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An easy-to-understand introduction to slurry pumps and systems
This is the shell or volute of a very large slurry pump.
Reader’s Guide
For Our Customers Past, Present and Future
Editor & Designer Mary A. Sicard Project Editor Thomas Mueller Production Controller Pam Welty Tech Team Bob Courtwright, Tom Wujcik, Richard Inglett, Reab Berry and Kevin Kuehne
Copyright © 2006 GIW Industries Inc./KSB Mining Group
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanic, photocopy, recording or otherwise, without the prior written permission of the copyright owner.
Meet Digsby. He appears whenever we want to give you a mountain of information but only have room for a mole hill. He tells you where to dig deeper in other sources and in the textbook, “Slurry Transport Using Centrifugal Pumps,” written by Drs. Kenneth C. Wilson, Anders Sellgren Roland Clift and GIW’s VP of Engineering Graeme Addie. The textbook is available from Kluwer Publishing (www.wkap.nl).
giwindustries.com Does your slurry have an attitude? Is it caustic? Corrosive? Abrasive? Erosive? (Or some combination thereof?) If so, talk to us. We can make the biggest, baddest, meanest, nastiest slurry behave. We are the experts in slurry transport, so challenge us to solve your production delays or to improve your slurry pumping systems.
Get in touch and stay in touch 5000 Wrightsboro Rd. • Grovetown, Ga. 30813 Phone: 706.863.1011 • Fax: 706.863.5637
A KSB Company
1.888.TECH.GIW (832.4449)
[email protected]
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Slurry Pump Fundamentals
Contents Chapter 1: What Is Slurry? .......................................................... 9 Slurry Pumps vs. Water Pumps....................................................................... 9 Flow Limitations ....................................................................................... 10 Solids Limitations ...................................................................................... 11
Chapter 2: Slurry Pumps Defined ............................................... 13 Markets & Applications for Slurry Pumps ......................................................... 14 Installations ............................................................................................. 14 DRY ............................................................................................................................. 15 SEMI DRY....................................................................................................................... 15 WET ............................................................................................................................ 15
Wear Conditions ....................................................................................... 15
Chapter 3: Slurry Pump Design & Components ............................... 17 Basic Designs............................................................................................ 17 Basic Components ..................................................................................... 17 Impeller .................................................................................................. 18 CLOSED IMPELLERS .......................................................................................................... 18 OPEN IMPELLERS ............................................................................................................. 18
Vane Designs ............................................................................................ 19 Shell ...................................................................................................... 19 SHELL TYPES.................................................................................................................. 19 SPLIT AND SOLID SHELLS ............................................................................................. 19
Suction Liner ........................................................................................... 20 Shaft Seals .............................................................................................. 20 STUFFING BOX ................................................................................................................ 20 MECHANICAL SEAL ........................................................................................................... 20 EXPELLER ..................................................................................................................... 20
Shaft and Bearings ..................................................................................... 21 SHAFT .......................................................................................................................... 21 BEARINGS...................................................................................................................... 21
Drives for Slurry Pumps .............................................................................. 21 BELT DRIVES .................................................................................................................. 21 GEARBOX DRIVES ............................................................................................................ 21 DIRECT DRIVES ............................................................................................................... 21
Chapter 4: Wear Protection ...................................................... 23 Wear ...................................................................................................... 23 Corbrasion™ ............................................................................................. 23
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Selection of Wear Materials ............................................. ............................ 23 HARD METAL CONSTRUCTION ............................................................................................. 24 WHITE IRONS ........................................................................................................... 24 STEELS ................................................................................................................... 24
Elastomer Construction .............................................................................. 25 Ceramic Wear Parts ................................................................................... 25 Corrosion Resistance and Wear Resistance ....................................................... 25 Wear Resistance Range ............................................................................... 26 pH Ranges ............................................................................................... 27
Chapter 5: Hydraulics .............................................................. 29 Pumps and Curves ..................................................................................... 29 PERFORMANCE CURVE ...................................................................................................... 30 SYSTEM CURVE ............................................................................................................... 31 THE INTERSECTION .......................................................................................................... 32
Head ...................................................................................................... 32 NET POSITIVE SUCTION HEAD (NPSH) .................................................................................... 32
Vapor Pressure and Cavitation ...................................................................... 33 CAVITATION ................................................................................................................... 33 NPSHR .......................................................................................................................... 34 NPSHA .......................................................................................................................... 35 CAUSES OF CAVITATION ..................................................................................................... 35 HOW TO FIND THE CAUSE .................................................................................................. 36 TO AVOID CAVITATION ...................................................................................................... 36
Pumping Froth.......................................................................................... 36
