Pump Characteristics and Applications 2nd Edition By Michael Volk

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Pump Characteristics and Applications 2nd Edition By Michael Volk

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Preface to the Second Edition

Thankfully, the laws of physics have not changed since the
first edition of this book was written in 1996. Therefore, virtually
everything about pump selection, sizing, system analysis,
and other aspects of pump hydraulics remains
unchanged from the first edition. There have, however, been
a number of innovations in the world of pumps, which are
introduced in this second edition. This edition also expands
the material on many components of typical pump installations
that were only briefly covered in the first edition, if at
all. Some of the most important new or expanded topics covered
in this second edition include:
include NPSH analysis for closed systems, expansion
of the discussion on NPSH margin, and system head
curve development for existing systems and for parallel
pumping systems.
eternity, and so the entire section of this chapter
covering software used to design and analyze pump
piping systems has been completely rewritten. A new
CD is included with the second edition of the book,
demonstrating one such software tool, including solving
some of the problems covered in the book.
© 2005 by Taylor & Francis Group, LLC
Chapter 1 — Several new types of positive displace-
Chapter 2 — Important new topics in this chapter
Chapter 3 — In the world of software, 9 years is an
been added to provide in-depth coverage of two very
important and relevant topics: pump couplings and
electric motors. Additionally, several types of centrifugal
pumps that were not included in the first edition
are covered in this chapter.
on O-rings used in pumps, as well as additional information
about sealless pumps.
included in this chapter. The first is an in-depth discussion
of variable-frequency drives. Second, this
chapter includes a section covering pump life-cycle
cost, an innovative approach to the study of the cost
of pumping equipment that looks way beyond the
capital cost of the pump.
sion of metallic corrosion in pumps, as well as discourse
on elastomers commonly used in pumps for
sealing components.
include ten methods to prevent low flow damage in
pumps, and a much more detailed discussion of vibration,
including a detailed vibration troubleshooting
chart.
Chapter 4 — Entire new sections of this chapter have
Chapter 5 — This chapter has an entire new section
Chapter 6 — Two major additions to the book are
Chapter 7 — This chapter has added in-depth discus-
Chapter 8 — New topics covered in this chapter
Acknowledgments
Thanks to my colleagues in the pump field who provided input
for this second edition, or who reviewed particular sections of
it. Finally, I wish to thank my daughter Sarah, who typed
major portions of the new material for this edition.
© 2005 by Taylor & Frawncisw Growup, .LTLCechbooksyard.com

Preface to the First Edition

This book is a practical introduction to the characteristics and
applications of pumps, with a primary focus on centrifugal
pumps. Pumps are among the oldest machines still in use
and, after electric motors, are probably the most widely used
machines today in commercial and industrial activities.
Despite the broad use of pumps, this subject is covered only
briefly in many engineering curricula. Furthermore, companies
which use pumps are often unable to provide their engineers,
operators, mechanics, and supervisors the kind of
training in pump application, selection, and operation that
this vital equipment merits.
The purpose of this book is to give engineers and technicians
a general understanding of pumps, and to provide the
tools to allow them to properly select, size, operate, and maintain
pumps. There are numerous books on the market aout
pumps, but most of them are very, very technical, and are
mainly design oriented, or else are directed to a specific niche
market. I have attempted to provide practical information on
pumps and systems to readers with with all levels of experience,
without getting so immersed in design details as to
overwhelm the reader.
This book begins with the basics of pump and system
hydraulics, working gradually to more complex concepts. The
topics are covered in a clear and concise manner, and are
accompanied by examples along the way. Anyone reading the
material, regardless of education and experience with pumps,
will be able to achieve a better understanding of pump characteristics
and applications.
© 2005 by Taylor & Frawncisw Growup, .LTLCechbooksyard.com
xvi Preface to the First Edition
While it is not possible to cover pump hydraulics without
getting into some mathematics, this book covers the subject
without resorting to differential equations and other high
level matchematics that most people forgot right after school.
