Tai Lieu Chat Luong PROCESS PLANT EQUIPMENT PROCESS PLANT EQUIPMENT Operation, Control, and Reliability Edited by MICHAEL D HOLLOWAY CHIKEZIE NWAOHA OLIVER A ONYEWUENYI A JOHN WILEY & SONS, INC., PUBLICATION Cover photography: courtesy of Chikezie Nwaoha Copyright © 2012 by John Wiley & Sons All rights reserved Published by John Wiley & Sons, Inc., Hoboken, New Jersey Published simultaneously in Canada No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400, fax 978-750-4470, or on the web at www.copyright.com Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, 201-748-6011, fax 201-748-6008, or online at http://www.wiley.com/go/permission Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose No warranty may be created or extended by sales representatives or written sales materials The advice and strategies contained herein may not be suitable for your situation You should consult with a professional where appropriate Neither the publisher nor author shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages For general information on our other products and services or for technical support, please contact our Customer Care Department within the United States at 877-762-2974, outside the United States at 317-572-3993 or fax 317- 572–4002 Wiley also publishes its books in a variety of electronic formats Some content that appears in print may not be available in electronic formats For more information about Wiley products, visit our web site at www.wiley.com Library of Congress Cataloging-in-Publication Data: Process plant equipment : operation, control, and reliability / edited by Michael D Holloway, Chikezie Nwaoha, Oliver A Onyewuenyi p cm Includes index ISBN 978-1-118-02264-1 (cloth) Pumping machinery–Maintenance and repair Pipelines–Maintenance and repair Valves–Maintenance and repair Compressors–Maintenance and repair Storage tanks–Maintenance and repair Mixing machinery–Maintenance and repair Boilers–Maintenance and repair Filters and filtration I Holloway, Michael H., 1963– II Nwaoha, Chikezie, 1984– III Onyewuenyi, Oliver A., 1952– TJ900.P725 2012 621.8–dc23 2011028229 Printed in the United States of America 10 For the memory of Denton Ward student and friend CONTENTS Contributors xxiii Preface xxiv SECTION I PROCESS EQUIPMENT OPERATION Introduction Michael D Holloway Valves Ali Ahammad Shoukat Choudhury, Chikezie Nwaoha, and Sharad Vishwasrao 2.1 2.2 2.3 2.4 2.5 2.6 2.7 Types of Control Valves, 10 2.1.1 Linear-Motion Control Valves, 10 2.1.2 Rotary-Motion Control Valves, 11 2.1.3 Nonreturn Valves, 12 2.1.4 Relief Valves, 12 Control Valve Actuators, 12 2.2.1 Pneumatic Valve Actuators, 12 2.2.2 Electric Valve Actuators, 13 2.2.3 Hydraulic Valve Actuators, 13 Control Valve Sizing and Selection, 13 2.3.1 Selecting a Valve Type, 14 2.3.2 Sizing and Selection: Letting the Computer Do It All, 15 Common Problems of Control Valves, 15 2.4.1 Control Valve Cavitation, 15 2.4.2 Control Valve Leakage, 16 2.4.3 Control Valve Nonlinearities, 17 Diagnosing Control Valve Problems, 19 Control Valve Reliability and Selection, 20 Control Valve Maintenance, 22 2.7.1 Detecting Control Valve Stiction, 23 vii viii CONTENTS 2.8 Control Valve Troubleshooting, 24 References, 24 Pumps 27 Craig Redmond 3.1 3.2 3.3 3.4 3.5 Types of Pumps, 28 3.1.1 Positive-Displacement Pumps, 28 3.1.2 Dynamic Pumps, 30 Pump Applications, 34 3.2.1 Flooded Suction Applications, 34 3.2.2 Suction Lift Applications, 35 3.2.3 Staged Pumping, 35 3.2.4 Solids-Handling Applications, 36 Pump Sizing and Selection, 37 3.3.1 System Head Curve, 37 3.3.2 Pump Peformance Curves, 38 3.3.3 Actual Pump Sizing and Selection, 39 3.3.4 Net Positive Suction Head, 40 3.3.5 Net Positive Suction Head Available, 40 Pump Maintenance, 40 3.4.1 Bearing Lubrication, 41 3.4.2 Seal Maintenance, 41 3.4.3 Maintaining Performance, 43 3.4.4 Winterizing and Long-Term Storage, 43 3.4.5 Cold Temperature Installations, 43 Pump Troubleshooting, 44 Pipes 45 Shaohui Jia 4.1 4.2 4.3 4.4 4.5 4.6 4.7 Types of Pipes, 45 4.1.1 Seamless Pipe, 45 4.1.2 Welded Pipe, 45 Pipe Selection, 46 4.2.1 Pipe Strength, 46 4.2.2 Pipe Toughness, 46 4.2.3 Pipe Weldability, 48 4.2.4 Piping Material, 48 Pipeline Network Design and Optimization, 48 Pipeline Failure, 50 4.4.1 Pipe External Corrosion, 51 4.4.2 Pipe Internal Corrosion, 52 4.4.3 Stress Corrosion Cracking, 53 Pipeline Inspection and Leak Detection, 54 4.5.1 Pipeline Inspection, 54 4.5.2 Pipeline Inspection Tools, 55 4.5.3 Pipeline Leak Detection, 56 Pipe Maintenance, 58 4.6.1 Pipeline Coatings, 58 4.6.2 Pipeline Repair, 59 Pipe Troubleshooting, 60 References, 61 CONTENTS Cooling Towers 63 Zaki Yamani Zakaria and Chikezie Nwaoha 5.1 5.2 5.3 5.4 5.5 Cooling Tower Operation, 63 5.1.1 Cooling Tower Psychrometrics, 63 5.1.2 Principles of Cooling, 65 5.1.3 Heat Exchange, 67 5.1.4 Components of Cooling Towers, 67 Types of Cooling Towers, 69 5.2.1 Natural-Draft Cooling Towers, 69 5.2.2 Mechanical-Draft Cooling Towers, 72 Common Problems of Cooling Towers, 74 5.3.1 Scale Deposits, 74 5.3.2 Delignification of Wood, 74 5.3.3 Poor Pump Performance, 75 5.3.4 Poor Airflow, 75 5.3.5 Makeup Water, 75 5.3.6 Clogging of Distribution Nozzles, 75 Measuring Cooling Tower Performance, 75 5.4.1 Performance Assessment, 76 Cooling Tower Maintenance, 77 References, 79 Filters and Membranes Flora Tong and Chikezie Nwaoha 6.1 6.2 6.3 6.4 6.5 6.6 6.7 Types of Filters, 81 6.1.1 Gas Filters, 82 6.1.2 Liquid Filters, 83 Mechanisms of Filtration, 87 6.2.1 Depth Straining, 87 6.2.2 Surface Straining, 87 6.2.3 Depth Filtration, 87 6.2.4 Cake Filtration, 87 Filter Selection, 87 6.3.1 Chemical Compatibility, 87 6.3.2 Accurate Pore Size, 87 Particle-Size Measurement Techniques, 88 6.4.1 Image Analysis, 88 6.4.2 Direct Mechanical Measurement, 88 6.4.3 Ultrasonics, 88 6.4.4 Laser Scattering Technology, 88 Filter Location, 89 6.5.1 Pressure Line Filters, 89 6.5.2 Suction Line Filters, 89 6.5.3 Return Line Filters, 89 Membrane Filtration, 89 6.6.1 Ultrafiltration, 90 6.6.2 Microfiltration, 94 6.6.3 Reverse Osmosis, 95 6.6.4 Nanofiltration, 102 Filter Maintenance, 103 6.7.1 Preparation for Maintenance, 104 References, 104 81 ix x CONTENTS Sealing Devices 107 Matt Tones and Jim Drago 7.1 7.2 7.3 7.4 7.5 Gaskets, 107 7.1.1 Gasket Materials, 107 7.1.2 Gasket and Seal Construction, 113 7.1.3 Principles of Gasket Operation, 119 7.1.4 Gasket and Metal Seal Applications, 120 7.1.5 Gasket Selection, 123 Compression Packings, 125 7.2.1 Packing Materials, 126 7.2.2 Packing Construction, 128 7.2.3 Packing Selection, 129 7.2.4 Packing Installation, 130 Mechanical Seals, 131 7.3.1 Considerations for Using Mechanical Seals, 132 7.3.2 Types of Mechanical Seals, 134 7.3.3 Mechanical Seal Applications, 137 7.3.4 Environmental Controls, 140 7.3.5 Failure Analysis, 142 7.3.6 Troubleshooting Mechanical Seals, 144 Expansion Joints, 147 7.4.1 Joint Construction, 148 7.4.2 Principles of Joint Operation, 149 7.4.3 Joint Selection, 149 7.4.4 Industrial Use of Expansion Joints, 152 7.4.5 Joint Installation, 155 7.4.6 Joint Troubleshooting, 156 General Sealing Device Selection, 157 7.5.1 Product Selection, 157 7.5.2 Understanding the Forces, 157 7.5.3 STAMPS Criteria, 158 References, 161 Steam Traps Jacob E Uche and Chikezie Nwaoha 8.1 8.2 8.3 8.4 8.5 Steam Trap Operation, 163 Types of Steam Traps, 164 8.2.1 Thermodynamic Steam Traps, 164 8.2.2 Mechanical Steam Traps, 166 8.2.3 Thermostatic Steam Traps, 169 Steam Trap Installation, 172 8.3.1 Outlets of Steam-Using Equipment, 172 8.3.2 On Steam Lines, 172 Steam Trap Checking, 172 8.4.1 Sight Method, 173 8.4.2 Sound Method, 174 8.4.3 Temperature Method, 174 8.4.4 Fluid Conductivity Method, 174 Common Problems of Steam Traps, 175 8.5.1 Air Binding, 175 8.5.2 Dirt, 175 8.5.3 Improper Sizing, 175 163 CONTENTS 8.6 8.7 8.8 8.9 8.5.4 Steam Trap Leakage, 175 8.5.5 Steam Locking, 176 8.5.6 Water Hammer, 176 8.5.7 Erosion of Seat and Valve Sealing Faces, 176 8.5.8 Life Expectancy, 176 Steam Trap Selection, 176 Steam