Tump User's handbook. Life 'Extension. 4th Edition. <By. 'Heinz?. *B(och & Man H Quarts. CRC Press. Taylor& Francis Group THE FAIRMONT PRESS, INC.

Transcription

1 Tump User's handbook Life 'Extension 4th Edition <By 'Heinz?. *B(och & Man H Quarts W THE FAIRMONT PRESS, INC. CRC Press Taylor& Francis Group

2 Ta^fe of Contents Preface to the Fourth Edition xi Acknowledgements xiii Chapter 1 PUMP SYSTEM LIFE CYCLE COST REDUCTION 1 Chapter 2 Initial Costs 2 Installation Costs 2 Energy/Operating Costs 2 Maintenance and Repair Costs 2 Loss of Production 3 Pump Reliability Factors 3 HOW TO BUY AND SHIP A BETTER PUMP 5 Specification Overview 5 ANSI vs. API How do They Differ? 5 Process Industry Practices (PIP) 8 Supplementary Specifications 8 Specification Checklists 9 Selecting a Knowledgeable Cooperative Vendor 10 Design Weaknesses Found in API Casing Construction 13 Bearing Housing Designs Merit Closer Attention 14 Upgrading of Centrifugal Pumps 18 Excessive Shaft Deflection 18 Factors Affecting Bearing Life 20 Documentation is Part of Initial Purchase 23 Bid Tabulations Lead to Final Selection 26 How to Ship Pump Sets 30 Chapter 3 PIPING, BASEPLATE, INSTALLATION, AND FOUNDATION ISSUES 35 Pump Piping. 35 Field Installation Procedure for Pipe Spring Hangers and Pipe Supports 40 Pump Baseplates and Grouting 44 Pump Alignment 64 Pump Suction Strainers 76 Eccentric Reducers and Straight Runs of Pipe at Pump Suction 79 Chapter 4 OPERATING EFFICIENCY IMPROVEMENT CONSIDERATIONS 81 Total System Efficiency 81 Energy Energy Operating Cost Savings Effectiveness 81 Potential 82 V

3 Chapter 5 System Efficiency 84 Creating Pump/System Head-Capacity Curves 91 Parallel Pump Operation 93 Additional Reliability Issues withparallel Operation 94 Specific Parallel Pump Guidelines/Process Pumps 95 Impact of Variable Speed Control on Parallel Pump Operation 96 Multi-Pump Parallel Operation Control 96 Parallel Pump Operations Conclusions 97 Grounding Ring Technology for Variable Frequency Drives (VFDs) 99 How to Optimize the Overall Ill Efficiency When Pumps are Operated as Both Pumps and Power Recovery Turbines in the Same System Ill Understanding Periodic Switching of Process Pumps and Power Recovery Turbines 113 IMPROVED PUMP HYDRAULIC SELECTION EXTENDS PUMP LIFE 115 Chapter 6 Influence of Pump Hydraulic Selection 115 Operating Speed 115 Allowable Operating Region 116 Suction Recirculation 116 Mitigating Suction Recirculation Problems 118 Suction Energy 119 NPSH Margin 121 NPSH Margin Reliability Factor 123 Total Pump Hydraulic Relative Reliability 125 Pump Reliability Impact from System Design 126 Pump Sump Intake Design 126 Water Hammer 126 IMPROVEMENTS LEADING TO PUMP MECHANICAL MAINTENANCE COST REDUCTION 129 Chapter 7 Mechanical Maintenance Life Cycle Impact 129 Pump Reliability Reviews Start Before Purchase 129 Mean-Time-Between-Failure Calculations 130 "ANSI Plus " Mechanical Seal Gland 133 Sealed Power Ends and Expansion Chambers 133 Bearing Housing Seals in the Lubrication Environment 137 Dual-Face Magnetic Bearing Housing Seals 140 Features of Upgraded Centrifugal Pumps 144 Advanced Lubrication Strategies 145 Telescoping Shaft Seal Sleeve 146 Dynamic Shaft Seal an Occasional Alternative to the Mechanical Seal 146 Consider Composite Materials in Centrifugal Pump Wear Components 148 BEARINGS IN CENTRIFUGAL PUMPS 151 Pump Bearing Loads ; 151 Radial Load 153 vi

4 Bearing Types Used in Centrifugal Pumps 154 Pump Bearing Arrangements 155 Bearing Life 156 Bearing Lubrication 158 Oil-Bath Lubrication 162 Oil Ring Lubrication 163 Oil Mist Lubrication Overview 164 Grease Lubrication Overview 164 Bearing Temperature 165 Bearing Mounting and Radial Clearance 166 Housing Fits 167 Internal Radial Clearance 169 Bearing Housing Sealing 169 Angular Contact Ball Bearings in Centrifugal Pumps 169 Bearing Preload 171 Universally Matchable Single Row Angular Contact Ball Bearings 172 Cages 174 Recommended Bearing Applications Summarized 175 MRC Pumpac Bearings 175 Double-Row Angular Contact Ball Bearings 177 Double-Row Angular Contact Bearings with Two Inner Rings 178 Roller Bearings in Centrifugal Pumps 180 Sliding Bearings 182 Pivoted Shoe Thrust Bearings 182 Parameters Related to Pivoted Shoe Bearings 185 End-Play and Radial Clearance 186 Preload 186 Lubrication 186 Operation and Monitoring 188 Bearing Housing Protection 189 Chapter 8 MECHANICAL SEAL SELECTION AND APPLICATION 191 Design of Mechanical Seals 191 Types of Seals 191 Seal Face Lubrication Enhancements Employing Laser... Etching Technology 201 Seal Flush and Environmental Control Plans 206 Reliability Improvement in Mechanical Seals Analysis of Design Considerations 207 Basic Considerations for Seal Users and Manufacturers 215 Designing for Decreased Failure Risk 227 Case Studies Involving Enhancing the Seal Environment by Using Conversion from and to Different Seal Plans 228 Advanced Flow Inducers and Bi-directional Internal Pump-around Devices 236 Phasing Out Pump Packing 237 Dual Mechanical Seal Designs and API Comparison of Different Dual Seal Arrangements 240 More Mechanical Seal Case Studies 245 What to Look for in Strategic Mechanical Seal Partnerships 246 vii