For the reader who is interested in a more complex or sophisticated
approach to particular topics, or who wants additional
information in a given area, references are made to other
sources which provide a more analytical approach.
A theme that is repeated throughout this book is that all
aspects of pumps — from system design, to pump selection,
to piping design, to installation, to operation — are interrelated.
Lack of attention to the sizing of a pump or improper
design of the piping system can cause future problems with
pump maintenance and operation. Even the most precisely
sized pump will not perform properly if its installation and
maintenance are not performed carefully. A better understanding
of how these issues are related will help to solve
problems or to prevent them from occurring in the first place.
In addition to a thorough treatment of the fundamentals,
this book also provides information on the current state of
the art of various technologies in the pump field. Variable
speed pumping systems, sealless pumps, gas lubricating noncontacting
mechanical seals, and nonmetallic pumps are
examples of recent technological trends in the pump industry
which are introduced in this book. Computer software for
and a demonstration CD is included with this book. This is
another example of a powerful new technology related to
pumps that is covered in this book.
Because the book focuses on pump applications and characteristics,
rather than on design, it is intended for a broader
audience than typical books about pumps. The readership for
this book includes the following:
• Engineers — This book has broad appeal to mechanical,
civil, chemical, industrial, and electrical engineers.
Any engineer whose job it is to design or modify
systems; select, specify, purchase, or sell pumps; or
oversee operation, testing, or maintenance of pumping
equipment will find this book very helpful.
© 2005 by Taylor & Francis Group, LLC
system design and pump selection is previewed in Chapter 3,
• Engineering Supervisors — Because they have broad
responsibility for overseeing the design and operation
of pumps and pump systems, engineering supervisors
will benefit from the integrated systems approach
provided in this book.
• Plant Operators —Employees of plants which utilize
pumps are required to oversee the operation of the
pumps, and often their maintenance, troubleshooting,
and repair. A better understanding of hydraulics
and applications will help these people do a better
job of operating their pumps most efficiently while
reducing maintenance costs and downtime.
• Maintenance Technicians — Maintenance personel
and their supervisors can do a much better job of
installing, maintaining, troubleshooting, and repairing
pumps if they have a better understanding of how
pumps are applied and operated in a system.
• Engineering Students — The “real world” problems
which are presented in this book demonstrate to students
that a pump is more than a “black box.” Many
university engineering departments are expanding
their technology program to better prepare students
for jobs in industry. This book can make an important
contribution to a program in industrial machinery.
Formulae used in this book will generally be stated in
United States Customary System (USCS) units, the system
most widely used by the pump industry in the United States.
Appendix B at the end of this book provides simple conversion
formulae from USCS to SI (metric) units. The most common
terms mentioned in this book will be stated in both untis.
I wish to thank my colleagues in the pump field who
reviewed various sections of this book, or who assisted in
obtaining materials and illustrations. I’m especially grateful
to my friends Jim Johnston, Paul Lahr, and Buster League,
who reviewed the entire manuscript and provided me with
valuable feedback. Final thanks go to my wife, Jody Lerner,
for her word processing and editorial skills, as well as for her
patience and encouragement.
Michael W. Volk, P.E., is President of Volk & Associates, Inc.,
company specializing in pumps and pump systems. Volk’s
services include pump training seminars; pump equipment
evaluation, troubleshooting, and field testing; expert witness
for pump litigation; witnessing of pump shop tests; pump
market research; and acquisition and divestiture consultation
and brokerage. A member of the American Society of Mechanical
Engineers (ASME), and a registered professional engineer,
Volk received the B.S. degree (1973) in mechanical
engineering from the University of Illinois, Urbana, and the
M.S. degree (1976) in mechanical engineering and the M.S.