Trap Applications, 178 8.7.1 Protection Service, 178 8.7.2 Process Service, 178 8.7.3 Other Applications, 178 Steam Trap Sizing, 178 8.8.1 Basic Considerations, 179 Steam Trap Maintenance, 181 References, 181 Process Compressors 183 N Sitaram and Chikezie Nwaoha 9.1 9.2 9.3 9.4 9.5 9.6 10 Types of Compressors, 183 Continuous Compression Compressors, 184 9.2.1 Ejectors, 184 9.2.2 Dynamic, Rotodynamic, or Turbocompressors, 185 Intermittent Compression Compressors, 186 9.3.1 Positive-Displacement Compressors (Intermittent Flow), 186 9.3.2 Rotary Compressors (Continuous Flow), 187 Centrifugal Compressors, 189 9.4.1 Major Components of Centrifugal Compressors, 189 9.4.2 Thermodynamics of Centrifugal Compressors, 195 9.4.3 Energy Transfer in Centrifugal Compressors, 196 9.4.4 Slip in Centrifugal Impellers, 197 9.4.5 Losses and Efficiencies, 198 9.4.6 Performance, Stall, and Surge, 199 9.4.7 Drivers, 201 Reciprocating Piston Compressors, 202 9.5.1 Compressor Operation, 202 9.5.2 Thermodynamic Laws, 203 9.5.3 Compression Cycles, 203 9.5.4 Power Requirements, 204 9.5.5 Multistage Compression, 204 9.5.6 Cylinder Clearance and Volumetric Efficiency, 205 9.5.7 Valve Losses, 206 9.5.8 Major Components of Reciprocating Piston Compressors, 206 9.5.9 Drivers, 207 Compressor Troubleshooting, 209 References, 210 Further Reading, 211 Conveyors Okenna Obi-Njoku 10.1 10.2 Industrial Use of Conveyors, 213 Types of Conveyors, 214 10.2.1 Belt Conveyors, 214 10.2.2 Bucket Conveyors, 215 213 xi xii CONTENTS 10.3 10.4 10.5 10.6 11 10.2.3 Cart-on-Track Conveyors, 215 10.2.4 Chute Conveyors, 216 10.2.5 Gravity Wheel Conveyors, 216 10.2.6 Monorails, 216 10.2.7 Chain Conveyors, 216 10.2.8 Pneumatic Conveyors, 217 10.2.9 Roller Conveyors, 217 10.2.10 Screw Conveyors, 218 10.2.11 Slat Conveyors, 218 10.2.12 Sortation Conveyors, 219 10.2.13 Vane-Type Throwing Machines, 219 10.2.14 Tow Conveyors, 219 10.2.15 Trolley Conveyors, 219 10.2.16 Vertical Conveyors, 220 10.2.17 Vibrating Conveyors, 220 10.2.18 Troughed Belt Conveyors, 220 10.2.19 Magnetic Belt Conveyors, 220 10.2.20 Power-and-Free Conveyors, 220 Conveyor Selection, 221 Conveyor Safety, 221 Conveyor Maintenance, 222 Summary, 222 References, 223 Storage Tanks Marcello Ferrara and Chikezie Nwaoha 11.1 11.2 11.3 11.4 11.5 11.6 Types of Storage Tanks, 225 11.1.1 Aboveground Tanks, 225 11.1.2 Underground Tanks, 226 Storage Tank Classification, 227 11.2.1 Aboveground Tanks, 227 11.2.2 Underground Tanks, 227 Construction Materials, 227 11.3.1 Tank Materials, 227 11.3.2 Protective Coatings, 228 11.3.3 Insulation, 229 Common Problems of Storage Tanks, 229 11.4.1 Corrosion, 229 11.4.2 Vapor Losses, 230 11.4.3 Storage Tank Fires, 231 Storage Tank Maintenance, 233 11.5.1 Tank Blanketing, 233 11.5.2 Holiday Detection, 233 11.5.3 Tank Cleaning, 234 Tank Appurtenances, 241 11.6.1 Mixers, 241 11.6.2 Dikes, 241 11.6.3 Insulators, 241 11.6.4 Platforms and Ladders, 242 11.6.5 Gauging Devices, 242 11.6.6 Valves, 242 11.6.7 Manways, 243 11.6.8 Diffusers, 243 225 682 MIXERS Figure VII-2 Mixing simulation using VisiMix REFERENCE Figure VII-3 683 Impeller flow patterns, visualizations generated by VisiMix concentrations of reactants in chemical reactors, and so on The mathematical models and calculation methods used in the VisiMix software have been subject to experimental verification, and most models have been tested on industrial scale and used in engineering practice for many years With the application of mathematical models through computer simulation programs, it is possible to evaluate and select the most suitable mixing condition corresponding to the specific process requirement These mathematical models and methods of calculations form a single system which allows for performing a chain of consecutive steps of mathematical simulation shown schematically in Fig VII-1 VisiMix input consists of data on mixing equipment and properties of the media The program presents the data on the actual dynamic characteristics of mixing equipment, and a wide set of data on local flow velocities, intensities of turbulence, micro-mixing, etc., that are required for mathematical modeling of different unit operations Figure VII-2 explains the operating steps of the software, along with some results Figure VII-3 depicts the flow patterns generated by VisiMix for different type of impellers in an agitated vessel Advances in mixing technology have enabled mixer manufacturers to develop and improvise agitator designs customized for end user applications Moreover, the improvements and the technological advances in the mechanical, electrical, and electronic components, instrumentation and process control, have accelerated the development of mixing equipment that maximize mixing performance at lower energy consumption REFERENCE Braginsky L, Kokotov Y Review of the Main Mathematical Models Used in VisiMix , VisiMix Ltd, Har Hotzvim, Jerusalem, 2000 (http://visimix.com/PROF/Reviewof theMainMathematicalModels.pdf) GLOSSARY OF PROCESSING TERMS Garlock Sealing Technologies (A Garlock Family of Companies) Actuator: A device attached to a valve that moves the stem, usually by means of a motor or pneumatics A valve fitted with an actuator is usually referred to as a control valve Adhesion: The clinging, binding, or sticking of two material surfaces to one another, such as rubber to rubber, rubber to metal, or rubber to cloth It also refers to the bond strength between two surfaces Ambient temperature: The temperature of the surrounding environment Anchor: The terminal point or fixed point from which directional movement occurs Angle: An L-shaped steel member used either as a duct flange or as the fastening connection of an expansion joint Angles are also used for bolting the joint to the mating flange surfaces of the ductwork or adjacent equipment Angular movement: Movement that occurs when one flange of the expansion joint is moved to an outof-parallel position vis-`a-vis the other flange Angular movement is measured in degrees ANSI: Acronym for “American National Standards Institute.” Antiextrusion ring: A ring of packing used at one or both ends of a packing set to prevent extrusion of the packing into clearances Also called a bull ring See also End ring and Junk ring API: Acronym for “American Petroleum Institute.” ASME: Acronym for “American Society of Mechanical Engineers.” Assembled spring inside diameter: The inner diameter of the garter spring, with the ends securely joined ASTM: Acronym for “American Society for Testing and Materials.” Baffle/flow liner: A metal shield that is designed to protect an expansion joint from the abrasive particles in a gas stream and to reduce flutter caused by air turbulence in a gas stream Baffles and flow liners may be welded or bolted into position Bellows: That portion of an expansion joint which accommodates movement of the joint convoluted or flat Belt-type expansion joint: An expansion joint in which the flexible bellows portion of the joint is made flat and bolted or clamped to metal adapter flanges or frames Blocking agent: A coating applied to braided packing to fill the area between fibers, blocking the passage of a medium through the body of the braid, improving its sealing characteristics This may be a grease, an oil, or a PTFE dispersion Burst: A rupture caused by internal pressure Bushing: A metallic or carbon ring used to take up excess space in a stuffing box Butt cut: A straight cut at the seam (or joint) of a packing ring Case OD Sealer: A coating applied to the outside diameter of a seal’s case to prevent leakage between the case and the housing bore Cavitation: An undesirable phenomenon that sometimes occurs in pumps, in which small vapor bubbles are created in the area of the impeller As the vapor bubbles move along the vanes of the impeller to an area of higher pressure, they rapidly collapse This collapse or “implosion” is so rapid that it may be heard as a rumbling noise or felt as vibration The forces generated