Chapter 6: Slurry Pump Systems ................................................ 37 Overview ................................................................................................ 37 Pipe Systems ............................................................................................ 37 Friction Losses ......................................................................................... 39 STRAIGHT PIPES .............................................................................................................. 39 FITTINGS....................................................................................................................... 40 SLURRY EFFECTS ON FRICTION LOSSES ................................................................................. 40 FRICTION LOSSES IN SETTLING SLURRIES ............................................................................... 40 NOMOGRAM FOR DETERMINING DEPOSIT VELOCITY ............................................................ 41 FRICTION LOSSES IN NON-SETTLING SLURRIES ......................................................................... 42
Viscosity ................................................................................................. 42 NEWTONIAN AND NON-NEWTONIAN LIQUIDS ........................................................................... 42 OTHER NON-NEWTONIAN FLUIDS ......................................................................................... 43
Sump Arrangements ................................................................................... 43 Multiple Pump Installations .......................................................................... 44 PUMPS IN A SERIES........................................................................................................... 44 PUMPS IN PARALLEL......................................................................................................... 45
Slysel ..................................................................................................... 45
Chapter 7: Best Efficiency Point ................................................. 47 Optimal Efficiency ..................................................................................... 47 Radial Load .............................................................................................. 47 Axial Load ............................................................................................... 48
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Slurry Pump Fundamentals
Shaft Deflection ........................................................................................ 49 Water Hammer ......................................................................................... 49
Chapter 8: Technical Descriptions .............................................. 51 Metal Pumps ............................................................................................ 51 LCC METAL SERIES (LCC-M) ................................................................................................ 51 FEATURES ............................................................................................................... 52 APPLICATION ........................................................................................................... 52 SIZE RANGE ............................................................................................................. 52 LSA-S SERIES .................................................................................................................. 52 FEATURES ............................................................................................................... 52 APPLICATION ........................................................................................................... 53 SIZE RANGE ............................................................................................................. 53
Rubber Pumps .......................................................................................... 53 LCC RUBBER-LINED SERIES (LCC-R)....................................................................................... 53 FEATURES ............................................................................................................... 54 APPLICATION ........................................................................................................... 54 SIZE RANGE ............................................................................................................. 54 LSR HEAVY-DUTY RUBBER-LINED SERIES ................................................................................ 54 FEATURES ............................................................................................................... 54 APPLICATION ........................................................................................................... 55 SIZE RANGE ............................................................................................................. 55
Vertical Pumps ......................................................................................... 55 LCV SERIES .................................................................................................................... 55 FEATURES ............................................................................................................... 55 APPLICATIONS .......................................................................................................... 56 SIZE RANGE ............................................................................................................. 56
High-Pressure, Multi-Stage Slurry pumps ......................................................... 56 WBC ............................................................................................................................ 56 FEATURES ............................................................................................................... 56 APPLICATIONS .......................................................................................................... 56 SIZE RANGE ............................................................................................................. 56 TBC ............................................................................................................................. 57 FEATURES ............................................................................................................... 57 APPLICATIONS .......................................................................................................... 57 SIZE RANGE ............................................................................................................. 58
Flue Gas Desulfurization Pumps (FGD) ............................................................ 58 FEATURES ............................................................................................................... 58 APPLICATION ........................................................................................................... 58 SIZE RANGE ............................................................................................................. 58
Chapter 9: Application Guide .................................................... 61 Selection by Duty ...................................................................................... 61 CLASSIFYING SLURRY ........................................................................................................ 61 GIW’S SERVICE CLASS CHART .............................................................................................. 62 GIW’S OPERATING LIMITS CHART ......................................................................................... 62
Guidelines for Selection by Duty ................................................................... 63 COARSE PARTICLES .......................................................................................................... 63 FINE PARTICLES .............................................................................................................. 63 SHARP (ABRASIVE) PARTICLES ............................................................................................. 63 HIGH PERCENT SOLIDS ...................................................................................................... 63 LOW PERCENT SOLIDS ...................................................................................................... 63 FIBROUS PARTICLES ......................................................................................................... 63
Duties Related to Head and Volume ............................................................... 64