degree (1980) in management science from the University of
Southern California, Los Angeles. He may be contacted at
© 2005 by Taylor & Francis Group, LLC
Oakland, California, www.volkassociates.com, a consulting

Contents

1 Introduction to Pumps……………………………………….1
I. What Is a Pump?…………………………………………………… 1
II. Why Increase a Liquid’s Pressure?…………………………. 2
III. Pressure and Head………………………………………………… 3
IV. Classification of Pumps………………………………………….. 5
A. Principle of Energy Addition …………………………….. 5
1. Kinetic ……………………………………………………….. 5
2. Positive Displacement …………………………………. 5
B. How Energy Addition Is Accomplished ……………… 7
C. Geometry Used ………………………………………………… 7
V. How Centrifugal Pumps Work ……………………………….. 7
VI. Positive Displacement Pumps ………………………………. 14
A. General………………………………………………………….. 14
B. When to Choose a P.D. Pump………………………….. 15
C. Major Types of P.D. Pumps……………………………… 22
1. Sliding Vane Pump……………………………………. 24
2. Sinusoidal Rotor Pump ……………………………… 25
3. Flexible Impeller Pump …………………………….. 25
4. Flexible Tube (Peristaltic) Pump………………… 26
5. Progressing Cavity Pump ………………………….. 27
6. External Gear Pump …………………………………. 29
7. Internal Gear Pump………………………………….. 33
8. Rotary Lobe Pump…………………………………….. 33
9. Circumferential Piston and Bi-Wing
Lobe Pumps………………………………………………. 35
10. Multiple-Screw Pump………………………………… 36
11. Piston Pump……………………………………………… 38
12. Plunger Pump…………………………………………… 40
13. Diaphragm Pump ……………………………………… 41
14. Miniature Positive Displacement Pumps ……. 47
2 Hydraulics, Selection, and Curves …………………..51
I. Overview …………………………………………………………….. 51
II. Pump Capacity ……………………………………………………. 54
III. Head …………………………………………………………………… 54
A. Static Head ……………………………………………………. 56
B. Friction Head…………………………………………………. 58
C. Pressure Head ……………………………………………….. 66
D. Velocity Head …………………………………………………. 70
IV. Performance Curve………………………………………………. 71
V. Horsepower and Efficiency …………………………………… 80
A. Hydraulic Losses ……………………………………………. 82
B. Volumetric Losses…………………………………………… 82
C. Mechanical Losses………………………………………….. 83
D. Disk Friction Losses……………………………………….. 83
VI. NPSH and Cavitation ………………………………………….. 89
A. Cavitation and NPSH Defined ………………………… 89
1. NPSHa ……………………………………………………… 98
2. NPSHr………………………………………………………. 99
B. Calculating NPSHa: Examples ………………………. 101
C. Remedies for Cavitation ……………………………….. 102
D. More NPSHa Examples…………………………………. 106
E. Safe Margin NPSHa vs. NPSHr ……………………… 109
F. NPSH for Reciprocating Pumps…………………….. 114
VII. Specific Speed and Suction Specific Speed…………… 116
VIII. Affinity Laws …………………………………………………….. 122
IX. System Head Curves………………………………………….. 127
X. Parallel Operation ……………………………………………… 139
XI. Series Operation………………………………………………… 146
XII. Oversizing Pumps ……………………………………………… 152
XIII. Pump Speed Selection………………………………………… 155
A. Suction Specific Speed ………………………………….. 156
B. Shape of Pump Performance Curves ……………… 156
C. Maximum Attainable Efficiency…………………….. 157
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Contents xxiii
D. Speeds Offered by Manufacturers………………….. 158
E. Prior Experience…………………………………………… 159
3 Special Hydraulic Considerations………………….161
I. Overview …………………………………………………………… 161
II. Viscosity ……………………………………………………………. 162
III. Software to Size Pumps and Systems …………………. 185
A. General………………………………………………………… 185
B. Value of Piping Design Software……………………. 186
C. Evaluating Fluid Flow Software ……………………. 186
D. Building the System Model …………………………… 187
