organic) is acceptable (see Section 2.3).2.1.3 If no zin
5、c level is specifi ed, zinc levels 1, 2, and 3 are acceptable (see Section 2.5).2.2 COMPOSITION: The coating described in this specifi cation consists of zinc dust, functional additives, and an organic or inorganic binder with appropriate solvents (see Note 12.2).2.3 VEHICLE TYPES2.3.1 Type I-A, ino
6、rganic post-curing vehicleswater-soluble, include materials such as alkali metal silicates, phosphates, and modifi cations thereof that must be subsequently cured by ap-plication of heat or a solution of a curing compound (or curing solution).2.3.2 Type I-B, inorganic self-curing vehicleswater-reduc
7、ible include water-soluble alkali metal silicates, quaternary ammonium silicates, phosphates, and modifi cations thereof. These coatings cure by a reaction among the zinc, silicate, steel substrate, and naturally occurring carbon dioxide during and after evaporation of water from the coating.2.3.3 T
8、ype I-C, inorganic self-curing vehiclessolvent-reducible, include titanates, organic silicates, and polymeric modifi cations of these silicates. These systems are dependent upon moisture from the atmosphere to complete hydrolysis, forming the titanate- or polysilicate-zinc reaction product.2.3.4 Typ
9、e II, organic vehicles covered by this specifi cation may be chemically cured or may dry by solvent evaporation (see Note 12.3). Under certain conditions heat may be used to facilitate or accelerate drying and curing. 2.4 COMPONENTS: These zinc dust primers may consist of one, two, or three componen
10、ts.2.5 ZINC DUST LEVEL CLASSIFICATION: The coating shall be classifi ed according to the level of zinc dust by weight present in the dried fi lm as follows:Level 1 equal to or greater than 85%Level 2 equal to or greater than 77% and less than 85%Level 3 equal to or greater than 65% and less than 77%
11、3. Referenced Standards3.1 The latest issue, revision, or amendment of the refer-enced standards in effect on the date of invitation to bid shall govern, unless otherwise specifi ed. Standards marked with an asterisk (*) are referenced only in the Notes, which are not requirements of this specifi ca
12、tion.3.2 If there is a confl ict between the requirements of any of the cited referenced standards and this specifi cation, the requirements of this specifi cation shall prevail.SSPC: The Society for Protective CoatingsPAINT SPECIFICATION NO. 20Zinc-Rich CoatingType I Inorganic and Type II OrganicSS
13、PC-Paint 20April 1, 2002Editorial Revisions November 1, 20046-503.3 SSPC STANDARDS AND JOINT STANDARDS:Guide 13 Guide for the Identifi cation and Use of Industrial Coating Mate-rial in Computerized Product DatabasesPA 2 Measurement of Dry Coat-ing Thickness with Magnetic Gages* Paint 29 Zinc Dust Sa
14、crifi cial Primer, Performance-BasedPaint 30 Weld-Through Inorganic Zinc PrimerSP 1 Solvent CleaningSP 5/NACE No. 1 White Metal Blast CleaningPS Guide 12.00 Guide to Zinc-Rich Coating Systems* PS 12.01 One-Coat Zinc-Rich Painting System3.4 ASTM INTERNATIONAL STANDARDS:1A 572 Standard Specifi cation
15、for High-Strength Low-Alloy Columbium-Vanadium Structural SteelB 117 Practice for Operating Salt Spray (Fog) ApparatusD 185 Test Methods for Coarse Particles in Pigments, Pastes, and PaintsD 520 Specifi cation for Zinc Dust Pigment* D 562 Test Method for Consistency of Paints Measusring Krebs Unit (
16、KU) Viscosity Using a Stormer-type ViscometerD 714 Standard Test Method for Evaluating Degree of Blistering of Paints* D 1296 Test Method for Odor of Volatile Solvents and Diluents* D 1308 Test Method for Effect of Household Chemicals on Clear and Pigmented Or-ganic Finishes* D 1475 Test Method for
17、Density of Liquid Coatings, Inks, and Related Products* D 1535 Practice for Specifying Color by the Munsell System* D 1640 Test Methods for Drying, Curing, or Film Formation of Organic Coatings at Room TemperatureD 1654 Test Method for Evaluation of Painted or Coated Specimens Subjected to Corrosive
18、 Environments* D 2369 Test Method for Volatile Content of Coatings* D 2371 Test Method for Pigment Content of Solvent-Reducible Paints* D 2621 Test Method for Infrared Identifi cation of Vehicle Solids from Solvent-Reducible PaintsD 3278 Test Methods for Flash Point of Liquids by Small-Scale Closed-
19、Cup ApparatusD 3359 Test Methods for Measuring Adhesion by Tape TestD 3925 Practice for Sampling Liquid Paints and Related Pigmented CoatingsD 4417 Test Methods for Field Measurement of Surface Profi le of Blast Cleaned Steel* D 5894 Practice for Cyclic Fog/UV Exposure of Painted Metal (Alternating
