AWWA-C224-2002.pdf
American Water Works Association (1 st Edition) ANSIIAWWA C224-O1 AWWA STANDARD FOR TWO-LAYER NYLON-11 -BASED POLYAMIDE COATING SYSTEM FORTHE INTERIOR AND EXTERIOR OF STEEL WATER PIPE, CONNECTIONS, FIlTINGS, AND SPECIAL SECTIONS L II i r n -#a# Americen National Standards Instiiuie Effective date: March 1, 2002. First edition approved by AWWA Board of Directors June 17, 2001. Approved by American National Standards Institute: Dec. 21,2001. AMERICAN WATER WORKS ASSOCIATION 6666 West Quincy Avenue, Denver, Colorado 80235 www.awwa.org Copyright American Water Works Association Provided by IHS under license with AWWA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/21/2007 07:29:14 MDTNo reproduction or networking permitted without license from IHS -,-,- AVWVA Standard This document is an American Water Works Association (AWWA) standard. It is not a specification. AWWA standards describe minimum requirements and do not contain all of the engineering and ad- ministrative information normally contained in specifications. The AWWA standards usually contain options that must be evaluated by the user of the.standard. Until each optional feature is specified by the user, the product or service is not fully defi (212) 642-4900. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information or retrieval system, except in the form of brief excerpts or quotations for review purposes, without the written permission of the publisher, Copyright O 2001 American Water Works Association Printed in USA 11 Copyright American Water Works Association Provided by IHS under license with AWWA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/21/2007 07:29:14 MDTNo reproduction or networking permitted without license from IHS -,-,- Committee Personnel The Steel Water Pipe Manufacturers Technical Advisory Committee Task Group (SWPMTAC) on C224, which developed this edition, had the following personnel at the time: Page. McAndrew, Chair Mike Bauer, Tnemec Company Inc., Kansas City, Kan. Page McAndrew, Autofina Chemicals, King of Prussia, Penn. Mike Sangalli, Smith-Blair Inc., Texarkana, Texas M.C. Siminski, Morton Powder Coatings, Reading, Penn. (AWWA) (AWWA) (AWWA) (AWWA) H.R. Stoner, Consultant, North Plainfield, N.J. Martin Topps, Glynwed Pipe Systems, Hixson, Tenn. J.A. Wise, Canus Industries Inc., Port Coquitlam, B.C. The AWWA Standards Committee on Steel Pipe, which reviewed and approved this standard, had the following personnel at the time of approval: George J. Tupac, Chair John H. Bambie Jr., Vice-Chair Dennis A. Dechant, Secretary Consumer Members G.A. Andersen, New York City Bureau of Water Supply, Corona, New York J.H. Bambei Jr., Denver Water, Denver, Colo. D.W. Coppes, Massachusetts Water Resources Authority, Boston, Mass. R.V. Frisz, US Bureau of Reclamation, Denver, Colo. T.J. Jordan, Metropolitan Water District of Southern California, La Verne, Calif T.A. Larson, Tacoma Water Division, Tacoma, Wash. A.L. Linard, Los Angeles Department of Water therefore, it is the manufacturers and purchasers responsibility to verify the current requirements of federal, state, and local regulations. Sec. 4.3 Primer Only those primers approved by the coating manufacturer may be used in the production of a polyamide coating system. Specifics of shelf life and proper storage of a primer shall be provided by the manufacturer. Sec. 4.4 Polyamide Powder 4.4.1 Properties. The polyamide powder employed in the production of polyamide coating shall be a single-component product, composed of principally Nylon-11, fillers, colorants, antioxidants, and other materials, so that when employed Copyright American Water Works Association Provided by IHS under license with AWWA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/21/2007 07:29:14 MDTNo reproduction or networking permitted without license from IHS -,-,- TWO-LAYER NYLON-11-BASED POLYAMIDE COATING SYSTEM 5 according to the specifications of the manufacturer, produces a uniform, continuous coating that complies with all requirements of this standard. The properties of this polyamide powder shall comply with all the requirements of Table 1. 4.4.2 Shelf life and storage. Specifics of shelf life and proper storage of the polyamide powder described in Sec. 4.4.1 shall be provided by the manufacturer. 