1、Flowmeters in Water Supply Manual of Water Supply Practices M33 Third Edition Ideal crop marks Ideal crop marks 1P - 30033 4/18 www.awwa.org Dedicated to the worlds most important resource, AWWA sets the standard for water knowledge, management, and informed public policy. AWWA members provide solut
2、ions to improve public health, protect the environment, strengthen the economy, and enhance our quality of life. M33 T his manual provides information about the most common large flowmeters used in water treatment and in custody-transfer applications, including the Venturi, modified Venturi, orifice
3、 plate, electromagnetic (mag), turbine and propeller, transit-time ultrasonic, vortex, averaging Pitot, and averaging insertable electromagnetic (mag). The discussion of these meters covers basic theory, installation, maintenance, and advantages and disadvantages. General concepts applicable to flow
4、meters are also discussed, including flow characteristics, installation, and performance. The third edition of this manual contains significant updates that aim to provide more specific information on flowmeters. Additional information has been added on data signals, electronic communication informa
5、tion signal outputs, field testing, and more.M33 Flowmeters in Water Supply, Third EditionManual of Water Supply Practices Flowmeters in Water Supply Third Edition M33Manual of Water Supply Practices M33, Third Edition Flowmeters in Water Supply Copyright 1999, 2006, 2018 American Water Works Associ
6、ation 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 w
7、ritten permission of the publisher. Disclaimer The authors, contributors, editors, and publisher do not assume responsibility for the validity of the content or any consequences of their use. In no event will AWWA be liable for direct, indirect, special, incidental, or consequential damages arising
8、out of the use of information presented in this book. In particular, AWWA will not be responsible for any costs, including, but not limited to, those incurred as a result of lost revenue. In no event shall AWWAs liability exceed the amount paid for the purchase of this book. Managing Editor: Melissa
9、 Valentine Sr. Specialist, AWWA Manuals: Sue Bach Cover Design: Melanie Yamamoto Library of Congress Cataloging-in-Publication Data Names: Keilty, Michael J., author. | Gemin, Joseph J., author. | American Water Works Association, issuing body. Title: Flowmeters in water supply / by Michael J. Keilt
10、y and Joseph J. Gemin. Other titles: AWWA manual ; M33. Description: Third edition. | Denver, CO : American Water Works Association, 2018 | Series: M33 | Includes bibliographical references and index. Identifiers: LCCN 2018014552 | ISBN 9781625762801 Subjects: LCSH: Flow meters. | Water-supply-Measu
11、rement-Equipment and supplies. | Water current meters. | Waterworks. Classification: LCC TC177 .K45 2018 | DDC 681/.28-dc23 LC record available at https:/lccn.loc.gov/2018014552 Printed in the United States of America ISBN 978-1-62576-280-1 eISBN 978-1-61300-461-6 American Water Works Association 66
12、66 West Quincy Avenue Denver, CO 80235-3098 awwa.orgiii AWWA Manual M33 Contents List of Figures, v List of Tables, vii Foreword, ix Acknowledgments, xi Chapter 1 Characteristics of Flow. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 Fluid Parameters, 1 Measu
13、ring Velocity, 2 Types of Flow, 3 Flow Conditioning, 5 Meter Coefficient of Discharge, 6 Chapter 2 Types of Flowmeters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 Turbine and Propeller Flowmeters, 9 Orifice Plate Flowmeters, 11 Venturi Flowmeters, 13 Mo
14、dified Venturis, 16 Averaging Pitot Flowmeters, 17 Variable Area Flowmeters, 19 Magnetic Flowmeters, 21 Insertable Full-Profile Averaging Magnetic Flowmeters, 24 Transit-Time Ultrasonic Flowmeters, 26 Vortex Flowmeters, 28 Coriolis Flowmeters, 30 Chapter 3 Flowmeter Selection . . . . . . . . . . . .
