AS-NZS-3750.21-2008.pdf

AS/NZS 3750.21:2008 Australian/New Zealand Standard Paints for steel structures Part 21: UndercoatSolvent-borne AS/NZS 3750.21:2008 Accessed by UNIVERSITY OF SOUTH AUSTRALIA on 20 May 2008 AS/NZS 3750.21:2008 This Joint Australian/New Zealand Standard was prepared by Joint Technical Committee CH-003, Paints and Related Materials. It was approved on behalf of the Council of Standards Australia on 19 March 2007 and on behalf of the Council of Standards New Zealand on 3 March 2007. This Standard was published on 19 May 2008. The following are represented on Committee CH-003: AUSTROADS Australasian Corrosion Association Australian Paint Approval Scheme Australian Paint Manufacturers Federation Australian Pipeline Industry Association Business New Zealand Engineers Australia Institution of Professional Engineers New Zealand Master Painters Australia Master Painters New Zealand Association National Association of Testing Authorities Australia Water Corporation Western Australia Keeping Standards up-to-date Standards are living documents which reflect progress in science, technology and systems. To maintain their currency, all Standards are periodically reviewed, and new editions are published. Between editions, amendments may be issued. Standards may also be withdrawn. It is important that readers assure themselves they are using a current Standard, which should include any amendments which may have been published since the Standard was purchased. Detailed information about joint Australian/New Zealand Standards can be found by visiting the Standards Web Shop at www.standards.com.au or Standards New Zealand web site at www.standards.co.nz and looking up the relevant Standard in the on-line catalogue. Alternatively, both organizations publish an annual printed Catalogue with full details of all current Standards. For more frequent listings or notification of revisions, amendments and withdrawals, Standards Australia and Standards New Zealand offer a number of update options. For information about these services, users should contact their respective national Standards organization. We also welcome suggestions for improvement in our Standards, and especially encourage readers to notify us immediately of any apparent inaccuracies or ambiguities. Please address your comments to the Chief Executive of either Standards Australia or Standards New Zealand at the address shown on the back cover. This Standard was issued in draft form for comment as DR 04193. Accessed by UNIVERSITY OF SOUTH AUSTRALIA on 20 May 2008 AS/NZS 3750.21:2008 Australian/New Zealand Standard Paints for steel structures Part 21: UndercoatSolvent-borne COPYRIGHT © Standards Australia/Standards New Zealand All rights are reserved. No part of this work may be reproduced or copied in any form or by any means, electronic or mechanical, including photocopying, without the written permission of the publisher. Jointly published by Standards Australia, GPO Box 476, Sydney, NSW 2001 and Standards New Zealand, Private Bag 2439, Wellington 6020 ISBN 0 7337 8696 0 Originated as SAA Int 2261953. Revised and redesignated AS K1271961. Revised and redesignated AS 4025.21993. Revised and redesignated AS/NZS 3750.21:2008. AS/NZS 3750.21:2008 Accessed by UNIVERSITY OF SOUTH AUSTRALIA on 20 May 2008 AS/NZS 3750.21:2008 2 PREFACE This Standard was prepared by the Joint Standards Australia/Standards New Zealand Committee CH-003, Paints and Related Materials, to supersede AS 4025.21993, Paints for equipment including ships, Part 2: Solvent-borneInterior and exteriorUndercoat. See AS 3730.0 for other published Standards in this series. The terms normative and informative have been used in this Standard to define the application of the appendix to which they apply. A normative appendix is an integral part of a Standard, whereas an informative appendix is only for information and guidance. Accessed by UNIVERSITY OF SOUTH AUSTRALIA on 20 May 2008 3 AS/NZS 3750.21:2008 CONTENTS Page 1 SCOPE4 2 REFERENCED DOCUMENTS4 3 DEFINITIONS4 4 MATERIALS REQUIREMENTS.4 5 PACKAGING.9 6 LABELLING9 APPENDICES A LIST OF REFERENCED DOCUMENTS . 10 B PREPARATION OF TEST PANELS FOR RESISTANCE TO WEATHERING TESTS. 12 Accessed by UNIVERSITY OF SOUTH AUSTRALIA on 20 May 2008 AS/NZS 3750.21:2008 4 COPYRIGHT STANDARDS AUSTRALIA/STANDARDS NEW ZEALAND Australian/New Zealand Standard Paints for steel structures Part 21: UndercoatSolvent-borne 1 SCOPE This Standard sets out requirements for solvent-borne undercoat paints as part of a system for the protection of iron and steel against atmospheric corrosion. Typically available in white or grey colour, they are intended to be applied, as supplied, using brush, roller or by spray. This Standard applies to paints intended for the undercoating of metal surfaces primed in accordance with AS/NZS 3750.19 or AS/NZS 3750.20 that are to be topcoated with a semi- gloss or full gloss film in accordance with AS/NZS 3750.22 or AS/NZS 3750.23 that will provide resistance to weathering, washing and intermittent contact with petrol or mineral oils. Typical applications include machinery and the superstructures of ships. NOTE: Undercoats as part of a system for the protection of steel are not considered necessary according to AS/NZS 2312. However, for reasons such as additional filling properties, opacity, ease of sanding to obtain a finer finish, they may be incorporated in an alkyd system. 