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HIGH HEAD .................................................................................................................... 64 VARYING HEAD AT CONSTANT FLOW ..................................................................................... 64 VARYING FLOW AT CONSTANT HEAD ..................................................................................... 64 HIGH SUCTION LIFT.......................................................................................................... 64 HIGH FLOW ................................................................................................................... 64 LOW FLOW .................................................................................................................... 64 FLUCTUATING FLOW ........................................................................................................ 65
Duties Related to Slurry Type ....................................................................... 65 FRAGILE SLURRIES ........................................................................................................... 65 HYDROCARBON SLURRIES (OIL AND REAGENTS CONTAMINATED) ................................................... 65 HIGH TEMPERATURES ABOVE 212˚F (100˚C) SLURRIES .............................................................. 65 HAZARDOUS SLURRIES ...................................................................................................... 65 CORROSIVE SLURRIES (LOW PH) .......................................................................................... 65 HIGH VISCOSITY FLUIDS (NEWTONIAN) .................................................................................. 66 HIGH VISCOSITY FLUIDS (NON-NEWTONIAN) ............................................................................ 66
Selection by Industrial Application................................................................. 66 HARD ROCK MINING ......................................................................................................... 67 OIL SANDS ..................................................................................................................... 67 PHOSPHATE ................................................................................................................... 67 FGD ............................................................................................................................. 67 INDUSTRIAL PROCESS ....................................................................................................... 67
Chapter 10: Computerized Pump Selection ................................... 69 Slysel ..................................................................................................... 69 SOFTWARE AND HARDWARE REQUIREMENTS ........................................................................... 70 ORDER INFORMATION ....................................................................................................... 70
Chapter 11: General Maintenance .............................................. 71 Maintenance ............................................................................................ 71 RECOMMENDED MAINTENANCE SCHEDULE .............................................................................. 71 DAILY ........................................................................................................................... 71 WEEKLY ........................................................................................................................ 72 QUARTERLY ................................................................................................................... 72 SEMI-ANNUALLY .............................................................................................................. 72
Impeller Removal ...................................................................................... 72 IMPELLER BALANCING ....................................................................................................... 73
Fastener Torque........................................................................................ 74 TORQUE ACCURACY ......................................................................................................... 74 TORQUE CHARTS ....................................................................................................... 74
Mechanical Seals ....................................................................................... 74 Bearing Temperatures ...................................................................... .......... 75 LUBRICATION – OIL OR GREASE? .......................................................................................... 76 CAUSES OF BEARING FAILURES............................................................................................ 77
Vents and Breathers................................................................................... 78
Chapter 12: Total Cost of Ownership ........................................... 81 Importance of Making Smart Pump Purchases ................................................... 81 How GIW Can Help ..................................................................................... 82 Predicting Wear ........................................................................................ 82 Calculating Energy Costs ............................................................................. 83
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Chapter 13: Troubleshooting ..................................................... 85 Why Isn’t My Pump Pumping Correctly? ................................................ .......... 85 Warnings ................................................................................................. 85 EXCESSIVE PUMP DISCHARGE PRESSURE .......................................................................... 85 EXCESSIVE LEAKAGE AT SHAFT SEAL .............................................................................. 85 PUMP DELIVERS INSUFFICIENT FLOW RATE ....................................................................... 85 INCREASE IN BEARING TEMPERATURE.............................................................................. 86 BEARING CONTAMINATION ........................................................................................... 86 HIGH TEMPERATURE OR LEAKAGE AT THE STUFFING BOX ..................................................... 86 OVERHEATING OF PUMP CASING .................................................................................... 87 PUMP CASING LEAKS .................................................................................................. 87 PUMP FLANGE LEAKS ................................................................................................. 87 MOTOR OVERLOAD .................................................................................................... 87 VIBRATIONS OR ABNORMAL NOISES ................................................................................ 88
Help Is Here ............................................................................................. 88
Chapter 14: Appendix ............................................................. 91 Temperature Conversion Chart ..................................................................... 91 Mass Conversion Chart ................................................................................ 91 Velocity Conversion Chart ........................................................................... 91 Flow Conversion Chart ............................................................................... 92 Volume Conversion Chart ............................................................................ 92 Length and Distance Conversion Chart ............................................................ 93 Pump Duty Information Sheet ....................................................................... 94
Chapter 15: Glossary ............................................................... 95
Chapter 16: References ......................................................... 101 Chapter 17: Where It All Comes Together ................................... 103 Capabilities ........................................................................................... 103 TESTING AND DEVELOPMENT ............................................................................................ DESIGN ENGINEERING ..................................................................................................... MANUFACTURING .......................................................................................................... PRODUCTS...................................................................................................................