Process Plant Equipment: Operation, Control, and Reliability, First Edition Edited by Michael D Holloway, Chikezie Nwaoha, and Oliver A Onyewuenyi © 2012 John Wiley & Sons, Inc Published 2012 by John Wiley & Sons, Inc 685 686 GLOSSARY OF PROCESSING TERMS as a result of cavitation may damage the impeller or even the packing set Centering ring (or guide ring): A solid piece of metal used on the outside diameter of a gasket winding to center the gasket properly on the sealing surface by locating the ring against the studs in the connection The ring also acts as a compression limiter to prevent overcompression of the winding Centrifugal pump: A type of pump that relies on the rotation of an impeller to generate pressure and cause flow Checking: The short, shallow cracks on the surface of a rubber product resulting from damaging action or environmental conditions Chevron® Packing: Also known as V or vee packing and stack packing, an automatic hydraulic and pneumatic seal designed for sealing rods, rams, pistons, and plungers Consisting of a male and female adapter and at least three chevron “vee” rings, which utilize a distinct hinge area to allow automatic reaction to pressure Chevron-type packing seals are lip-type seals that are gland sensitive Cold flow: Permanent and continual deformation of a material that occurs as a result of prolonged compression or extension at or near room temperature Compressed height: The height of a packing ring or packing set after it has been compressed in a stuffing box Compressed sheet: A gasketing material containing primarily fibers, rubber, and fillers, manufactured on a special calender (known as a sheeter) in such a manner that the compound is caused to build up under high load as an oriented sheet on one roll of the sheeter Compressibility: The quality or state of being compressible In the case of gasketing, it is the percentage loss of thickness when subject to a given load Compression limiter: A ring used in conjunction with a seal to control or limit compression of the seal Compression packing: A deformable material used to prevent or control the passage of a pressurized fluid between surfaces that move in relation to each other Compression set: The deformation that remains in the gasketing after it has been subjected to, and released from, a specific compressive stress for a definite period of time at a prescribed temperature (Compression set measurements are for the purpose of evaluating the creep and stress relaxation properties of elastomeric constructions.) Compressive stress: The Force per unit area compressing (squeezing) the seal Cross section: (1) The view of a part as if it were cut to show its internal structure (2) The distance between the shaft or stem surface and the bore of a stuffing box See also Packing space (3) The shape of a packing ring at a cut A packing ring may have a square, rectangular, or round cross section Cryogenic: Of or relating to a very low temperature Cup and cone: The shape of certain types of die-formed ring sets In a cup and cone set, the rings have conical surfaces that nest into one another Cup packing: A specific type of hydraulic or pneumatic sealing element that seals primarily on its outside diameter Cure: The act of vulcanization See also Vulcanization Cut-ring set: A braided material cut into individual rings for a specific stem or stuffing box size and packaged as a set Cycle and adjust procedure: A procedure used to consolidate a packing set after it has been installed in a stuffing box This procedure helps to reduce the amount of gland load relaxation that occurs after a valve has been put into service Deformation: A stress-induced change of form or shape Density: The ratio of the mass of a body to its volume, expressed as lb/ft3 or g/cm3 It is common for dieformed graphite foil rings to be produced to a specific density Design pressure or vacuum: The pressure or vacuum condition that exists during system startup and/or shutdown operations During this cyclic phase in the system, both pressure and vacuum conditions may occur Design temperature: The maximum or most severe temperature expected during normal operation caused by equipment failure See also Excursion temperature Discharge pressure: The fluid pressure measured on the discharge (or outlet) side of the pump, where the fluid exits the volute Ductility: The ability to be drawn Example: The stretching of metal wire to a smaller cross section Eccentricity: The distance that the central axis of a shaft is offset from the center of the stuffing box through which it passes Elastic limit: The limiting extent to which a body may be deformed and yet return to its initial shape after removal of the deforming force Elastomer: An elastic rubber-like material which, in the vulcanized state and at room temperature, can be stretched repeatedly to at least twice its original length Upon release of the stress, this material will return immediately to approximately its original length Elongation: The increase in length expressed numerically as a fraction or percentage of the initial length GLOSSARY OF PROCESSING TERMS Emissions: Gaseous or liquid leakage given off by a piece of equipment This usually refers to volatile organic hydrocarbons monitored by government agencies It is typically expressed in parts per million volumetric (ppmv, or simply ppm) End ring: A ring used at the top or bottom of a packing set, usually functioning as a wiper ring and/or an antiextrusion ring See also Antiextrusion ring, Junk ring, and Wiper ring EPA: Acronym for “Environmental Protection Agency,” the U.S government agency responsible for protecting the public’s health and the environment by developing and enforcing regulations and studying environmental issues Excurision temperature: The temperature the system could reach during an equipment failure such as an air heater failure Excursion temperature should be defined by maximum temperatures and time duration of excursion Expansion: The increase in any linear dimension or volume External pressure: The pressure (lb/in2 ) exerted on the outside diameter of a seal Extrusion: The distortion, under pressure, of a portion of a seal into the clearances between mating metal parts Gasket: A deformable material which when clamped between essentially stationary faces prevents the passage of matter through an opening or joint Gasket spacer: A gasket material cut to fit in a stuffing box between braided packing rings Gasket spacers may be used to provide protection against abrasive particles, to increase the pressure resistance of some packing sets, or to reduce the flow of fluid through the body of the braid Gasketing: Material in bulk form from which gaskets may be cut Gauge: The thickness of a material; also the device used to measure material thickness Gland: See Packing gland Gland follower: A part that protrudes into a stuffing box to compress a packing set or packing ring Gland load: The amount of load applied to a packing set This may be expressed in terms of force (lb, N) or in terms of pressure (psi, kPa) Gland pressure: The amount of pressure applied to a compression packing set by the gland follower, usually expressed in psi or kPa Gland stud: A threaded rod or eye bolt extending from a valve or pump body that is used to compress a packing set 687 Hand wheel: A wheel located at the top of a manually operated valve that is used to actuate the valve stem Hat (flange) packing: An old form of sealing rod which seals on the inside diameter only Head: The pressure at any point in a fluid can be thought of as being caused by a vertical column of the liquid that, due to its weight, exerts pressure at the point in question The height of this column is called the static head (or sometimes simply head ) and is expressed in terms of feet or meters of liquid Heat exchanger: A piece of equipment designed to transfer thermal energy from one medium to another The unit is typically a long cylindrical body