20、Exposures in a Fog/Dry Cabinet and a UV/Condensation Cabinet)3.5 AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI) STANDARD:2Z129.1 Hazardous Industrial ChemicalsPrecautionary Labeling3.6 FEDERAL SPECIFICATIONS AND STANDARDS:3FED-STD-141 Paint, Varnish, Lacquer and RelatedMaterials: Methods of Inspection
21、, Sampling and Testing* Method 3011 Condition in ContainerMethod 4331 Spraying Properties Method 4541 (canceled) Working Properties and Appearance of Dried Film4. Composition Requirements4.1 The manufacturer is given wide latitude in the selection of materials and manufacturing processes. 4.2 PIGMEN
22、TATION4.2.1 The major pigment component in these coatings is zinc dust of the type described in ASTM D 520 (see Note 12.4). The amount of zinc dust by weight present in the dried fi lm shall be as specifi ed in accordance with Section 2.5.4.2.2 Other pigment components may include extenders, curing
23、aids, tinting colors, and suspension and pot-life control agents.1 ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959.2 American National Standards Institute, 1819 L Street, NW, Suite 600, Washington, DC 20036. Standards downloadable from www.ansi.org.3 FED STD 141 Available
24、 from USA Information Systems, Inc. 1092 Laskin Road, Suite 208, Virginia Beach, Va. 23451. This standard is available on-line from .SSPC-Paint 20April 1, 2002Editorial Revisions November 1, 20046-515. Standard Testing Conditions5.1 TEST PANELS: The hot rolled steel test panels shall conform to ASTM
25、 A 572. Panel size shall be 100 mm x 150 x 3.2 mm (4 x 6 x 1/8 inches) or greater. Test panels shall be solvent cleaned in accordance with SSPC-SP 1 prior to blast cleaning. The test panels shall be blast cleaned in accordance with SSPC-SP 5 and have a blast profi le of 44 to 57 micrometers (1.75 to
26、 2.25 mils). Measure the blast profi le in accordance with ASTM D 4417, Method C.5.2 APPLICATION: The coating shall be spray-applied as a single coat in accordance with the coating manufacturers written recommendations.5.3 DRY FILM THICKNESS: The dry fi lm thickness (DFT) of the test panels shall me
27、et the manufacturers written recom-mended minimum and shall not exceed the manufacturers stated minimum by more than 25 micrometers (1 mil). If there is no recommended fi lm thickness, then the thickness shall be 60 to 90 micrometers (2.5 to 3.5 mils). The DFT shall be measured in accordance with Ap
28、pendix 5 of SSPC-PA 2.5.4 CURE: The coating shall be dried and cured in accor-dance with manufacturers written recommendations. Before any testing, all coated panels shall be aged for a minimum of 30 days in an environment with a minimum relative humidity of 55%.5.5 SCRIBING: Scribe two parallel lin
29、es on the face of the coated panels so as to expose the underlying metal before testing. The lines shall be at least 2.5 cm (1 inch) from the edge, the top, and the bottom of each panel and at least 5 cm (2 inches) from each other. Each scribe shall be at least 6 cm (2.4 inches) long. The scribes ma
30、y run vertically or at an angle across the face of the panel. Follow the scribe-making procedure described in ASTM D 1654.5.6 BACKS AND EDGES: Coat and seal all edges and the back side of each panel with a coating or tape that will provide the necessary protection to these surfaces.6. Requirements o
31、f Liquid Coating6.1 MIXING: The liquid portion of a multi-component coat-ing shall be mixed and dispersed to produce a product that is uniform, stable, free from grit, and in conformance with the requirements of this specifi cation.6.1.1 The pigment portion of a multi-component coating (if supplied
32、as a dust) shall be dry and loosely packed prior to mixing.6.1.2 The ready-mixed coating shall be capable of being dispersed under mechanical agitation to a smooth, uniform consistency and shall not show any objectionable properties in the mix. 6.1.3 After mixing, all types of coarse particles and s
33、kins as residue retained on a standard 60 mesh screen shall be no more than 0.5% by weight of the total coating, regardless of type, in accordance with ASTM D 185. If required for new technology coatings, an alternate screen size may be agreed to among the contracting parties.6.2 POT LIFE: The pot l
34、ife of a multi-component zinc-rich coating, when mixed and ready for application in accordance with the manufacturers written instructions, shall not be ex-ceeded. Pot life with adjustments for temperature and humidity shall be provided by the coating manufacturer. Properly mixed and applied materia
35、l used up to the end of the pot life shall pass the adhesion test described in Section 7.2. 6.3 STORAGE LIFE: Neither the vehicle of the multi-component coating nor the ready-mixed coating shall show thickening that is detrimental to performance or application properties. The components or coating s