1. Copy Command……………………………………….. 189
2. Customize Symbols………………………………….. 190
3. CAD Drawing Features……………………………. 190
4. Naming Items …………………………………………. 190
5. Displaying Results…………………………………… 190
6. The Look of the Piping Schematic ……………. 191
E. Calculating the System Operation…………………. 191
1. Sizing Pipe Lines…………………………………….. 192
2. Calculating Speed……………………………………. 192
3. Showing Problem Areas …………………………… 192
4. Equipment Selection ……………………………….. 192
5. Alternate System Operational Modes……….. 193
F. Communicating the Results ………………………….. 193
1. Viewing Results within the Program………… 193
2. Incorporating User-Defined Limits …………… 194
3. Selecting the Results to Display ………………. 194
4. Plotting the Piping Schematic………………….. 194
5. Exporting the Results ……………………………… 194
6. Sharing Results with Others……………………. 195
7. Sharing Results Using a Viewer Program … 195
G. Conclusion……………………………………………………. 195
H. List of Software Vendors……………………………….. 196
IV. Piping Layout ……………………………………………………. 196
V. Sump Design……………………………………………………… 200
VI. Field Testing ……………………………………………………… 203
A. General………………………………………………………… 203
B. Measuring Flow……………………………………………. 205
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xxiv Contents
1. Magnetic Flowmeter………………………………… 205
2. Mass Flowmeter ……………………………………… 205
3. Nozzle …………………………………………………….. 205
4. Orifice Plate ……………………………………………. 206
5. Paddle Wheel ………………………………………….. 206
6. Pitot Tube……………………………………………….. 206
7. Segmental Wedge…………………………………….. 207
8. Turbine Meter…………………………………………. 207
9. Ultrasonic Flowmeter………………………………. 207
10. Venturi……………………………………………………. 208
11. Volumetric Measurement…………………………. 208
12. Vortex Flowmeter ……………………………………. 208
C. Measuring TH………………………………………………. 209
D. Measuring Power………………………………………….. 211
E. Measuring NPSH …………………………………………. 212
4 Centrifugal Pump Types and Applications……213
I. Overview …………………………………………………………… 213
II. Impellers …………………………………………………………… 215
A. Open vs. Closed Impellers …………………………….. 215
B. Single vs. Double Suction ……………………………… 223
C. Suction Specific Speed ………………………………….. 225
D. Axial Thrust and Thrust Balancing……………….. 227
E. Filing Impeller Vane Tips ……………………………… 230
F. Solids Handling Impellers …………………………….. 232
III. End Suction Pumps……………………………………………. 233
A. Close-Coupled Pumps……………………………………. 233
B. Frame-Mounted Pumps ………………………………… 237
IV. Inline Pumps …………………………………………………….. 240
V. Self-Priming Centrifugal Pumps…………………………. 242
VI. Split Case Double Suction Pumps ………………………. 245
VII. Multi-Stage Pumps ……………………………………………. 250
A. General………………………………………………………… 250
B. Axially Split Case Pumps ……………………………… 250
C. Radially Split Case Pumps……………………………. 254
VIII. Vertical Column Pumps……………………………………… 256
IX. Submersible Pumps……………………………………………. 260
X. Slurry Pumps…………………………………………………….. 264
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Contents xxv
XI. Vertical Turbine Pumps……………………………………… 268
XII. Axial Flow Pumps ……………………………………………… 277
XIII. Regenerative Turbine Pumps……………………………… 278
XIV. Pump Specifications and Standards ……………………. 279
A. General………………………………………………………… 279
1. Liquid Properties…………………………………….. 280
2. Hydraulic Conditions ………………………………. 280
3. Installation Details………………………………….. 281
B. ANSI……………………………………………………………. 282
C. API………………………………………………………………. 284
D. ISO………………………………………………………………. 286
XV. Couplings ………………………………………………………….. 287
XVI. Electric Motors ………………………………………………….. 291
A. Glossary of Frequently Occurring Motor