15、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39 Selection Parameters, 39 Meter Selection Considerations, 42 Meter Selection Block Diagram, 44 Chapter 4 Installation and Performance Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47 Piping Configuration and Fl
16、ow Straighteners, 47 Fluid Condition, 48 Flowmeter Considerations, 49 Electrical Connections, 50 Chapter 5 Communications, Information, and Signal Outputs . . . . . . . . . . . . . . . . .51 Definitions, 52 Signal Methodologies, 53 Design and System Integration, 55iv AWWA Manual M33 FLOWMETERS IN WA
17、TER SUPPLY Chapter 6 Field Testing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59 In Situ Testing Methods, 59 Diagnostics and Verification, 65 Recalibration/Proving, 67 Bibliography, 69 Index, 71 AWWA Manuals, 75v AWWA Manual M33 Figures 1-1
18、Velocity profiles, 4 1-2 Distorted velocity profiles, 5 2-1 Turbine flowmeter (left) and propeller flowmeter (right), 10 2-2 Schematic of an orifice plate flowmeter, 12 2-3 Schematic of one type of Venturi meter, 14 2-4 Location of pressure ports in Venturi meter and flow tube, 16 2-5 Schematic of a
19、n averaging Pitot flowmeter insertion tube, 17 2-6 Variable area flowmeter, 19 2-7 Schematic of a magnetic flowmeter, 22 2-8 Schematic of an insertable averaging magnetic flowmeter, 24 2-9 Schematic of a transit-time ultrasonic flowmeter, 26 2-10 Schematic of a vortex flowmeter, 29 2-11 Coriolis eff
20、ect, 30 2-12 Spring mass system, 31 3-1 Flowmeter selection block diagram, 44 4-1 Typical flow straighteners, 49 6-1 Influent/effluent meter comparison, 61 6-2 Pitot test meter, 62 6-3 Traverse graph, 63 6-4 Transit-time flowmeter, 64 6-5 Doppler flowmeter, 65This page intentionally blank.vii AWWA M
21、anual M33 Tables 1-1 Methods of flow measurement, 3 2-1 Types of flowmeters for the water industry, 8 2-2 Representative characteristics of various types of flowmeters, 9 3-1 Selected flowmeter selection data, 45 6-1 Summary of in situ flowmeter testing methods, 60 6-2 Diagnostic parameters for vari
22、ous flowmeter types, 66This page intentionally blank.Foreword This manual provides information about the most common large flowmeters used in water treatment and in custody-transfer applications. Information on other meters can be obtained from AWWA Manual M6, Water MetersSelection, Installation, Te
23、sting, and Maintenance. The flowmeters discussed in this manual include the Venturi, modified Venturi, orifice plate, electromagnetic (mag), turbine and propeller, transit-time ultrasonic, vortex, averaging Pitot, and averaging insertable electromagnetic (mag). The discussion of these meters covers
24、basic theory, installation, maintenance, and advantages and disadvantages. General concepts applicable to flowmeters are also discussed, including flow characteristics, installation and performance issues, communications, information and signal outputs, and flowmeter selection. The manual can be use
25、d as a bridge to other literature on flowmeters, to prepare the reader for further investigations into instrumentation design and applications. The Bibliography lists excellent information sources. For additional information, the reader should acquire the relevant manuals from the meter manufacturer
26、s. These manuals contain comprehensive information on meter specifications, theory, sizing, handling, installation, power and wiring, operation, maintenance, troubleshooting, and parts. While this manual attempts to include recommended practice in the use of flowmeters, it is not intended as an AWWA
27、 standard. ix AWWA Manual M33This page intentionally blank.AcknowledgmentsThis edition of AWWA Manual M33 was developed by the Manual M33 Subcommittee of the AWWA Standards Committee on Rate-Type Flowmeters. The members of the subcommittee had the following personnel at the time of revision: Michael
28、 J. Keilty, Chair W. Ault, Kamstrup Water Metering LLC, Forest Park, Ill. S. Carpenter, San Diego County Water Authority, Escondido, Calif. G.H. De Jarlais, Badger Meter, Milwaukee, Wis. D. Faber, Faber & Associates, Columbus, Ind. J.J. Gemin, AECOM, Kitchener, Ont. P.A. Hayes, Mammoth Community Wat
29、er District, Mammoth Lakes, Calif. A.M. Horbovetz, M.E. Simpson Company Inc., Valparaiso, Ind. M.J. Keilty, Endress+Hauser Flowtec AG, Estes Park, Colo. M.D. Kyser, Professional Engineering Consultants P.A., Tulsa, Okla. G.G. Land, Master Meter Inc., Mansfield, Texas E.J. Melanson, EJM Automation, N
30、orfolk, Mass. J.A. Olson, Badger Meter, Milwaukee, Wis. J.F. Panek Jr., McCrometer Inc., Rowley, Iowa J.A. Reiss, Elster AMCO Water, LLC, Ocala, Fla. S.F. Sarrouh, T&M Associates, Columbus, Ohio J.L. Smith, Primary Flow Signal Inc., Cranston, R.I. J.S. Trofatter, JST Environmental, Land O Lakes, Fla
31、. S.Y. Tung, City of Houston, Houston, Texas D.C. Wyatt, Wyatt Engineering, Lincoln, R.I. This edition of the manual was reviewed and approved by the AWWA Standards Committee on Rate-Type Flowmeters. The members of the committee at the time this manual was approved included: Joseph J. Gemin, Chair G
32、eneral Interest Members J.A. Casados, Instituto Mexicano de Tecnologa del Agua, Progreso, Mor. A. Dabak, Texas Instruments, Dallas, Texas D. Faber, Faber & Associates, Columbus, Ind. J.J. Gemin, AECOM, Kitchener, Ont. A.M. Horbovetz, M.E. Simpson Company Inc., Valparaiso, Ind. F.S. Kurtz, *Standards