with multiple tubes passing within the body A medium at one temperature flows within the body but external to the tubes, while a medium of another temperature flows within the tubes, thus allowing thermal energy to be exchanged without cross-contamination of the products Helical motion: The circular, screw-like, up and/or down motion of a rod or valve stem Homogeneous: Of uniform composition throughout Hydrodynamic seal: A dynamic sealing device that utilizes the viscous shear and inertia forces of the fluid, imparted by a helically grooved or ribbed seal lip, to generate a pressure differential that opposes fluid flow ID: Acronym for “inside diameter.” Used when denoting the inside dimension of a packing set, usually equal to the stem or shaft diameter Impeller: The part of a centrifugal pump that when rotated will generate pressure and cause flow Inclusion: Foreign matter included in seal material Inner ring: A solid ring used on the inside diameter of a spiral wound gasket in higher-pressure applications This ring also acts as a compression limiter and provides protection from the media stream Inside face: That surface of the inner case which faces, and is usually in contact with, the fluid being sealed Internal pressure: The pressure (lb/in2 ) exerted on the inside diameter of a seal ISO: Acronym for “International Standards Organization.” Jacketed gasket: Type of gasket with a metallic cover either partially or completely surrounding a filler material to improve temperature, pressure, chemical, and crush resistance Joint: An interstice (crevice) between rigid members of a fluid container Leakage: An escape of gases or liquids from a piece of equipment Leakage rate: The quantity of fluid passing through (or around) a seal in a given period of time 688 GLOSSARY OF PROCESSING TERMS Lip diameter: The inner diameter of a seal lip, measured with the spring installed Lip force: The radial force exerted by an extension spring and/or lip of a seal on the mating shaft Lip force is expressed as force per unit of shaft circumference Lip height: The axial distance from the outside seal face to the toe face Lubricant starvation: Lack of proper lubrication at the seal interface, which may cause premature wear and early failure Lubrication: The use of a liquid or fluid to reduce the friction, heat, or wear between two surfaces where movement is taking place M factor: Gasket property The factor that provides additional preload capability in the flange fasteners to maintain sealing pressure on a gasket after the internal pressure is applied to the joint Used in conjunction with the Y factor to perform flange design Medium: The fluid that is being sealed Metal C-ring: A C-section metal seal with low-load characteristics Plating and coating are added for improved performance Metal O-ring: A hollow tubular seal with a circular cross section Various shapes and sizes can be fabricated and different plating and coating can be added for better performance Metal seal: A seal composed entirely of metal components which when compressed between two stationary faces prevents the passage of a particular media through a specified space or opening Misalignment: The out-of-line condition that exists between the adjacent face of equipment or system flanges MOV: Acronym for “motor-operated valve,” a motoractuated control valve Movements: The dimensional changes that an expansion joint is required to absorb, such as those resulting from thermal expansion or contraction MRO: Acronym for “maintenance and repair organization.” MSS: Acronym for “Manufacturers Standardization Society” of the valves and fittings industry MTI: Acronym for “Material Technology Institute” of the chemical process industry Nonmetallic expansion joint: An expansion joint that utilizes flexible nonmetallic material to accommodate joint movements O-ring: An elastomeric seal of homogeneous composition molded in one piece to the configuration of a torus, with circular cross section; more simply, a round ring with a round cross section OD: Acronym for “outside diameter,” used to denote the outside dimension of a packing set (usually equal to the stuffing box bore) Oil seal: A seal designed primarily for the retention of oil Oil swell: The change in volume of a gasketing product resulting from contact with oil Omnidirectional strength: Strength in all directions Operating pressure/vacuum: The temperature at which a system generally will operate during normal conditions Outer case: The outer thin-wall rigid structure of a lip-seal assembly, which contains the inner case, the primaryseal ring, the spring parts, and the secondary seal Packing gland: The space into which a compression packing is inserted Also known as a stuffing box Packing groove: A groove machined into a flange or joint to accommodate a packing ring Packing hook: A tool similar to a corkscrew for removing packing from a stuffing box Packing space: The distance between the shaft or stem surface and the bore of a stuffing box Packing space (x ) can be calculated by the following equation: x = (OD−ID)/2 Permanent set: The degree to which an elastic material fails to return to its initial form after deformation Permeability: The quality or condition of allowing passage of fluid, gases, or air through a material such as rubber pH: The measure of the strength of an acid or base On the pH scale, a neutral solution (neither acidic or basic) has a pH of Solutions with a pH below are acidic; the smaller the pH value, the more acidic the solution Solutions with a pH above are basic Piston: A cylindrically shaped part that fits within a cylinder and transmits or receives motion by means of a connecting rod (a cylinder rod) Pitting: Surface cavities that occur on a metal as a result of galvanic corrosion or mechanical erosion Plunger: A cylindrically shaped part that has a uniform diameter and is used to transmit thrust (as in a hydraulic cylinder) or develop pressure and cause flow (as in a reciprocating pump) Pneumatic seal: An extruded or molded elastomeric seal designed to expand and retract to provide a secure, reliable seal that can hold, position, or handle objects in a wide range of applications Precompression: Compression of the expansion joint during installation so that in the cold position the joint has a given amount of compression in addition to the rated amount of compression The purpose of precompression is to allow for unexpected or additional axial extension GLOSSARY OF PROCESSING TERMS Pressure: Force per unit area, usually expressed in pounds per square inch (psi) or kilograms per square centimeter (kg/cm2 ) Pressure cycling: The variation of pressure in a system Pressure, absolute (PSIA): The pressure above zero absolute: the sum of atmospheric and gage pressure Pressure, atmospheric: The pressure exerted by the atmosphere at any specific location Sea level pressure is approximately 14.7 lb/in2 absolute Pressure, gauge (PSIG): The pressure differential above or below atmospheric pressure, expressed as lb/in2 or psig Primary lip: The normally flexible elastomeric component of a lip seal assembly, which rides against the rotating surface and affects the seal Protective cover: Outer cover material used to protect boot material during shipment and installation psi: Abbreviation for “pounds per square inch,” a unit of pressure PTFE: Acronym for “poly(tetrafluoroethylene),” a polymer having excellent chemical resistance PTFE dispersion is used as a coating for many styles of packing Some packing styles are constructed of PTFE fibers Teflon® is DuPont’s trade name for their PTFE materials Pump shaft: The metal rod connecting the impeller of a pump to the motor Purge fluid: A clean liquid (usually, water) which is injected through a flush port to flush solid particles from the stuffing box area to minimize abrasive wear Purge port: A hole in the side of a stuffing box through which a flushing fluid is injected Quarter-turn valve: A valve that will