Terms…………………………………………………………… 294
1. Amps………………………………………………………. 294
2. Code Letter …………………………………………….. 295
3. Design Letter ………………………………………….. 295
4. Efficiency ………………………………………………… 296
5. Frame Size ……………………………………………… 296
6. Frequency……………………………………………….. 296
7. Full Load Speed………………………………………. 297
8. High Inertial Load…………………………………… 297
9. Insulation Class………………………………………. 297
10. Load Types ……………………………………………… 297
11. Phase ……………………………………………………… 298
12. Poles……………………………………………………….. 298
13. Power Factor …………………………………………… 298
14. Service Factor …………………………………………. 298
15. Slip…………………………………………………………. 299
16. Synchronous Speed………………………………….. 299
17. Temperature……………………………………………. 299
18. Time Rating ……………………………………………. 300
19. Voltage ……………………………………………………. 300
B. Motor Enclosures………………………………………….. 300
1. Open Drip Proof………………………………………. 300
2. Totally Enclosed Fan Cooled…………………….. 301
3. Totally Enclosed Air Over………………………… 301
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xxvi Contents
4. Totally Enclosed Non-Ventilated ………………. 301
5. Hazardous Location…………………………………. 302
C. Service Factor ………………………………………………. 302
D. Insulation Classes ………………………………………… 303
E. Motor Frame Size…………………………………………. 303
1. Historical Perspective………………………………. 303
2. Rerating and Temperature ………………………. 307
3. Motor Frame Dimensions ………………………… 307
4. Fractional Horsepower Motors …………………. 307
5. Integral Horsepower Motors…………………….. 312
6. Frame Designation Variations………………….. 312
F. Single Phase Motors……………………………………… 314
G. Motors Operating on Variable Frequency
Drives ………………………………………………………….. 319
H. NEMA Locked Rotor Code…………………………….. 321
I. Amps, Watts, Power Factor, and Efficiency …….. 322
1. Introduction ……………………………………………. 322
2. Power Factor …………………………………………… 322
3. Efficiency ………………………………………………… 323
4. Amperes………………………………………………….. 325
5. Summary………………………………………………… 325
5 Sealing Systems and Sealless Pumps…………….327
I. Overview …………………………………………………………… 327
II. O-Rings……………………………………………………………… 328
A. What Is an O-Ring?………………………………………. 328
B. Basic Principals of the O-Ring Seal……………….. 329
C. The Function of the O-Ring…………………………… 329
D. Static and Dynamic O-Ring Sealing
Applications …………………………………………………. 330
E. Other Common O-Ring Seal Configurations…… 330
F. Limitations of O-Ring Use…………………………….. 333
III. Stuffing Box and Packing Assembly ……………………. 333
A. Stuffing Box …………………………………………………. 334
B. Stuffing Box Bushing ……………………………………. 334
C. Packing Rings ………………………………………………. 335
D. Packing Gland………………………………………………. 336
E. Lantern Ring………………………………………………… 337
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Contents xxvii
IV. Mechanical Seals ……………………………………………….. 338
A. Mechanical Seal Advantages …………………………. 338
1. Lower Mechanical Losses ………………………… 338
2. Less Sleeve Wear …………………………………….. 338
3. Zero or Minimal Leakage…………………………. 338
4. Reduced Maintenance ……………………………… 339
5. Seal Higher Pressures……………………………… 339
B. How Mechanical Seals Work …………………………. 339
C. Types of Mechanical Seals…………………………….. 343
1. Single, Inside Seals …………………………………. 343
2. Single, Outside Seals……………………………….. 345
3. Single, Balanced Seals …………………………….. 346
4. Double Seals …………………………………………… 347
5. Tandem Seals………………………………………….. 349
6. Gas Lubricated Non-Contacting Seals………. 351
V. Sealless Pumps………………………………………………….. 352
A. General………………………………………………………… 352
B. Magnetic Drive Pumps …………………………………. 354
1. Bearings in the Pumped Liquid ……………….. 357