4.4.3 Application capability. When applied by a method specified by the manufacturer, the polyamide powder described in Sec. 4.4.1 shall produce, after appropriate thermal treatment, a uniform coating having a thickness that complies with the requirements written in Table 2 and Sec. 4.5.3.3. Sec. 4.5 Coating Application 4.5.1 General. Polyamide coatings shall be applied by a method specified by the manufacturer. When the same coating is to be applied to both the internal surface and external surface of the steel article, it is usually preferable to employ the method of immersion in a fluidized bed. When the coating is to be applied to either the internal surface or the external surface of a steel article, but not both, it is usually preferable to employ either the method of electrostatic spray or the method of spray onto a preheated article. When different coatings are used for internal surface and external surface, it may be preferable to employ the method of rotocoating (a method whereby the coating is applied to the interior surface of a pipe by rotating the pipe heated with polyamide powder inside). Note, however, that because elevated temperatures are required to perform rotocoating, coatings that have been applied prior to rotocoating may be damaged. Table 1 systems Properties of polyamide powder employed in the production o f polyamide coating Minimum Maximum ASTM Value Value Method Specific Gravity at 73°F (g/cm3) 1.05 1.20 D-792 Particle Size Distribution (weight percent retained on a No. 100 mesh screen) Melting Point (“CPF) Water Absorption (weight percent) D-1921 5 45 182/360 19 ll3 76 E-324 1.0 2.7 D-570 - - Amount of Poly (1 1-aminoundecanoic acid) (weight percent) 70 Inherent Viscosity (deciliterdg) (a) 0.72 - D-789 NOTE: Inherent viscosity is measured at 20°C on a 0.5% (by weight) solution of polyamide powder dissolved in meta-cresol. Alternatively, this requirement shall be satisfied if the Nylon-11 resin from which polyamide powder is produced has a minimum value of inherent viscosity (measured under the exact same conditions as just cited) of 0.82 deciliterdg. Copyright American Water Works Association Provided by IHS under license with AWWA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/21/2007 07:29:14 MDTNo reproduction or networking permitted without license from IHS -,-,- 6 AWWAC224-O1 Table 2 Thicknesses of polyamide coating systems Minimum Maximum Value Value Standard Reference Thickness (rnilsXa) Method (Section) Exterior and Interior by fluidized bed, electrostatic spray, or spray onto preheated article (b) -pipes, connections, fittings, special sections, other articles 9 (c) 24 SSPC PA-2 4.5.3.3 Interior Only by fluidized bed, electrostatic spray, or spray onto preheated article -pipes 9 (cl 24 SSPC PA-2 4.5.3.3 Interior Only by rotocoating -pipes, connections, fittings, special sections, other articles 14 40 SSPC PA-2 4;5.3.3 Exterior Only by fluidized bed, electrostatic spray, or spray onto preheated article (b) -pipes, connections, fittings, special sections, other articles 9 (c) 40 SSPC PA-2 4.5.3.3 NOTES: 1. Thicknesses include both primer layer and polyamide layer. 2. In the case where the steel article is placed in a position where it may be subjected to a high level of mechanical abrasion/ impacüetc. (e.g., a cóated pipe placed underground and thus subject to a high level of abrasiodimpact from dirürock backfilling), the purchaser shall consult the manufacturer to obtain a recommendation for coating thickness. 3. in the case where a weld reinforcement is present, a minimum thickness of 12 mils shall apply. 4.5.2 Steel surface preparation. 4.5.2.1 Weld reinforcements. Weld reinforcements (i.e., the raised compo- nents of weld seams) in a steel article shall be deburred or may be removed when required by the purchaser, such that the area formerly under the weld reinforcement is flush to all adjacent surfaces. When performed, removal of weld reinforcements shall be performed prior to hydrostatic testing, surface cleaning, or abrasive blast cleaning. 4.5.2.2 Surface cleaning. Prior to the performance of abrasive blast cleaning, steel surfaces shall be inspected and, if required, cleaned according to SSPC SP-1 to remove oil, grease, or other adhering deposits. Care shall be taken to ensure that use of solvents complies with applicable local regulations. Heating to remove water and ice may be performed, provided that steel surfaces are heated in a manner that prevents distortion and other damage. If any contaminant remains after cleaning, more vigorous cleaning steps (e.g., chemical treatment) may be needed. 4.5.2.3 Abrasive blast cleaning. Abrasive blast cleaning shall be performed. It shall be performed in accordance with the specifications of SSPC SP-lO/NACE No. 2 in order to achieve a near-white surface. Copyright American Water Works Association Provided by IHS under license with AWWA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/21/2007 07:29:14 MDTNo reproduction or networking permitted without license from IHS -,-,- TWO-LAYER NYLON-1 1-BASED POLYAMIDE COATING SYSTEM 7 4.5.2.3.1 Visual standards. If required by the purchaser, before abrasive blast cleaning is performed, the constructor shall prepare representative samples of blast- cleaned surfaces (corresponding appropriately to the actual steel article) to serve as visual standards. The standards should have a minimum size of approximately 6 in. (150 mm) x 6 in. (150 mm). The visual standards meet the requirements of Sec. 4.5.2.3; the visual standards shall be wrapped in a clear protective wrap and properly sealed or otherwise protected from surface contamination and corrosion. The visual standards shall be used as a reference throughout the coating operation. Alternatively, other industry-accepted visual standards may be employed, such as those made available by NACE or SSPC (e.g., SSPC VIS 1-89), if specified by the purchaser. 