2 REFERENCED DOCUMENTS A list of documents referred to in this Standard is given in Appendix A. 3 DEFINITIONS The definitions of AS/NZS 2310 apply. 4 MATERIALS REQUIREMENTS NOTE: The properties and requirements for paint to this Standard are summarized in Table 1. 4.1 Composition The paint shall consist essentially of pigments, extenders, drying oils, modified resins such as alkyds or urethanes, and volatile hydrocarbon solvents such as mineral turpentine. The product shall not be a First, Second or Third Schedule paint as defined in the Standard for the Uniform Scheduling of Drugs and Poisons (SUSDP) issued by the Department of Health and Ageing. 4.2 Conditions of test Unless otherwise indicated, the requirements specified in this Standard apply to products that are tested under the following conditions: (a)The test panel material is tinplate as specified in AS/NZS 1580.104.1 or as indicated in Table 1. Where reference panels are required, they shall be composed of the same material as the test panel and be prepared by methods identical to those used for the test panel. (b)The size of test panels is as specified in Table 1 for the appropriate test method. (c)The method of test paint application is by brush. Accessed by UNIVERSITY OF SOUTH AUSTRALIA on 20 May 2008 5 AS/NZS 3750.21:2008 COPYRIGHT (d)The spreading rate of the paint should be as specified by the manufacturer, typically in the region of 16 m2/L. (e)Environmental conditions for testing are in accordance with AS/NZS 1580.101.5. (f)Environmental conditions for air-drying are in accordance with AS/NZS 1580.101.1. 4.3 Liquid paint 4.3.1 Condition in container When examined in accordance with AS/NZS 1580.103.1 at the time of delivery from the manufacturer or supplier, the paint shall be free from gel, coarse particles, skin and foreign matter. It shall readily yield a product of uniform consistency when manually re- incorporated in accordance with AS/NZS 1580.211.2. 4.3.2 Fineness of grind When determined in accordance with AS/NZS 1580.204.1, the fineness of grind shall not exceed 50 m. 4.3.3 Volume solids Where a volume solids requirement is specified, it shall be determined and expressed in accordance with AS 1580.301.2. 4.3.4 Susceptibility to formation of skin When the paint is tested in accordance with AS 1580.203.1, it shall not exhibit any skin formation. 4.3.5 Storage stability When housed under cover in the original unopened container at ambient temperatures for 18 months from the date of manufacture, and examined in accordance with AS/NZS 1580.103.1, the paint shall exhibit (a)a settlement rating of no less than 6, as defined in AS/NZS 1580.211.1; and (b)a uniform consistency free from lumps, gel, sediment and other visible defects after stirring, as described in AS/NZS 1580.211.2. The container shall not exhibit rust or other signs of corrosion on its interior surface. 4.3.6 Viscosity A sample of paint shall be prepared and tested in accordance with AS 1580.214.3, AS/NZS 1580.214.4 or AS/NZS 1580.214.5. The viscosity shall be recorded. 4.4 Application properties 4.4.1 General The applied film shall not run, streak, sag or exhibit undesirable roughness or grittiness when dry, regardless of the method of application used (see Clauses 4.4.2 to 4.4.4). 4.4.2 Brushing When applied to a test panel (see Clause 4.2) in accordance with AS/NZS 1580.205.1, the test paint shall exhibit satisfactory brushing properties and be free from defects. 4.4.3 Rolling When applied to a test panel (see Clause 4.2) in accordance with AS/NZS 1580.205.3, the test paint shall exhibit satisfactory rolling properties and be free from defects. Accessed by UNIVERSITY OF SOUTH AUSTRALIA on 20 May 2008 AS/NZS 3750.21:2008 6 COPYRIGHT 4.4.4 Spraying When thinned in accordance with the manufacturers instructions, and applied to a test panel (see Clause 4.2) in accordance with AS/NZS 1580.205.2 or AS/NZS 1580.205.4, the test paint shall exhibit good spraying properties and not clog the spray gun. 4.5 Applied film 4.5.1 Dry times When applied to the test panel using the appropriate spreading rate and tested in accordance with AS 1580.401.3, the test paint shall have a surface-dry time not exceeding 4 h, and a hard-dry time not exceeding 16 h. 4.5.2 Recoating properties and finish When a test panel, coated with test paint and air-dried for 20 h to 24 h, is recoated with a further coat of the test paint and is examined in accordance with AS 1580.603.1, there shall be no working up of the previous coat, and no development of any film defects during drying of the second coat. When examined after drying for a further 20 h to 24 h, the film shall be of uniform appearance and colour, and be free from wrinkling, frying and other visible defects. 