1、 AWWA Standard SM Large-Diameter Rubber- Seated Butterfly Valves, Sizes 78 In. (2,000 mm) and Larger Effective date: July 1, 2015. First edition approved by AWWA Board of Directors Feb. 12, 2006. This edition approved June 8, 2014. Approved by American National Standards Institute Mar. 23, 2015. ANS
2、I/AWWA C516-14 (Revision of ANSI/AWWA C516-10) Copyright 2015 American Water Works Association. All Rights Reserved. ii AWWA 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 o
3、f the engineering and administrative 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 defined. AWWA pub- lication
4、of a standard does not constitute endorsement of any product or product type, nor does AWWA test, certify, or approve any product. The use of AWWA standards is entirely voluntary. This standard does not supersede or take precedence over or displace any applicable law, regulation, or code of any gove
5、rnmental authority. AWWA standards are intended to represent a consensus of the water supply industry that the product described will provide satisfactory service. When AWWA revises or withdraws this standard, an official notice of action will be placed in the Official Notice section of Journal - Am
6、erican Water Works Association. The action becomes effective on the first day of the month fol- lowing the month of Journal - American Water Works Association publication of the official notice. American National Standard An American National Standard implies a consensus of those substantially conce
7、rned with its scope and provisions. An American National Standard is intended as a guide to aid the manufacturer, the consumer, and the general public. The existence of an American National Standard does not in any respect preclude anyone, whether that person has ap - proved the standard or not, fro
8、m manufacturing, marketing, purchasing, or using products, processes, or procedures not conforming to the standard. American National Standards are subject to periodic review, and users are cautioned to obtain the latest editions. Producers of goods made in conformity with an American National Stand
9、ard are encour - aged to state on their own responsibility in advertising and promotional materials or on tags or labels that the goods are produced in conformity with particular American National Standards. Caution n oti Ce : The American National Standards Institute (ANSI) approval date on the fro
10、nt cover of this standard indicates completion of the ANSI approval process. This American National Standard may be revised or withdrawn at any time. ANSI procedures require that action be taken to reaffirm, revise, or withdraw this standard no later than five years from the date of ANSI approval. P
11、urchasers of American National Standards may receive current information on all standards by calling or writing the American National Standards Institute, 25 West 43rd Street, Fourth Floor, New York, NY 10036; 212.642.4900; or emailing infoansi.org. ISBN-13, print: 978-1-62576-105-7 eISBN-13, electr
12、onic: 978-1-61300-342-8DOI: http:/dx.doi.org/10.12999/AWWA.C516.14 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 br
13、ief excerpts or quotations for review purposes, without the written permission of the publisher. Copyright 2015 by American Water Works Association Printed in USA hours of work by your fellow water professionals. Revenue from the sales of this AWWA material supports ongoing product development. Unau
14、thorized distribution, either electronic or photocopied, is illegal and hinders AWWAs mission to support the water community. This AWWA content is the product of thousands of Copyright 2015 American Water Works Association. All Rights Reserved. iii Committee Personnel The AWWA standards subcommittee
15、 for Large-Diameter Butterfly Valves that reviewed this stan- dard had the following personnel at the time of approval: John V. Ballun, Chair General Interest Members J.W. Green, Lockwood, Andrews are relatively easy to operate, even with moderate pressure drops across the valves; and require relati
16、vely little space for installation. I.B. History. The need for standardization of butterfly valves was recognized by the American Water Works Association (AWWA) with the adoption of AWWA C504 for Rubber-Seated Butterfly Valves in 1954. This companion standard was developed by the AWWA Standards Comm
17、ittee on Feb. 12, 2006, to meet the need for large-diameter valves in the waterworks industry. This second edition of ANSI/ AWWA C516 was approved by the AWWA Board of Directors on June 8, 2014. I.C. Acceptance. In May 1985, the US Environmental Protection Agency (USEPA) entered into a cooperative a
18、greement with a consortium led by NSF International (NSF) to develop voluntary third-party consensus standards and a certification program for direct and indirect drinking water additives. Other members of the original consortium included the Water Research Foundation (formerly AwwaRF) and the Confe
19、rence of State Health and Environmental Managers (COSHEM). The American Water Works Association (AWWA) and the Association of State Drinking Water Administrators (ASDWA) joined later. In the United States, authority to regulate products for use in, or in contact with, drinking water rests with indiv
20、idual states. Local agencies may choose to impose requirements more stringent than those required by the state. To evaluate the health effects of products and drinking water additives from such products, state and local agencies may use various references, including 1. An advisory program formerly a