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History ................................................................................................. 105 Parent Company ..................................................................................... 105 How To Contact GIW............................ ..................................................... 106 GIW INDUSTRIES ............................................................................................................ 106 SERVICE CENTERS .......................................................................................................... 106 GIW REGEN SERVICE CENTER ...................................................................................... 106 GIW FLORIDA SERVICE CENTER ................................................................................... 106 FT. MCMURRAY SERVICE CENTER ................................................................................. 106
Chapter 1: What Is Slurry?
Chapter 1:
What Is Slurry? • Slurry is a mixture of something solid and a liquid. • The solids in a slurry can be anything from gold to gravel, copper to coal, sand to cement. They can also be crystalline, sharp, flaky, fibrous or frothy. • Almost any solid can be transported hydraulically via a slurry pipeline using a slurry pump. • Clear water is the primary liquid for slurry transport, but other liquids such as acids, alcohol and light petroleum have been used. In the mining industry, slurry pumps are used to transport slurries. The production of fertilizer, for example, involves massive slurry transport operations. To make the fertilizer, phosphate matrix is recovered by draglines in open-pit mining operations. (Draglines are huge electrically powered excavating machines with buckets that hold as much as 150 tons.) The matrix is then slurried (mixed with water) and pumped to the wash plant through pipelines with a typical length of six to 10 miles.
See Applications of Slurry Transport in “Slurry Transport Using Centrifugal Pumps.”
Slurry Pumps vs. Water Pumps Slurry pumps can be massive and often have replaceable wear parts. They are usually much heavier and larger than clear water pumps sized for the same head and flow. Some of the reasons for their larger size are:
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Slurry Pump Fundamentals
• Slurry pumps are constructed of special materials because of the abrasive nature of most slurries. These materials often require special bolting and assembly arrangements. • Slurry pump components are normally thicker than components for water pumps. • Slurry pump shafts and bearings are often larger than those on water pumps, because slurry Slurry pumps, like the one shown above, pumps handle various are usually much larger than water pumps. sizes and concentrations of solids. • Slurry pumps require larger impeller diameters to produce the same head because they usually run slower than water pumps to keep the wear within reasonable limits. • Slurry pumps may have large internal passageways because they often pass large solids. Water pumps account for the largest percentage of pumps installed in the process industry. For every five slurry pumps, 95 water pumps are in operation. The purchase and operating costs of a slurry pump are often many times that of a standard water pump. (Some industry experts put the operating costs of slurry pumps compared to those of water pumps at 80:20.) This is why the correct selection and application of your slurry pump is essential to your operation’s efficiency. Flow Limitations
The flow limitations for a slurry pump installation are from 35 - 132,000 gpm (8 - 30000 m3/hour).
Chapter 1: What Is Slurry?
These limits are determined by the pump’s ability to withstand the forces associated with operating the pump, such as pressure, vibration, axial thrust and the stability of the pump at various flows.
See Basic Relations for Flow of Simple Fluids in “Slurry Transport Using Centrifugal Pumps.”
Solids Limitations
Theoretically, there are no limits on what can be hydrotransported. In practice, however, the size and shape of the solids limit what can be pumped because of the risk of the solids blocking passage through the pump. The maximum particle size of material that can be transported in a slurry pump is approximately 12 inches (300 mm). However, sphere passage in large dredge pumps can be up to 18 inches (450 mm).
The solids transported in this dredging operation were as large as a hard hat.
See Basic Relations for Slurry Flow in “Slurry Transport Using Centrifugal Pumps.”
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