2. Dry Running …………………………………………… 358
3. Inefficiency ……………………………………………… 358
4. Temperature……………………………………………. 358
5. Viscosity …………………………………………………. 359
C. Canned Motor Pumps …………………………………… 359
1. Fewer Bearings……………………………………….. 360
2. More Compact…………………………………………. 361
3. Double Containment ……………………………….. 361
4. Lower First Cost……………………………………… 361
6 Energy Conservation and Life-Cycle Costs …..363
I. Overview …………………………………………………………… 363
II. Choosing the Most Efficient Pump ……………………… 364
III. Operating with Minimal Energy…………………………. 372
IV. Variable-Speed Pumping Systems ………………………. 373
V. Pump Life-Cycle Costs……………………………………….. 395
A. Improving Pump System Performance:
An Overlooked Opportunity?…………………………. 395
B. What Is Life-Cycle Cost? ………………………………. 397
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xxviii Contents
C. Why Should Organizations Care about
Life-Cycle Cost? ……………………………………………. 397
D. Getting Started…………………………………………….. 399
E. Life Cycle Cost Analysis ……………………………….. 399
1. Cic — Initial Investment Costs…………………. 401
2. Cin — Installation and Commissioning
(Start-up) Costs ………………………………………. 402
3. Ce — Energy Costs ………………………………….. 403
4. Co — Operation Costs………………………………. 404
5. Cm — Maintenance and Repair Costs……….. 404
6. Cs — Downtime and Loss of Production
Costs ………………………………………………………. 406
7. Cenv — Environmental Costs, Including Disposal
of Parts and Contamination
from Pumped Liquid ……………………………….. 407
8. Cd — Decommissioning/Disposal Costs,
Including Restoration of the Local
Environment …………………………………………… 407
F. Total Life-Cycle Costs …………………………………… 408
G. Pumping System Design……………………………….. 408
H. Methods for Analyzing Existing Pumping
Systems ……………………………………………………….. 413
I. Example: Pumping System with a Problem
Control Valve ……………………………………………….. 414
J. For More Information……………………………………. 419
1. About the Hydraulic Institute………………….. 419
2. About Europump …………………………………….. 419
3. About the U.S. Department of Energy’s
Office of Industrial Technologies ………………. 421
7 Special Pump-Related Topics …………………………423
I. Overview …………………………………………………………… 423
II. Variable-Speed Systems……………………………………… 424
III. Sealless Pumps………………………………………………….. 425
IV. Corrosion…………………………………………………………… 426
1. Galvanic, or Two-Metal Corrosion…………….. 428
2. Uniform, or General Corrosion…………………. 429
3. Pitting Corrosion …………………………………….. 430
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Contents xxix
4. …………………………… 430
5. Erosion Corrosion ……………………………………. 431
6. Stress Corrosion ……………………………………… 431
7. Crevice Corrosion ……………………………………. 432
8. Graphitization or Dezincification
Corrosion ………………………………………………… 432
V. Nonmetallic Pumps……………………………………………. 432
VI. Materials Used for O-Rings in Pumps ………………… 435
A. General………………………………………………………… 435
B. Eight Basic O-Ring Elastomers …………………….. 437
1. Nitrile (Buna N) ……………………………………… 437
2. Neoprene ………………………………………………… 437
3. Ethylene Propylene …………………………………. 438
4. Fluorocarbon (Viton) ……………………………….. 438
5. Butyl ………………………………………………………. 439
6. Polyacrylate…………………………………………….. 439
7. Silicone …………………………………………………… 439
8. Fluorosilicone ………………………………………….. 440
VII. High-Speed Pumps…………………………………………….. 441
VIII. Bearings and Bearing Lubrication ……………………… 446
IX. Precision Alignment Techniques …………………………. 447
X. Software to Size Pumps and Systems …………………. 449
8 Installation, Operation, and Maintenance …….451
I. Overview …………………………………………………………… 451
II. Installation, Alignment, and Start-Up ………………… 452