fully open or close with a 90◦ rotation of the stem Radial: In the direction perpendicular to a shaft axis Radial expansion: The ability of a packing material to spread out in the radial direction of a stuffing box when it is compressed Radial lip seal: A type of seal that features a flexible sealing member referred to as a lip The lip is usually of an elastomeric material It exerts radial sealing pressure on a mating shaft in order to retain fluids and/or exclude foreign matter Radial load: The total force (load) acting on a seal lip which tends to maintain contact of the lip on the shaft It is the sum of the forces developed from seal interference and the garter spring Reciprocating: The motion of a shaft back and forth in the direction of its axis Reciprocating motion: An oscillating, back-and-forth motion as it normally pertains to a piston rod or valve stem 689 Reciprocating pump: A type of pump that relies on the reciprocating motion of a plunger, or series of plungers, to generate pressure and cause flow Recovery: The degree to which a product returns to its normal dimensions or shape after being distorted Recovery (gasketing): The increase in thickness of a gasket after a load is removed Remote handling: Handling without direct individual contact, usually done with robotic arms Resilience: The ratio of energy given up by the elastomer upon releasing it from a definite deformation to the energy required to produce the deformation Unless the deforming is momentary, the result obtained will be complicated by the partially plastic nature of the elastomer Retaining rings: Segmented metal rings installed directly against the back of the expansion joint flange and bolted through to the metal flange of the pipe Rising stem valve: A valve in which the movement of the stem is simply reciprocating, with no rotation Rising/rotating stem valve: A valve in which the movement of the stem is both reciprocating and rotating at the same time, usually following a helical path Rod: The metal shaft that extends from the piston to outside the cylinder Roll: Sheet rubber and gasketing material of a uniform width rolled up on itself from which gaskets and other products of various shapes may be cut Rotary: The motion of a body turning on an axis Rotary service: A dynamic type of sealing application in which one member remains stationary while the other moves past it in a rotating mode This type of service generally involves a continuous motion between members and higher surface speeds than those encountered in reciprocating applications The generally higher degree of frictional heating, combined with the fact it is concentrated in one area, sometimes leads to heat-related seal problems Rotation (flange): The warping, bowing, or bending of a flange that can occur from too much bolt load Rough trim: A trimmed surface with irregularities on the outside and inside lip surfaces in the immediate vicinity of the contact line Roughness: Irregularities in shaft surface texture that result from the production process See SAE J448a, (June, 1963) for more information rpm: Abbreviation for “revolutions per minute,” a measurement of the rotary speed of a rotating shaft Runout: A measurement of how far a shaft moves in the radial direction 690 GLOSSARY OF PROCESSING TERMS Scoring: Gouges on the surface of a shaft, stem, or bore due to mechanical wear Scratch: A shallow discontinuity in seal material whereby no material is removed Seal: Any device designed to prevent or control the movement of fluid from one chamber to another to exclude contaminants Seal assembly: A group of parts, including sealing surfaces, provisions for initial loading, and a secondary sealing mechanism, which accommodates the radial movement necessary for installation and operation Seal cage: See Lantern ring Seal case: A rigid member to which the seal lip is attached Seal gasket: A gasket that is placed between two adjacent metal parts to make a gastight connection Seal outer diameter: The external diameter of a lipseal assembly, which normally corresponds to the outer diameter of the outer seal case Seal solution: Any gasket or seal, which when properly installed prevents the escape of matter Sealability: The measure of fluid leakage both through and across both faces of a gasket Measured either by using ASTM F-37 or DIN 3535 equipment and procedures Seating load: The load required to compress a seal properly This will vary depending on the size and shape of the seal (This does not include operating hydro end forces.) Self-energizing O-ring: An O-ring with a hole drilled on the pressure side, allowing pressure to equalize inside the O-ring; prevents collapse of the ring Setback (stand of height): The distance the expansion joint is set back from a gas stream to allow for lateral movements and to prevent the joint from protruding into the stream or rubbing on the baffle when operating under negative pressure Setback also reduces the heat input and prevents abrasion from solids or particles in the stream Shaft: The metal rod connecting the impeller of a pump to the motor Shaft eccentricity: The radial distance that the geometric center of a shaft is displaced from the axis of shaft rotation Shaft lead: Spiral grooves on a shaft surface caused by relative axial movement of grinding wheel to shaft Shaft runout: See Dynamic runout Shaft surface finish: See Shaft surface texture Shaft surface texture: A term used to describe the quality, appearance, or characteristics of the shaft surface resulting from such operations as grinding, polishing, and burnishing See SAE J448a (June 1963) for additional information Sheeter: A special calender used to make compressed sheet Shipping straps or bars: Braces that are located between the two expansion joint flanges to prevent overcompression or distortion during shipment and joint assembly Single-end coating: The process of applying a coating to the individual yarns (or “ends”) of a packing before they are braided This process results in a very thorough uniform coating throughout the braid Size, actual: Actual dimensions of a part, including tolerance limits Size, nominal: The approximate size of a part in fractional dimensions Skim coat: A layer of rubber laid on a fabric but not forced into the weave Normally laid on frictioned fabric Slab: A thick sheet Sleeve: A metal cylinder that is placed over a pump shaft in the sealing area In pumping applications, certain media and packing materials can cause abrasive wear on the rotating surface A sleeve is a relatively inexpensive, replaceable component that protects the pump shaft from wear Slip stick: A friction-related phenomenon in which the sealing element tends to adhere and rotate with the shaft surface momentarily until the elastic characteristics of the sealing element overcome the adhesive force, causing the seal lip to lose sufficient connection with the rotating shaft long to allow leakage This cycle repeats itself continuously and is normally associated with nonlubricated and boundary-lubricated conditions Slurry: A fluid mixed with solid particles In packing applications handling slurries, abrasion is a major concern Steps must be taken to minimize abrasive wear of the packing materials Specific contact pressure: Seating load divided by seal contact area Specific gravity: The ratio of the weight of a given substance to the weight of an equal volume of water at a specified temperature Spiral trim: A trimmed surface that has a spiral pattern Splicing: A procedure for making an endless boot or bellows from open-ended material Splicing may be accomplished by one or more of the following: cementing, bonding, heat sealing, stitching, vulcanizing, or mechanical fasteners Spool packing: Packing material that is braided and sold on a spool, as opposed to cut-ring sets or die-formed ring sets Spring groove: A depression formed in the head section of a seal It is generally semicircular in form and serves to accommodate and locate