4.5.2.3.2 Abrasive working mix. To ensure consistent surface preparations resulting from abrasive blast cleaning, only abrasive working mixes that are dry and free of oil, grease, and other contaminants (according to the specifications of SSPC AB-1) shall be used. 4.5.2.3.3 Surface profile. Abrasive blast cleaning shall be performed in order to achieve an angular profile of 1.5 mils (38 microns) to 4.0 mils (100 microns). 4.5.2.3.4 Surface inspection. Blast-cleaned steel surfaces shall be inspected visually for adequate surface preparation. Surface imperfections that include but are not necessarily limited to sharp edges, slivers, scabs, burrs, weld spatter, etc., shall be removed by hand filing, grinding, or another appropriate method, in order to prevent imperfections in subsequent polyamide coatings. After this, further surface cleaning according to the requirements of Sec. 4.5.2.2 or 4.5.2.3 may be required. 4.5.2.4 Protection of surfaces. Blast-cleaned steel surfaces shall be handled and stored so that no corrosion or surface deterioratiodcontamination is permitted to occur prior to coating. If surface deterioratiodcontamination should occur, then surfaces shall be recleaned according to the requirements of Sec. 4.5.2.2 and 4.5.2.3. 4.5.2.5 Primer application. Primer (Sec. 4.3) shall be applied to steel surfaces according to the primer manufacturer?s specifications. Only those primers that are approved for use by the coating manufacturer may be used. Primers may be in either liquid form or powder form. The thickness of the resultant primer layer shall be measured according to and be in accordance with the manufacturer?s specifications. The constructor shall ensure that after performance of all steps involved in primer application, but prior to application of polyamide powder, no corrosion or surface deterioratiodcontamination of the primed steel surface is permitted to occur. If such Copyright American Water Works Association Provided by IHS under license with AWWA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/21/2007 07:29:14 MDTNo reproduction or networking permitted without license from IHS -,-,- 8 AWWAC224-01 corrosion or surface deterioratiodcontamination should occur, the steel surface shall be reprocessed according to the requirements of Sec. 4.5.2.2 and 4.5.2.3. 4.5.3 Coating application-specific. Polyamide coatings may be applied onto steel surfaces by any method specified by the manufacturer and approved by the purchaser. Acceptable methods are electrostatic spray, immersion in a fluidized bed, spray onto a preheated article, and rotocoating. 4.5.3.1 Heating. For the purpose of coating as written in Sec. 4.5.3, steel surfaces that have been prepared in accordance with the requirements of Sec. 4.5.2 shall be heated in accordance with the specifications of the coating manufacturer. Temperature limits and exposure time limits at defined temperatures shall not be exceeded for the purpose of preventing coating degradation. If temperature limits or exposure time limits are exceeded, it may be necessary to recoat or discard the steel article. To verify that temperature limits are not exceeded, surface temperatures of representative steel articles shall be examined periodically every four hours. Temperatures may be examined with any established method to verify that the heating source does not contaminate the steel surface or the polyamide coating. 4.5.3.2 Pipe ends. The polyamide coating may be held back (e.g., approxi- mately 2.5 in. 64 mml * 0.5 in. 13 mm) from either end, on both the exterior surface and interior surface. The presence of any coating material on the area held back, bevel or land, is not acceptable. In the case of coating of plain-end pipes where joints with rubber gaskets or mechanical couplings are to be used, coating to the edge of the pipe is acceptable, unless specified otherwise by the purchaser. 4.5.3.3 Thickness. The thickness of polyamide coating that is needed for a particular application should be chosen pursuant to consultation between the purchaser and the manufacturer. The minimum thickness at which polyamide coatings shall be employed is 9 mils (225 microns), for both exterior and interior surfaces. More specific requirement