33、 Engineer Liaison, AWWA, Denver, Colo. M.D. Kyser, Professional Engineering Consultants P.A., Tulsa, Okla. * Liaison, nonvoting xi AWWA Manual M33xii AWWA Manual M33 FLOWMETERS IN WATER SUPPLY xii E.J. Melanson, EJM Automation, Norfolk, Mass. R.A. Richter, National Institute of Standards and Technol
34、ogy, Gaithersburg, Md. S.F. Sarrouh, T&M Associates, Columbus, Ohio S. Thakurdesai, *Texas Instruments, Dallas, Texas J.S. Trofatter, JST Environmental, Land O Lakes, Fla. Producer Members R.A. Barillas, *Badger Meter, Milwaukee, Wis. G.H. De Jarlais, Badger Meter, Milwaukee, Wis. M.J. Keilty, Endre
35、ss+Hauser Flowtec AG, Estes Park, Colo. J.F. Panek Jr., McCrometer Inc., Rowley, Iowa J.L. Smith, Primary Flow Signal Inc., Cranston, R.I. D.C. Wyatt, Wyatt Engineering, Lincoln, R.I. User Members S. Carpenter, San Diego County Water Authority, Escondido, Calif. W.F. Dunnill, Consolidated Utility Di
36、strict of Rutherford County, Murfreesboro, Tenn. P.A. Hayes, Mammoth Community Water District, Mammoth Lakes, Calif. A. Land, Dallas Water Utilities, Dallas, Texas S.U. Mills-Wright, Standards Council Liaison, Dallas Water Utilities, Dallas, Texas S.Y. Tung, City of Houston, Houston, Texas K. Whitak
37、er, *San Diego County Water Authority, San Diego, Calif. * Alternate Liaison, nonvoting1 AWWA MANUAL M33 Chapter 1 M33 Characteristics of Flow Flow is an important measurement made at treatment and distribution facilities, and flowmeters are used to measure this flow. Flowmeters measure product outp
38、ut of a plant, water distribution into a community, pacing of chemical feeds, and customer charges, to name just a few applications. Day-to-day operational decisions and long-term planning are based on measurements from flowmeters. To achieve proper flow measurement, the fluid must be homogeneous, w
39、ith evenly dispersed solids or gases, acting as a single- phase fluid with no relative motion among its components. The fluids of main concern in water treatment generally meet these conditions. FLUID PARAMETERS The parameters and properties of fluids important to flowmetering are as follows: Densit
40、y ()mass per unit volume. Density is important when mass transfer measurements are needed. It affects the nature of the flow and fluid behavior and is used to calculate many other fluid parameters. Electrical conductivityability of the fluid to conduct electricity. This condition is typically met in
41、 the water industry. Flow areaarea of unobstructed flow. Accuracy of cross-sectional area measurement plays a major role in flow measurement accuracy. For example, a 1/8-in. deviation in the diameter of a 12-in. pipe will cause a 2 percent change in area. This is important because of the probable ch
42、ange of flow area caused by corrosion and erosion with time. Pressureforce per unit area. Flow is driven by the difference in pressure. Some flowmeters use the pressure differential across an obstruction to measure flow. Pressure is a measure of the static component of the fluids energy.AWWA Manual
43、M33 2 FLOWMETERS IN WATER SUPPLY Temperature of the fluid Change in temperature affects fluid viscosity, density, and pressure, which may cause measurement errors if not properly compensated for electronically or by recalibration. Sonic conductivityability of the fluid to conduct sound. This conditi
44、on is typically met in the water industry. Sonic velocityspeed of sound through the fluid. Velocity (V)fluids speed of flow. V is the average velocity over the flow area. Viscosity ()fluids resistance to flow. Viscosity affects the nature of the flow and fluid behavior and is used to calculate many
45、other fluid parameters. It causes shear forces to be dominant at lower velocities. It causes a point of zero velocity at the pipes surface. MEASURING VELOCITY One of the most common methods to determine rate of flow is to measure the fluid velocity and compute flow by the continuity equation, most s
46、imply presented as Q = VA. In this equation, Q is the rate of flow, V is the average velocity over the flow area, and A is the area occupied by flow. For custody transfer and other uses, flowmeters totalize the flow by integrating the rate of flow versus time. Positive displacement and other volumet
47、ric-type custody-transfer meters count and totalize the number of volumes of water that pass. To date, fluid velocity is measured indirectly by quantifying its effect on an influenced parameter. Most meters are identified according to the physical parameter used to determine the velocity. One or mor
48、e transducers are needed to detect such effect of liquid movement. The transducer is a device that, by its inherent nature, transforms energy from one form to another. Its output changes when it is influenced by flow. The transducer, in turn, allows detection of a change in flow, therefore indirectl
49、y identifying the velocity of a liquid. Examples are turbine, magnetic, and transit-time ultrasonic flowmeters. In turbine meters, the flow impinging on the turbine vanes imparts energy to the turbine and causes it to rotate. The rotation speed is proportional to the flow velocity, enabling the user to arrive at a value of velocity by counting the number of rotations per unit of time. Flow is simply the volume of a moving fluid passing through a cross-sectional area per unit of time. To achieve a time rate of change of volume Q i