the garter spring GLOSSARY OF PROCESSING TERMS Spring outside coil diameter: The outer diameter of an individual helical coil of a garter spring Spring rate: The force in pounds required to deflect an expansion joint in in compression and elongation or in a lateral direction Spring retaining lip: The portion of the primary lip that restricts the axial movement of the extension spring from a predetermined position Spring witness marks: A series of indentations or depressions remaining in the spring groove of a radial lip seal after the spring has been removed or dislocated Square braid: A type of braiding construction that yields a soft, flexible packing material having a square cross section Also referred to as regular braid Squeeze seal: Also known as installation activated , a squeeze seal relies on the squeeze or compression it achieves at installation to create a seal The squeeze or compression is due to its high degree of interference This type of seal generally seals well at low pressure; however, in dynamic applications, it is characterized by a high wear rate and friction Stack height: (1) The combined height of all the rings of a packing set (2) The combined height of all the components in a stack of Belleville washers used to liveload a packing set Static seal: A seal whose sealing surface sees no motion—the opposite of dynamic seal Stem: The meral rod that connects the internal components of a valve to a handwheel, handle, or actuator Stock: In the papermaking industry, the wet pulp mixture at any point in the papermaking process Strain: The unit change, due to force (stress), in the size or shape of a body compared to its original size or shape—it is a nondimensional quantity but is frequently expressed in inches per inch, centimeters per centimeter, and so on Stress: The force applied to a unit area.(lb/sq in.) Stress relaxation: The loss of an initial bolt load or bolt stress, often accelerated by thermal cycling Stress–strain: The relationship of load and deformation in a body under stress In rubber this is most commonly the relationship of tension (stress) and elongation (strain) Strong oxidizer: In packing applications, strong oxidizers cause the degradation of organic packing materials such as carbon, graphite, and cellulosic fibers PTFE packing materials are generally used in these applications, due to their oxidation resistance Stuffing box: The space into which compression packing is inserted Also known as a packing gland 691 Suction pressure: The fluid pressure measured on the suction (or inlet) side of the pump where the fluid enters the volute Surface finish: A measure of the roughness of a surface, usually expressed in microinches or micrometers Surface speed: The linear speed of a point on the surface of a rotating shaft, usually expressed in ft/min or m/s Surge pressure: Operating pressure plus the increment above operating pressure that the expansion joint will be subjected to for a very short time period Surge pressure is typically due to pump starts, valve closing, and the like Swelling: The increase in volume or linear dimension of a specimen immersed in liquid or exposed to a vapor Symmetrical seal: A seal that has the same shape on either side of its centerline Tacky (rubber surface): Sticky material that will adhere to itself, usually to ply up layers Tensile strength: The amount of tensile stress that causes a specimen to rupture; measured in psi Thermal barrier: A layer of insulating material designed to reduce the surface temperature at the gas sealing layer to a level compatible with its heat resistance capability Thermal conductivity: The ability of a material to transmit heat A measure of the rate at which thermal energy is transferred through a substance High thermal conductivity is an advantage in pump packing applications, where it is important to transfer frictional heat away from the shaft–packing interface so that the packing does not burn Thermal cycling: The repeated heating and cooling of a tank, vessel, or piping system The duration of the cycle can vary tremendously Thermal expansion: The increase in volume or length of a material that occurs as a result of a temperature increase Thermal movements: Movements created within a system caused by a thermal change Can be axial, lateral, or torsional Tolerance: The upper and lower limits between which a dimension must be held Torque: Informal definition: A measure of “twisting force.” In packing applications, one might be concerned with the torque applied to the gland stud nut or the torque required to overcome friction between the packing and the valve stem Torsional rotation: The twisting of one end of an expansion joint with respect to the other end about its longitudinal axis, Such movement being measured in degrees, as is angular rotation 692 GLOSSARY OF PROCESSING TERMS Trim: The removal of superflous parts from a molded product, usually removal of parting-line flash or feed sprues Trim cut: Damage to the elastomeric portion of a seal during trimming Tube: The inner ply of the expansion joint that is in direct contact with the system medium U-seals: A packing in which the element has a U-shaped cross section Ultimate elongation: The maximum elongation prior to rupture Unbonded flash: Flash that does not adhere properly to the mating material to which it is intended to be bonded Uncompressed height: The height of a packing set or packing ring before being compressed in the stuffing box Unirotational seal: A seal designed for applications having a single direction of shaft rotation Unitized seal: A seal assembly in which all components necessary for accomplishing the complete sealing function are retained in a single package Vacuum: Negative pressure; when a gasket or seal is used to prevent the passage of external media or air into a system Valve body: The part of a two-piece valve that houses the internal workings of the valve The flanges that attach the valve to a pipeline are also part of the body Valve bonnet: The part of a two-piece valve that attaches to the valve body It houses the stuffing box and provides support to guide the valve stem Valve stem: See Stem Vibration: The ability of a flexible connector to absorb mechanical oscillations in a system Viscosity: A manifestation of internal friction opposed to mobility The property of fluids and plastic solids by which they resist an instantaneous change of shape (e.g., resistance to flow) Volume swell: An increase in physical size caused by the swelling action of a liquid Volute: The internal area (housing) of a centrifugal pump where the fluid comes in contact with the impeller Wear sleeve: A replaceable metal ring generally used in assemblies to eliminate expensive shaft replacement caused by grooving that may occur at the seal–shaft interface Weathering: The surface deterioration of a rubber article during outdoor exposure, such as cracking, crazing, or chalking Weepage: A minute amount of liquid leakage by a seal Weld in baffle: A baffle that is designed to be welded to the duct wall This design can be of either single- or double-acting type Welding blanket: A fire-resistant blanket that is placed over an expansion joint to protect it from weld splatter during a field welding operation Whip: Deflection of a shaft (usually, on a mixer or pump) due to a rotating mechanical load A long shaft that is not supported by bearings is more susceptible to whip than is a short shaft or one that is supported by bearings Wicking: Leakage through a gasket, not around it Wiper ring: A ring of braided packing used in conjunction with graphite foil rings to wipe a reciprocating valve stem clean of graphite particles and keep the graphite contained in the stuffing box Wire-reinforced: A product containing wire(s) to give added strength, increased dimensional stability, or crush resistance Work pressure: The maximum operating pressure encountered during normal service Y Factor: Gasket property The minimum