36、hall exhibit no curdling, gelling, gassing, or hard caking after being stored unmixed for a minimum of six months from date of delivery in a tightly sealed, unopened container at a temperature of 10 to 32C (50 to 90F).6.4 WORKING PROPERTIES: The mixed coating shall spray easily and show no signs of,
37、 streaking, running, sagging, or other objectionable features when applied within the coating manufacturers recommended fi lm thickness range and tested in accordance with FED-STD-141, Methods 4331 and 4541.6.5 FLASH POINT: The minimum fl ash point, as deter-mined by ASTM D 3278, should be “none” fo
38、r inorganic water-based zinc dust coatings, and a minimum of 4.4C (40F) for solvent- based inorganic zinc primers (Type I) and for organic zinc primers (Type II).7. Laboratory Physical Tests of Applied Films7.1 MUDCRACKING: The coating, when applied and aged in accordance with Sections 5.1, 5.2, and
39、 5.4 to a 125 micrometer (5 mil) minimum dry fi lm thickness, shall show no signs of mudcracking visible to the eye unaided by magnifi ca-tion.7.2 ADHESION: The coating, when applied, dried, and cured in accordance with Section 5, shall be tested per ASTM D 3359, Method B. There shall be no separati
40、on of the coating or delamination of an entire square. Loss of adhesion around the perimeter due to cutting of each square is acceptable. The adhesion rating shall be no less than grade 4B.SSPC-Paint 20April 1, 2002Editorial Revisions November 1, 20046-528. Accelerated Laboratory Weathering Test8.1
41、SALT FOG EXPOSURE TEST: Triplicate panels prepared in accordance with Section 5 shall be exposed in a salt fog cabinet in accordance with ASTM B 117. Inorganic coatings (Type I) shall be exposed for 3000 hours and organic coatings (Type II) shall be exposed for 1000 hours (aee Notes 12.5 and 12.6).8
42、.1.1 Rust Evaluation: After the specifi ed exposure time, each replicate panel shall have no rusting of the coated portion. Slight rusting in the scribe mark is permissible and resulting staining should be ignored. Strips 6 mm (1/4 in) wide along the edges of the panel may be ignored.8.1.2 Blister E
43、valuation: After the specifi ed exposure time, there shall be no blistering for Type I coatings; medium blistering is permitted for Type II coatings per measurement guidelines of ASTM D 714.8.1.3 Scribe Evaluation: After the specifi ed exposure time, there shall be no undercutting from the scribe.9.
44、 Labeling9.1 Labeling shall conform to ANSI Z129.1.9.2 Technical data shall be provided for at least all data elements categorized as “essential” in SSPC-Guide 13.10. Inspection10.1 All materials supplied under this specifi cation are subject to timely inspection by the purchaser or his authorized r
45、epresentative. The purchaser shall have the right to reject any materials supplied that are found to be defective under this specifi cation (see Notes 12.7 and 12.8). In case of dis-pute, unless otherwise specifi ed, the arbitration or settlement procedure established in the procurement documents sh
46、all be followed. If no arbitration procedure is established, then a procedure mutually agreeable to the purchaser and material supplier shall be used. 10.2 Samples of paints may be requested by the pur-chaser and shall be supplied upon request along with the manufacturers name and identifi cation fo
47、r the materials. Samples may be requested at the time the purchase order is placed or may be taken from unopened containers at the job site.10.3 Unless otherwise specifi ed, the sampling shall be in accordance with ASTM D 3925.11. Disclaimer11.1 While every precaution is taken to ensure that all inf
48、ormation furnished in SSPC standards and specifi cations is as accurate, complete, and useful as possible, SSPC cannot assume responsibility nor incur any obligation resulting from the use of any materials, coatings, or methods specifi ed herein, or of the specifi cation or standard itself.11.2 This
49、 specifi cation does not attempt to address prob-lems concerning safety associated with its use. The user of this specifi cation, as well as the user of all products or practices described herein, is responsible for instituting appropriate health and safety practices and for ensuring compliance with all governmental regulations.12. NotesNotes are not requirements of this specifi cation.12.1 USES: This primer covers a range of vehicle types (inorganic/organic, water-borne/solvent-borne, one-pack/two-pack/three-pack, chemical curing/thermoplastic). A detai