21、dministered by USEPA, Office of Drinking Water, discontinued on Apr. 7, 1990. 2. Specific policies of the state or local agency. * American National Standards Institute, 25 West 43rd Street, Fourth Floor, New York, NY 10036. Persons outside the United States should contact the appropriate authority
22、having jurisdiction. Copyright 2015 American Water Works Association. All Rights Reserved. viii 3. Two standards developed under the direction of NSF * : NSF/ANSI 60, Drinking Water Treatment ChemicalsHealth Effects, and NSF/ANSI 61, Drinking Water System ComponentsHealth Effects. 4. Other reference
23、s, including AWWA standards, Food Chemicals Codex, Water Chemicals Codex, and other standards considered appropriate by the state or local agency. Various certification organizations may be involved in certifying products in accor- dance with NSF/ANSI 61. Individual states or local agencies have aut
24、hority to accept or accredit certification organizations within their jurisdictions. Accreditation of certi- fication organizations may vary from jurisdiction to jurisdiction. Annex A, “Toxicology Review and Evaluation Procedures,” to NSF/ANSI 61 does not stipulate a maximum allowable level (MAL) of
25、 a contaminant for substances not regulated by a USEPA final maximum contaminant level (MCL). The MALs of an unspecified list of “unregulated contaminants” are based on toxicity testing guidelines (noncarcinogens) and risk characterization methodology (carcinogens). Use of Annex A procedures may not
26、 always be identical, depending on the certifier. ANSI/AWWA C516 does not address additives requirements. Thus, users of this standard should consult the appropriate state or local agency having jurisdiction in order to 1. Determine additives requirements, including applicable standards. 2. Determin
27、e the status of certifications by all parties offering to certify prod- ucts for contact with, or treatment of, drinking water. 3. Determine current information on product certification. In an alternative approach to inadvertent drinking water additives, some juris- dictions (including California, M
28、aryland, Vermont, and Louisiana, at the time of this writing) are calling for reduced lead limits for materials in contact with pota- ble water. Various third-party certifiers have been assessing products against these lead content criteria, and a new ANSI-approved national standard, NSF/ANSI 372, D
29、rinking Water System ComponentsLead Content, was published in 2010. On Jan. 4, 2011, legislation was signed revising the definition for “lead free” within the Safe Drinking Water Act (SDWA) as it pertains to “pipe, pipe fittings, plumbing fit- tings, and fixtures.” The changes went into effect on Ja
30、n. 4, 2014. In brief, the new * NSF International, 789 North Dixboro Road, Ann Arbor, MI 48105. Both publications available from National Academy of Sciences, 500 Fifth Street, NW, Washington, DC 20001. Copyright 2015 American Water Works Association. All Rights Reserved. ix provisions to the SDWA r
31、equire that these products meet a weighted average lead content of not more than 0.25 percent. II. Special Issues. II.A. General. Conditions under which a valve is to be operated must be evaluated carefully by the purchaser. The evaluations must include the determination of the hydraulic characteris
32、tics of the system in which the valve will be installed and the operation of the valve (openclose or throttling), including (1) the maximum transient pressure and static differential pressure across the valve disc and (2) flow through the valve under the most adverse operating conditions. Torque req
33、uirements for valve operation vary considerably with differential pres- sure across the valve, fluid velocity, fluid temperature, and upstream piping conditions. Torque coefficients should be determined by the manufacturer using the methodology given in AWWA Manual M49, which recommends the use of s
34、cale models for predict- ing dynamic torques for large valves. Flow direction is important in the installation and use of a butterfly valve. Some valves performance and sealing characteristics vary with direction of flow. Flow direc- tion can affect the torque requirements and throttling characteris
35、tics of valves with offset discs or discs, which do not have identical surface configurations on each side. Many butterfly valves have different sealing characteristics on one side versus the other. A manufacturer may have a recommended high-pressure sealing side for long-term reliability. Hydraulic
36、 testing, flow capacities, and valve torques are based on the flow upstream of a valve being uniform and undisturbed, like the flow produced by a long length of constant-diameter straight pipe. Piping configurations that produce a nonuniform or turbulent flow pattern upstream of the valve can increa
37、se torque requirements, create damaging vibrations, increase head loss, and increase stresses in valve components. Some hydraulic systems can produce fluid velocities much higher than the maxi- mum of 16 ft/sec (4.9 m/sec) described in this standard. Typically, high fluid veloci- ties can result fro
38、m line breaks or in surge relief applications. The effects of high fluid velocities and asymmetrical turbulent flow conditions can result in high loads and torque requirements, which are unaccounted for in this standard. These design condi- tions should be clearly specified by the purchaser. II.B. B
39、uried Valves. Valves in this standard are provided with flanged ends. In buried applications, the purchaser is advised to consider providing means to accommodate issues such as differential settlement, capability to remove the valve or actuator for maintenance, access to the valve interior for inspection, support of the Copyright 2015 American Water Works Association. All Rights Reserved.