design seating stress in either psi or megapascal over the contacted area of a particular gasket The stress required to provide a sealed joint with a 2-psig (virtually psig) internal pressure in the joint Used in conjunction with the M factor to perform flange design Yield strength: The amount of stress that causes a material to lose its elasticity permanently INDEX Abrasive wear, 441, 423 Accumulation, Accuracy, 656, 670 Action, 624 Action-at-a-distance force, 417 Acute toxic effects, 491 Adhesive wear, 422 Adsorption, 429 Aeration, 318, 319 Agitators, 123 Air compressor, 659 Air lines, 661 Air quality, 659 Alarms, 653 Allowable stress, 448 American Petroleum Institute, 436 Amines, 325 Ammonia, 442 plant, 537 Anchor, 683 Applied force, 417 Arc strike, 440 Atomizer, 320 Autoignition temperature, 494 Automatic mode, 625 Babbitt bearings, 423 Backfire, 321 Backwash (BW), 91 Baffle, 682 Batch processes, 544 Blowdown, 317, 322 Boilers, 6, 297–327 Bolts, 159 braid, 128 grade, 159 multitrack, 128 round, 128 square, 128 Braided tape, 128 Braid-over-braid, 128 Braid-over-core, 128 Breakdown, 33, 35, 37 Brittle fracture, 421 Buckling, 468, 475, 477 Bulk load, 4, 27 Bulk material handling, Burners, 326, 327 Burst checks, 665 Burst disks, 665 Burst pressure, 666 Calorific, 325 Carboxyhemoglobin, 492 Carcinogenic materials, 490–492 Carcinogenicity, 515 criteria, 515 Carryover, 308, 318 Cascade control, 629 guidelines, 630 illustrated, 630 issues, 630 modes, 631 structure, 630 tuning, 632 Case style, 670 Caustic, 442 Cavitation, 143 Chain polymerization, 427 Check list, 528, 559, 570 Chelate, 317 Chemical compatibility, 670 Chemically enhanced backwash (CEB), 91 Chlorination, 318 Chronic toxic effects, 492 Clarification, 318 Clean in place (CIP), 91 Closed loop method, 628 Coagulation, 318 Cohen–Coon method, 628 Combustion, 398, 303–304, 319 Compressed Gas Association (CGA), 663 Compressor, 660 Compressor sealant, 661 Concentration, 428 Conceptual framework, 506, 510 Condition monitoring, 414, 436 consequences, 530 Connection size, 670 Contact force, 417 Contaminant type, 428 Continuous processes, 544, 547 Control algorithm, 619 Control modes, 625 Controllability, 629 Controllable variables, 506, 619 Controller, 321 Conveyors, Cooling towers, cork, 117 water, 659 Corrosion, 307, 425, 636, 670 barrier, 677 chloride stress, 138, 675 CO2 , 674 crevice, 441, 676 due to oxygen, 675 elemental sulphur, 675 erosion, 676 galvanic, 676 hydrogen sulphide, 675 Process Plant Equipment: Operation, Control, and Reliability, First Edition Edited by Michael D Holloway, Chikezie Nwaoha, and Oliver A Onyewuenyi © 2012 John Wiley & Sons, Inc Published 2012 by John Wiley & Sons, Inc 693 694 INDEX Corrosion (Continued ) methods to combat, 467 microbial, 676 monitoring, 438, 679 morphology, 673 in nonmetals, 425 Corrosive media, 677 Corrosive process, 490 Corrosive wear, 423 Crack monitoring, 438 Creep, 419, 468, 470, 479 Creep damage 447 Creep deformation, 419 Crevice corrosion, 441 Critical expose temperature, 452 Current controls, 415 Daldt, 461 Damage minimizing system, 541 Dampener, 321 Dead time, 621, 623 Dearation, 318 Decision mechanism, 509, 510 Decision system, 503, 579 Decision tree, 509 Deflection, 468, 482 Deformation, 468, 479, 484 Degree of reaction, 429 Deionization, 318 Deposit formation, 426 Derivative response, 624 Design and control safety, 563 Design measure, 517 Design safety checklist, 500, 502, 532 codes, 467–469, 478, 485 design, 467–471, 473–475, 477–483 pressure, 474, 475, 485 stress, 468, 479 temperature, 468–471, 479, 482, 485 Diagnostic system, 511, 536, 537, 555 Dial size, 670 Digital particle image velocimetry (DPIV), 681 Dilution systems, 513 Direct action, 624 Discontinuity, 440 Distributed control systems, 634 Disturbance, 626 Documenting failure, 429 Dominate lag processes, 622 Dose response, 493 Draft, 304 Drive pulley, 6, Drive wheel, Ductile fracture, 422, 450 Ductility, 422 Durometer, 115 Duragauge, 669 Dust explosion, 494, 516 Dynamic monitoring, 438 Economic criteria, 554 Economizer, 317, 322 Elastic limit, 419 Elasticity of modulus, 418 Elastomer, 107, 114 properties, 151 Elelectronic sources of toxicity, 491 Emergency shutdown, 438 Emissions, 107 regulation, 132 E-modulus, 418 Energy, seal cost, 133 Engineering economics, Erosion, 423 Erosion corrosion, 441 Erosive wear, 423 Evaluation hazard properties, 515, 530 Event tree, 530 Expansion, 467, 480–486 Expansion joints, 147 selection, 149 Expert system, 504, 555 Explosion, 489, 494, 514, 523 Explosion energy, 514 Explosion index, 496 Explosion pressure, 514 Explosion prevention, 543 Fabrication 439 Failure analysis and interpretation, Failure defined, 414 Failure examination, 432 Failure mode effect analysis, 414 Failure mode worksheet, 431 Failure, 308, 309, 467, 469, 475, 479–481 analysis, mechanical seals, 142 of materials and machines, 416 Fasteners, 159 Fatigue, 420, 468, 479–481 Fatigue analysis, 446 Fault event, 503 Fault tree, 499, 509, 536, 552 Feed forward control, 633 Fetoxicity, 493, 515 Fibers, 108 acrylic, 127 aramid, 127 cellulosic, 126 ceramic packing, 130 fluorocarbon, 127 glass, 126 graphite, 127 mineral, 126 pate, 127 vegetable, 116, 126 Field devices, 619 Filters, Filtration, 318 Final control element, 619 heating elements, 633 solenoid valves, 633 time-proportional, 633 Fire damage, 447 Fire protection, 496 Fired boilers, 445 Fitness for service, 436 Flammability limits, 494 Flammable material, 493 Flange backer, 121 face surface, 119 facing, 121 slip-on, 121 stub-end, 121 weld-neck, 121 Flaring system, 573 Flash point, 493 Flaw, 440 Flow limiter, 664 Flowmeter, 663–664, 321 Flue gas system, 154 Fluid sealing association, 148 Fly ash system, 154 FMEA, 414 Foaming, 318 Force, 417 Fracture, 421, 468 Fracture profile, 421 Fretting, 441 Frictional force, 418 Fuel, 398 Functional testing, 542 Galvanic corrosion, 426 Gas pressure, 663–664 surge, 663 velocity, 663–664 Gaskets, 107 construction, 113 corrugated metal core, 117 double jacketed metal, 117 fillers, 112 furnace door, 130 kammprofile, 117 manufacturing, 114 metal, 117 selection, 123 spiral wound, 112, 117 Gasketed joints, 119 Gauge failure, 669 General process hazards, 497 General safety review, 541 Granular activated carbon (GAC), 94 Graphite die-formed, 129 flexible, 114 foil, 127 Gravitational force, 417 Hardness rubber, 115 shore, 115 Hazard, 31, 33, 490 analysis, 491 impact reducing, 556 of an explosion, 31, 33, 521 operability study, 501–502 potential, 512–513, 521 Heat, 306, 326 INDEX Heat-affected zone (HAZ), 440 Heaters, 445 Heat exchangers, 121, 141 Helical chute, 10 Helix, 17–18 Hose delivery, 663 barb, 664 Human injury, 545 Hydrodynamics, 681 Hydrofoil, 683 Hydrogen, 442 Hydrostatic end force, 123 IAE, 626 Ignition, 494 Impact wear, 423 Impeller, 682 Inferred analysis, 414 In-floor, 4, 9, 12, 19, 23 Information sources of toxicity, 491 Installation cartridge seal, 136 expansion joint, 155–156 mechanical seal, 140 packing a pump, 130 valve packing adjustment, 131 Instrumentation for detection, 491 Integral response, 624 Ionizing radiation, 495 ISE, 626 Isotopes, 495 Joint assembly, 124 Maintenance activity, 549–550 Management of change (MOC), 571 Manual mode, 625 Material, primary, secondary, tertiary, Material factor, 497 Material handling, 1, 6, 28 Maximum allowable working pressure, 450 Maximum explosion pressure, 517, 524 Measure of severity, 512 Measured variable, 619 Mechanical damage, 447 Mechanical integrity, 435 Media compatibility-carbon seal, 137 viscous liquid sealing, 139 Membranes, Meta system, 508, 510 Method for safety analysis, 528 Microbial corrosion, 441 Microfiltration (MF), 94 MIG gas, 663–664 shielding, 663–664 Minimum allowable temperature, 452 Minimum ignition energy, 495 Minimum metal temperature, 452 Mixers, 5, 123 Mixing, 681–682 Modes, control, 625 Molecular weight cutoff (MWCO), 90 Multiloop control, 629 Multiple lag processes, 622 Kinetic distribution, 424 Lag, 621 Laser doppler