Compressors: Selection and Sizing

569 Pages·1997·33.894 MB·English

by  Royce N. Brown

COMPRESSORS
imiMiiiiffiii^fiTfa^
SELECTION AND SIZING
P_ Gulf Professional Publishing
H an imprint of Butterworth-Heinemann

Dedication
To June,
for her love and encouragement
to keep me moving.
Copyright © 1986, 1997 by Butterworth-Heinemann. All
rights reserved. Printed in the United States of America. This
book, or parts thereof, may not be reproduced in any form
without permission of the publisher.
Originally published by Gulf Publishing Company,
Houston, TX.
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10 9 8 7 6 5 4 3 2
Library of Congress Cataloging-in-Publication Data
Brown, Royce N.
Compressors : selection & sizing / Royce N.
Brown.—2nd ed.
p. cm.
Includes bibliographical references and index.
ISBN 0-88415-164-6
1. Compressors. I. Title.
TJ990.B76 1997
621.5'1—dc20 96-35816
CIP
IV
Preface xiii
Acknowledgments xv
Overview 1
Introduction I
Compression Methods 2
Intermittent Cycle Compressors 4
Reciprocating Compressors. Rotary Compressors.
Continuous Compression Compressors 9
Ejectors. Dynamic Compressors.
2. Basic Relationships 14
Introduction 14
Gas and Vapor 15
Perfect Gas Equation.
Compressibility 17
Generalized Compressibility Charts.
Partial Pressure 18
Gas Mixtures 18
Specific Heat Ratio. Molecular Weight.
Specific Gravity 19
Mixture Compressibility 20
Humidity
Flow
Acoustic Velocity _ 26
Equations of State . 26
Mollier Charts. First Law of Thermodynamics. Second Law of
Thermodynamics.
Theoretical Work 30
Real Gas Exponent. Power. Velocity Head.
Intercooling 41
;
Isothermal Compression.
References 46
:
3. Reciprocating Compressors 48
Description 48
Classification. Arrangement. Drive Methods.
Performance 54
Compression Cycle. Cylinder Displacement. Volumetric Efficiency. Piston
Speed, Discharge Temperature. Power. Valve Loss. Application Notes.
Mechanics 67
Cylinders. Pistons and Rods. Valves. Distance Piece. Rod Packing.
Crankshaft and Bearings. Frame Lubrication. Cylinder and Packing
Lubrication. Cooling. Capacity Control. Pulsation Control.
References ___. 90
4. Rotary Compressors ___ 93
Common Features 93
Arrangements and Drivers.
Helical Lobe 95
History. Operating Principles. Displacement. Dry Compressors. Flooded
Compressors. Flooding Fluid. Application Notes—Dry Compressors.
Application Notes—Flooded Compressors. Casings. Rotors. Bearings and
Seals. Timing Gears. Capacity Control.
V!
Straight Lobe 121
Compression Cycle. Sizing. Applications. Mechanical Construction.
Sliding Vane 126
Compression Cycle. Sizing. Application Notes. Mechanical Construction.
Liquid Piston 130
Operation. Performance, Mechanical Construction.
References 131
; ;
5, Centrifugal Compressors 132
Introduction 132
Classification. Arrangement, Drive Methods.
Performance 147
Compression Cycle. Vector Triangles. Slip. Reaction. Sizing. Fan Laws,
Curve Shape. Surge. Choke. Application Notes.
Mechanical Design 188
;
Introduction. Casings. Diaphragms. Casing Connections. Impellers. Shafts.
Radial Bearings. Thrust Bearings. Bearing Housings. Magnetic Bearings.
Balance Piston. Interstage Seals. Shaft End Seals.
Shaft End Seals 211
Restrictive Seals. Liquid Buffered Seals. Dry Gas Seals. Capacity Control.
Maintenance.
References __ 222
6. Axial Compressors 224
Historical Background
Description
Performance
;
Blades. Compression Cycle. Reaction. Stagger. Curve Shape. Surge. Sizing.
Application Notes.
Mechanical Design 247
Casings. Stators. Casing Connections. Rotor. Shaft. Blading. Bearings.
Balance Piston. Seals. Capacity Control. Maintenance.
References 255
VII
7. Drivers . 256
Introduction 256
;
Electric Motors 25?
Voltage. Enclosures. Totally Enclosed Motors. Division 1 Enclosures. Inert
Gas-Filled. Insulation. Service Factor. Synchronous Motors. Brushless
Excitation. Motor Equations.
Compressor and Motor
Selecting Compressor Motors. Starting Characteristics. Starting Time.
Enclosure Selection. Enclosure Applications.
Variable Frequency Drives 277
Motor.
Steam Turbines 282
Steam Temperature. Speed. Operation Principles. Steam Turbine Rating.
Gas Engines . 292
Gas Turbines 292
Gas Turbine Types. Gas Turbine Economics. Sizing Application.
Expansion Turbines 296
Types, Operation Limits. Power Recovery. Refrigeration. Condensation.
Expander Applications.
References 300
8. Accessories ,_____„ 302
Introduction 302
Lubrication Systems 303
Reservoir. Pumps and Drivers. Relief Valves. Pressure Control Valves.
Startup Control. Check Valves. Coolers. Filters. Transfer Valves.
Accumulators. Seal Oil Overhead Tank. Lube Oil Overhead Tank. Seal Oil
Drainers. Degassing Drum. Piping. System Review. Testing of Lubrication
Systems. Commissioning of Lube Oil Systems.
Dry Gas Seal Systems 323
System Design Considerations. Dry Gas Seal System Control. Dry Gas Seal
System Filters.
Vlll
Gears 328
Gear Design and Application. Rotors and Shafts. Bearings and Seals.
Housing. lubrication.
Couplings 333
Introduction. Ratings. Spacers. Hubs. Gear Couplings. Alignment. Flexible
Element Couplings. Limited End-Float Couplings.
Instrumentation 342
Overview. Pressure. Temperature. Flow. Torque. Speed. Rod Drop Monitor.
Molecular Weight.
Vibration 349
Vibration Sensors. Seismic Sensors. Proximity Sensors. Axial Shaft Motion.
Radial Shaft Vibration.
Control 356
Analysis of the Controlled System. Pressure Control at Variable Speed.
Volume Control at Variable Speed. Weight Flow Control with Variable
Stator Vanes. Pressure Control at Constant Speed. Volume Control at
Constant Speed. Weight Flow Control at Constant Speed. Anti-Surge
Control.
References .
;
9. Dynamics 368
Introduction
Balance
;
Basics. Unbalance.
Balance Methods 374
Shop Balance Machine. High Speed Balancing. Field Balancing.
Reciprocating Shaking Forces 378
Rotary Shaking Forces 382
Rotor Dynamics 384
Damped Unbalance Response. Torsionals. Torsional Damping and Resilient
Coupling.
References , 400
IX