5 Chapter 9 IMPROVED LUBRICATION AND LUBRICANT APPLICATION 251 Extending Pump Life by Understanding Lube Application 251 Synthetic Lube Overview 259 Balanced Constant Level Lubricators: How Cost-Effective? 268 Splash Lubrication, Oil Rings and Flinger Discs 269 Why and How to Protect Bearings Against Lube Contamination-Related Failures 275 Lubricants, Base Stocks and Performance Tradeoffs 298 Lubricants, Tests and Properties 300 Lubricants and the Importance of Clean Products 302 Chapter 10 OIL MIST LUBRICATION AND STORAGE PROTECTION 305 System Usage 306 "Purge Mist," or "Wet Sump" Oil Mist 307 Dry Sump Oil Mist is Advantageous 308 Modern Plant-Wide Systems Enhance Safety and Reliability 310 Environmental Concerns Addressed 311 Economics of Dry Sump Oil Mist Lubrication 312 Selecting the Correct Oil 313 Oil Mist for Electric Motors 313 Electric Motor Codes and Practices 323 On the Safety of Explosion-Proof Motors for Class 1 Division 1 Service 325 Long-term Storage of Pumps and Motors Using Oil Mist 326 Chapter 11 COUPLING SELECTION GUIDELINES 333 Coupling Function 333 Rigid Couplings 334 Flexible Couplings 336 Couplings for Centrifugal Pumps 341 Chapter 12 PUMP CONDITION MONITORING GUIDELINES 343 Vibration Basics 343 Predictive Condition Monitoring and Fault Tolerant Intelligent Drives/Controls 347 Rotor Balancing 347 Vibration Acceptance Limits 349 Causes of Excessive Vibration 350 Chapter 13 PUMP TYPES AND MATERIALS 363 Petroleum Refinery Service Pumps (API-610) 363 API-610 Materials of Construction and Grade Levels 368 Magnetic Drive and Positive Displacement Pumps 369 Chemical Pumps 369 viii

6 Chapter 14 Key Selection Criteria for Chemical Applications 369 Canned Motor Pumps Make Important Inroads in Refinery Servces 372 Paper Stock and Other Large Process Pumps 374 Double Suction/Axially Split Case Pumps 378 Sewage and Waste Water Submersible Pumps (Solids and Non-clog) 379 Slurry Pumps 381 Vertical Column Turbine ("VTP") Pumps 383 Bowl Assembly 384 Vertical Enclosed Shaft-Driven 386 Recessed Impeller Sump Pumps 386 Bearing Materials 390 Column Assembly 392 Critical Speed 392 Discharge Head Assembly 394 Sump Design 395 Split Flow Centrifugal Pumps 395 Modern Pumps Have Stiffer Shafts 397 Typical Pump Material Selection 398 PUMP FAILURE ANALYSIS AND TROUBLESHOOTING 403 Chapter 15 Organizing Systematic Pump Failure Reduction Programs 403 SHOP REPAIR, SPARE PARTS AVAILABILITY & PROCUREMENT 439 Chapter 16 Shop Repair Procedures 442 Moving from Repair-Focus to Reliability-Focus 454 Combining Pump Maintenance with Systematic Pump Upgrading 457 FAILURE STATISTICS AND COMPONENT UPTIME IMPROVEMENT SUMMARY Chapter 17 Pump MTBF as a Function of Component MTBF 469 Examining Pump Repair Records and MTBF 470 Gordon Buck's Study of Pump Statistics 470 Seal Mtbf Explored 472 MTBF Simulations and Seal MTBF Levels Currently Being Achieved 473 Target Pump and Component Lifetimes 475 How Competent Manufacturers Improve Component Reliability 476 Couplings 476 Bearings 477 Supplier/Customer Relationships 479 BREAKING THE CYCLE OF PUMP REPAIRS 483 Examining the Cost of Failures 483 Pumps Have a Defined Operating Range 484 Getting into Mechanical Issues 485 Deviations from Best Available Technology 486 More on Lubrication and Bearing Distress 488 Two Different DN-rules Explained 489 ix

7 The Trouble with Oil Rings and Constant Level Lubricators 490 Bearing Housing Protector Seals 493 Ranking the Different Lube Application Practices 494 Demand Better Pumps and Pay for Value 497 Appendix 1 PUMP START-UP AND SHUTDOWN PROCEDURES 499 Appendix 2 A "HUNDRED-PLUS POINTS" SUMMARY OF PUMP RELIABILITY IMPROVEMENT OPTIONS AND CONSIDERATIONS 501 Appendix 3 SUPPLEMENTARY SPECIFICATION FOR API-CLASS PUMPS 508 Appendix 4 SPECIFICATION AND INSTALLATION OF PRE-GROUTED PUMP BASEPLATES Appendix 5 PROTECTION OF MECHANICAL SEALS IN NON-OPERATING PUMPS 524 Appendix 6 EXPLAINING THE INGRESS PROTECTION CODE 525 References 527 Index 539 X