4.5.3 Gloss When a coating of test paint which has been air-dried for 20 h to 24 h, is evaluated in accordance with AS/NZS 1580.602.2 using a 60-degree exposure head, the specular gloss shall not be greater than 50 gloss units. 4.5.4 Colour (Grey only) When a coat of test paint applied to a sealed cardboard test panel is air-dried for 20 h to 24 h and assessed in accordance with AS/NZS 1580.601.1, the colour of the panel shall be an approximate match to AS 2700 N32 Green Grey. 4.5.5 Opacity When the paint is applied to a test panel at a spreading rate of 16 m2/L and tested in accordance with (a)AS/NZS 1580.213.2, the contrast ratio of the paint shall be not less than 94 percent for white; or (b)AS/NZS 1580.213.1, the paint shall completely obscure the test pattern in one coat for grey. 4.5.6 Resistance to weathering 4.5.6.1 General When a test panel, prepared and coated in accordance with Appendix B, is continuously exposed at a 45 degree angle facing north for the appropriate period on an exposure rack complying with AS/NZS 1580.457.1 at an appropriate site (see Note), the system shall satisfy the requirements specified in Clause 4.5.6.2. NOTE: An appropriate site is one with climatic conditions that comply with Category E, Very High (E-M Marine) of AS/NZS 2312. 4.5.6.2 Weathering When test panels coated with the test paint have been exposed continuously for a 24-month period, under the conditions described in Clause 4.5.6.1, and assessed in accordance with the appropriate methods given in Table 2, the paint system shall meet the acceptance rating requirements of that table. Accessed by UNIVERSITY OF SOUTH AUSTRALIA on 20 May 2008 7 AS/NZS 3750.21:2008 COPYRIGHT 4.5.7 Resistance to solvents 4.5.7.1 General A test panel, prepared and cured for 7 d in accordance with AS/NZS 1580.101.1, shall satisfy the requirements of Clauses 4.5.7.2, 4.5.7.3 and 4.5.7.4. 4.5.7.2 Resistance to water When exposed and tested in accordance with AS/NZS 1580.455.1, the test panels shall exhibit: (a)No sign of blistering, wrinkling or other defects. (b)A scratch resistance, as determined by AS/NZS 1580.403.1, for the (i)immersed panel 0.6 kg; and (ii)un-immersed panel 0.8 kg. 4.5.7.3 Resistance to mineral oil When exposed and tested in mineral oil in accordance with AS 1580.454.1, the test panels shall exhibit: (a)No sign of blistering, wrinkling or other defects. (b)A scratch resistance, as determined by AS/NZS 1580.403.1, for the (i)immersed panel 0.6 kg; and (ii)un-immersed panel 0.8 kg. TABLE 1 SUMMARY OF REQUIREMENTS FOR SOLVENT-BORNE UNDERCOAT PAINT Typical test panels Clause Number Property assessed Performance requirement Test method Material Minimum size mm Free from gel, coarse particles, skin and foreign matter AS/NZS 1580.103.1 4.3.1 Condition in container Uniform consistency after manual re-incorporation AS/NZS 1580.211.2 N/A 4.3.2 Fineness of grind 50 m AS/NZS 1580.204.1 N/A 4.3.3 Volume solids By agreement AS 1580.301.2 N/A 4.3.4 Susceptibility to formation of skin No skin formation AS 1580.203.1 N/A Settlement 6 AS/NZS 1580.211.1 4.3.5 Storage stability (18 months) Uniform consistency free of lumps, gel, sediment or other defects AS/NZS 1580.211.2 N/A 4.3.6 Viscosity To be recorded AS 1580.214.3 or AS/NZS 1580.214.4 or AS/NZS 1580.214.5 N/A 4.4 Application properties No run, streak, sag, excessive roughness or grittiness AS/NZS 1580.205.1 AS/NZS 1580.205.2 AS/NZS 1580.205.3 AS/NZS 1580.205.4 Tinplate 500 × 500 (continued) Accessed by UNIVERSITY OF SOUTH AUSTRALIA on 20 May 2008 AS/NZS 3750.21:2008 8 COPYRIGHT Typical test panels Clause Number Property assessed Performance requirement Test method Material Minimum size mm 4.5.1 Surface-dry time Through-dry time 4 h 16 h AS 1580.401.3 Float glass 300 × 25 4.5.2 Recoating and finish Uniform colour and appearance No working up Free from wrinkling, frying and visible defects AS 1580.603.1 Tinplate 500 × 500 4.5.3 Gloss (60-degree exposure head) 50 gloss unit AS/NZS 1580.602.2 Float glass 150 × 250 4.5.4 Colour (Grey only) Approximate match to AS 2700 N32 Green Grey AS/NZS 1580.601.1 Sealed cardboard 50 × 100 Contrast ratio at 16 m2/L 94 percent AS/NZS 1580.213.2 Polyester film 90 × 120 4.5.5 Dry hiding power Obscure completely AS/NZS 1580.213.1 Black and white chart 0.1 m2 4.5.6 Resistance to weathering (coastal/marine) Resistance to weathering (coastal/marine) AS/NZS 1580.457.1 AS/NZS 1580.481.1 Primed steel 150 × 300 Free from blistering, wrinkling and other defects AS/NZS 1580.455.1 4.5.7.2 Resistance to water Scratch resistance immersed film 0.6 kg, un-immersed film 0.8 kg AS/NZS 1580.403.1 Tinplate 50 × 100 Free from blistering, wrinkling and other defects AS 1580.454.1 4.5.7.3 Resistance to minera