A. General………………………………………………………… 452
B. Installation Checklist……………………………………. 453
1. Tag and Lock Out……………………………………. 453
2. Check Impeller Setting ……………………………. 453
3. Install Packing or Seal…………………………….. 453
4. Mount Bedplate, Pump, and Motor…………… 454
5. Check Rough Alignment ………………………….. 454
6. Place Grout in Bedplate…………………………… 454
7. Check Alignment …………………………………….. 456
8. Flush System Piping ……………………………….. 457
9. Connect Piping to Pump ………………………….. 457
10. Check Alignment …………………………………….. 459
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xxx Contents
11. Turn Pump by Hand ……………………………….. 459
12. Wire and Jog Motor…………………………………. 459
13. Connect Coupling ……………………………………. 459
14. Check Shaft Runout ………………………………… 460
15. Check Valve and Vent Positions ……………….. 460
16. Check Lubrication/Cooling Systems………….. 460
17. Prime Pump if Necessary ………………………… 460
18. Check Alignment …………………………………….. 461
19. Check System Components Downstream ….. 461
20. Start and Run Pump……………………………….. 462
21. Stop Pump and Check Alignment…………….. 462
22. Drill and Dowel Pump to Base…………………. 462
23. Run Benchmark Tests ……………………………… 462
III. Operation ………………………………………………………….. 462
A. General………………………………………………………… 462
B. Minimum Flow …………………………………………….. 463
1. Temperature Rise ……………………………………. 464
2. Radial Bearing Loads………………………………. 465
3. Axial Thrust ……………………………………………. 465
4. Prerotation ……………………………………………… 465
5. Recirculation and Separation …………………… 466
6. Settling of Solids……………………………………… 468
7. Noise and Vibration…………………………………. 468
8. Power Savings, Motor Load ……………………… 468
C. Ten Ways to Prevent Low Flow Damage
in Pumps ……………………………………………………… 468
1. Continuous Bypass………………………………….. 470
2. Multi-Component Control Valve System …… 471
3. Variable Frequency Drive ………………………… 472
4. Automatic Recirculation Valve …………………. 473
5. Relief Valve …………………………………………….. 473
6. Pressure Sensor ………………………………………. 475
7. Ammeter…………………………………………………. 475
8. Power Monitor ………………………………………… 475
9. Vibration Sensor ……………………………………… 476
10. Temperature Sensor ………………………………… 476
IV. Maintenance ……………………………………………………… 477
A. Regular Maintenance……………………………………. 477
1. Lubrication……………………………………………… 477
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Contents xxxi
2. Packing …………………………………………………… 478
3. Seals ………………………………………………………. 479
B. Preventive Maintenance ……………………………….. 479
1. Regular Lubrication ………………………………… 480
2. Rechecking Alignment……………………………… 480
3. Rebalance Rotating Element ……………………. 480
4. Monitoring Benchmarks…………………………… 480
C. Benchmarks …………………………………………………. 480
1. Hydraulic Performance ……………………………. 480
2. Temperature……………………………………………. 481
3. Vibration…………………………………………………. 482
V. Troubleshooting …………………………………………………. 489
VI. Repair……………………………………………………………….. 489
A. General………………………………………………………… 489
B. Repair Tips…………………………………………………… 492
1. Document the Disassembly ……………………… 492
2. Analyze Disassembled Pump……………………. 492
3. Bearing Replacement ………………………………. 493
4. Wear Ring Replacement…………………………… 494
5. Guidelines for Fits and Clearances…………… 495
6. Always Replace Consumables…………………… 495
7. Balance Impellers and Couplings …………….. 495
8. Check Runout of Assembled Pump…………… 496
9. Tag Lubrication Status ……………………………. 497
10. Cover Openings Prior to Shipment…………… 497
Appendix A: Major Suppliers of Pumps
in the United States by Product Type……………………499
Appendix B: Conversion Formulae…………………………511
References ………………………………………………………………..525