Extraccion

CONTROL VALVE HANDBOOK

Third Edition

FISHER CONTROLS INTERNATIONAL, INC
Marshalltown, Iowa 50158 U.S.A. Cernay 68700 France Sao Paulo 05424 Brazil Singapore 128461

Copyright  1965, 1998, 1999, Reprinted in 1999 and 2001. Fisher Controls International, Inc. All Rights Reserved.

Fisher, ENVIRO-SEAL and FIELDVUE are marks owned by Fisher Controls International, Inc., a business ofEmerson Process Management. The Emerson logo is a trademark and service mark of Emerson Electric Co. All other marks are the property of their respective owners.

Printed in U.S.A.

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Preface to Third Edition

Control valves are an increasingly vital component of modern manufacturing around the world. Well–selected and maintained control valves increase efficiency, safety, profitability,and ecology. The Control Valve Handbook has been a primary reference for more than 30 years. This third edition is a complete revision and update that includes vital information on control valve performance and the latest technologies. D Chapter 1 offers an introduction to control valves including definitions for common control valve and instrumentation terminology. D Chapter 2 develops the vitaltopic of control valve performance. D Chapter 3 covers valve and actuator types. D Chapter 4 describes digital valve controllers, analog positioners, boosters, and other control valve accessories. D Chapter 5 is a comprehensive guide to selecting the best control valve for an application. D Chapter 6 covers the selection and use of special control valves. D Chapter 7 covers desuperheaters, steamconditioning valves, and turbine bypass systems. D Chapter 8 offers typical control valve installation and maintenance procedures. D Chapter 9 includes information on control valve standards and approval agencies throughout the world. D Chapter 10 offers useful tables of engineering reference data. D Chapter 11 includes piping reference data. D Chapter 12 is a handy resource for common conversions.The Control Valve Handbook is both a textbook and a reference on the strongest link in the control loop: the control valve and its accessories. This book includes extensive and proven knowledge from leading experts in the process control field including contributions from the ISA and the Crane Company.
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Table of Contents

Chapter 1. Introduction to Control Valves . . . . . . . . .. . . . . . . . . . . . . . . . . . . . 1 What Is A Control Valve? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Process Control Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Sliding-Stem Control Valve Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Rotary-Shaft Control ValveTerminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Control Valve Functions and Characteristics Terminology . . . . . . . . . . . . . 16 Other Process Control Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Chapter 2. Control Valve Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Process Variability . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dead Band . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Actuator-Positioner Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Valve Response Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Valve Type AndCharacterization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Valve Sizing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Economic Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....