anemometry (LDA), 681 Laser induced fluorescence (LIF), 681 Leak rates, 119 Leak test, 664 Leakage drip chart, 133 pump, 130 Level control, 622 light-duty, 10 load bearing, 16 Localized corrosion, 441 Location, Log removal value (LRV), 91 Logic framework, 506 Loop tuning, 625 Loss prevention, 489 Lower design temperature, 452 Lower explosion limit (LEL), 521 Lowest ambient temperature, 452 Lubricants, 110 Machine, primary, secondary, tertiary, Maintenance, 542, 548 Nitrates, 442 Nondestuctive testing, 438 Normal distribution curve, 424 Normal force, 417 Nozzle, 472–473, 482, 486 Observable variables, 506 Offset limit, 419 Oil analysis, 438 On-floor, 4, 7, 10, 12, 15, 17, 25, 27, 28 Open loop method, 627 Open-blade turbine 683 Operability study, 501 Operability study and hazard, 502 Operating manual, 545 Operating systems, 540 Optimal policy, 553 O-ring metal, 118 self energizing metal, 118 Oxidation, 425 Oxidizing agents, 425 Packing braided, 126 compression, 125 construction, 128 gland, 125 materials, 126 selection, 129 Partial fatigue, 670 Particle size, 428 Pascal, 418 Pay-back period, 30 Peening, 421 Performance monitoring, 438 pH chart, 160 pH scale, 159 Phase media, 669 PID, 619 Pipe(s), 5, 467 design, external corrosion, 51 internal corrosion, 52 maintenance, 58 material, 48 network, 48 strength, 46 supports, 468, 482–483 toughness, 46 weldability, 48 Pipeline coatings, 58 failure, 50 gas, 663 inspection, 54 leak detection, 56 repair, 59 Piping, 467, 468 flange joint, 120 mechanical integrity, movements, 149 Pitched-blade turbine, 683 Pitting corrosion, 441 Pitting development, 425 Plant history, 656, 670 Plant modification, 554–555 Plant safety optimization, 553, 555 Plug, 320 Point of inflection, 622 illustrated, 623 use in tuning, 626 vs number of lags, 623 Poisson ratio, 459 Polymerization, 428 Polytetrafluoroethylene, 110, 114 Potential causes, 415 Potential failure effects, 415 Potential failure modes, 415 Powdered activated carbon (PAC), 94 Pre-startup safety review, 564 Predictive maintenance, 414, 438 Pressure, 428, 467 external, 468, 470, 475, 477, 482, 485 internal, 470–472, 475, 481–482, 484–485 695 696 INDEX Pressure gauge, 669 forward-acting, 665 operating ratio, 667 reverse-acting, 666 Pressure relief valve, 665 Pressure vessel, design, Preventative maintenance, 414 Primary creep, 420 Priming, 319 Procedure, 543 Process, 3, 620 Process component function, Process component performance criteria, Process compressors, Process control, Process control monitoring systems, 540 Process control safety system, 539, 541 Process control system function, 540 Process equipment operation, Process gain, 623 Process hazard analysis checklist, 570 Process hazard revalidation, 565 Process measurement, Process media, 656 Process modeling, Process operation and hazard, 501 Process plant reliability, Process safety, 6, 666 Process safety information, 558 Process safety management, 559 Process simulation, Process time constant, 623, 627 Process vessel, mechanical integrity, Production practice, 546 Programmable logic controller (PLC), 92, 634 Progression of ductile fracture, 422 Project hazard analysis, 565 Propeller, 683 Property changes, 423 Proportional response, 624 Proportionality limit, 419 Pseudo dead time, 623, 627 PTFE, 110, 114 Public awareness, 557 Pumps, 4, 122, 313 Qualitative model developing, 505 Qualitative risk analysis, 505 Quantitative assessment, 500 Quarter wave decay, 625 Radiation resistance, 127 Rate of fatigue, 421 Rate of pressure rise, 518 Ratio control, 632 from another loop, 632 modes, 623 reaction, 467, 478, 483 Reactive maintenance, 414 Reactors, 123 Redesign, 315 Reliability, 534, 536, 557 Remediation cost, 534 Repair, 542 Report, 565–566 Requirements, 620 Residual stress, 459 Response, 621 dead time, 621 lags, 621 process, 620 sensor, 620 steady-state, 620 Retrofitting pilot, 542 Retrofitting, 315 Return idlers, Revalidation, 566 Reverse action, 624 Reverse osmosis (RO), 95 Risk analysis, 503 Risk assessment, 500, 578 Risk characterization, 500 Risk measure method, 582 Risk of fire, 516 Risk parameters modeling, 553 Root cause, 430 Rotating drum, 23 Rotation speed, 18 Rubber, 107 compression set, 116 elongation, 116 modulus of elasticity, 116 properties, 151 resilience, 116 sheet, 114 tensile strength, 115 Rushton turbine, 683 Safe plant operation, 543, 545 Safe processing, 538 Safety and economy, 539 Safety and reliability, 557 Safety factor, 665 Safety maintenance, 548 Safety management, 526, 527 Safety mangement standard, 511 Safety rating, 511 Sampling, 543–544 Sampling with vacuum, 544 Scale, 306 Scavenger, 324 Scenario, 506–507 Scrubber system, 153 Seal(s) balanced, 135 barrier fluid, 140–141 bellows, 135 buffer fluid, 140 buffer system, 140 construction, 113 double mechanical, 135, 140 flushing fluid, 141 inflatable, 116 lip, 135 mechanical face type, 134 metal C-seal, 118–119 pusher, 135 rotary, 135 spring energized, 118 stationary, 135 tandem mechanical, 140 Sealing, 107 Sealing devices, 5, 107 Sealing surface, 119 Seamless pipe, 45 Selection, sealing devices, 157 Self-unloading, Sensors, 654 Serpentine, 316 Sodium bisulfate (SBS), 94 Sodium metabisulfite (SMBS), 96 Soft criterion, 667 Solenoid, 320–321 Solid lubricants, 128 Sorting, 6, 16, 20–22, 26 Sources of deposit formation, 427 Sources of failure, 416 Soya bean plant, 532–533 Special hazard, 490 Special process hazards, 497 Speed rating-packing, 130 Splatter, 440 Spring force, 417 Stainless steel, 442 Steady-state creep, 420 Steam, 397, 303, 305 Steam traps, Step polymerization, 427 Storage tanks, Strain, 418 Strain vs time creep, 420 Strength, 418 Stress, 418, 467 allowable, 468–470, 472, 479, 486 analysis, 450, 467, 469, 479 axial, 469, 470, 485 bearing, 483 bending, 471, 480–481, 483, 486 circumferential, 467, 469, 470, 472, 485 compressive, 468 concentration, 470, 474, 480, 481 corrosion, 467, 468 creep, 470 formula, 472 general, 480 global, 478 hoop, 469 intensity, 480–481, 486 limit, 469 local, 478–480 longitudenal, 470, 472 maximum, 479, 485 membrane, 468, 480–481, 483, 485 occasional, 470 peak, 480 primary, 468, 470, 479, 480, 485 radial, 470 secondary, 470, 479 shear, 479 tangential, 470, 471 torsional, 485, 486 Stress corrosion cracking, 53 Stress intensity factor, 450 INDEX Study, 529 Stuffing box, 125 Support, 468, 470, 471, 475, 478, 481–484 Surface finish, 120 serrated, 124 Symptom, 506, 563 Systematic safety analysis, 506–507 Taking advantage of failure, 415 Temperature, 423 Temperature limits, metals, 111 Temperature measurement, 438 Temperature range, 656 Tensile creep, 419 Tensile strength, 464 Tension force, 418 Tertiary creep, 420 Test report, 543 Thermal analysis, 414 Thermal shock, 424 Thermometers bimetallic, 653 infrared, 655 liquid-filled glass, 653 resistance, 655 thermocouple, 654 Tooth disk, 683 Toughness, 419 Toxic materials, 491, 493 Toxicokinetics, 493 Toxicology, 490 Transmembrane pressure (TMP), 90 Transport, 6, 7, 12, 13, 22, 24, 27 Troubleshooting expansion joint, 156 mechanical seals, 146 True elastic, 419 True elastic limit, 419 Turbulence, 681 Typical crystal lattice structure, 422 Ultimate strength 459 Ultrafiltration (UF), 90 Ultrasonic analysis, 414 Unit load, 4, 9–15, 18–19, 21, 23–26, 28 Upgrading, 315 Upper and lower yield points, 419 Vacuum, 495 Valves, 121–124, 445 actuator, 122 packing, 131 Velocity, 663–664 Vent piping, 495 Vessel, 467, 681–682 pressure, 467–468, 470–472, 474, 481–482 horizontal, 478, 479 Vibration analysis, 414 VisiMix, 681 Volatile substance, 513 Voltage, 321 VRC, 25 Waste water diagnostic system, 553, 555 Water system circulating, fresh, 153 circulating, salt, 153 condensate, 153 service, nuclear, 153 Water waste treatment, 553–554 water, ultra-pure, 154 Wear, 422 Wearing, 36 Weld, 440 Welded pipe, 45 Welding, 308 Wetted parts, 669 Yield, 419, 467, 469–470, 480, 486 Yield strength, 459 Yield stress, 419 Young modulus, 459 Ziegler–Nichols tuning, 626 closed loop, 628 open loop, 627 697