راهنمای میدانی انتخاب و عیب‌یابی پمپ (راهنماهای میدانی AWWA)

Pumps are the most expensive part of a water system to operate and can be very expensive to repair or replace after a failure. Proper pump selection and operation is essential for long service life. This handbook is specially written to provide operators, engineers, and maintenance staff with a quick reference on selecting, operating, troubleshooting, and maintaining all types of pumps. Front Matter 1 List of Figures 3 Abbreviations/Definitions 5 Table of Contents 6 Introduction 8 1. Pump Horsepower 10 1.1 Introduction 10 1.2 Performance 10 1.3 Static Head 11 1.4 Friction Loss 11 1.5 Horsepower Definitions and Calculations 14 1.6 Motor Horsepower Actual 15 1.7 Example Problems 17 Summary 19 2. Pump Types 20 2.1 Introduction 20 2.1.1 System Requirements 20 2.1.2 Net Positive Suction Head NPSH 21 2.1.2.1 Suction Side Pressure 22 2.1.2.2 Pump Efficiency Factors 22 2.1.2.3 Motor Efficiency 23 2.1.2.4 Replacement Evaluation 23 2.2 Centrifugal Pump Types 23 2.3 Centrifugal Pump Selection 29 2.3.1 Efficiency 30 2.3.2 Motor Size 30 2.3.2.1 Brake Horsepower 30 2.3.2.2 Nonoverloading across the Range 32 2.3.3 Pump Curve Shape 32 2.3.4 Pressure/Flow Relationship 33 3. Flow Variations 34 3.1 Introduction 34 3.1.1 Pump Operation 34 3.1.2 Redundancy 34 3.1.3 Sizing Strategies 34 3.1.4 Multiple Pumps 35 3.2 Throttling 35 3.2.1 Increasing Pressure 37 3.2.2 Effects of Reduced Pressure 37 3.2.3 Increased NPSHR 38 3.2.4 Seasonal Variations 38 3.3 Variable-Speed-Drive Systems 39 3.3.1 Variable-Frequency Drives VFDs 39 3.3.2 Variable-Speed Pump Calculations 39 3.3.3 VFD Design 40 3.3.4 Actual Pump Curves 41 3.3.5 Low Speed Operating Point 41 3.3.6 High-Speed Operating Point 43 3.3.7 System Head Loss Remains the Same or Nearly So 43 3.3.8 Comparison of Operating Conditions 44 3.3.9 Benefits of a VFD System 44 3.3.10 VFD Design Considerations 45 3.3.11 Pump Efficiency Factors 46 3.3.12 Motor Efficiency 46 3.3.13 Replacement Evaluation 46 3.4 Pump Capacity Options 46 3.4.1 System Size 47 3.4.2 Present versus Future Demand 47 3.4.3 Variations in System Demand 47 3.4.4 Water System Optimization 48 Summary 48 4. Pump Troubleshooting 49 4.1 Introduction 49 4.2 Close Coupled Centrifugal Pumps 49 4.2.1 Preliminary Evaluation 49 4.2.2 Flowmeter 50 4.2.3 Pressure Boost 51 4.2.4 Design Conditions 51 4.2.5 Low Flow/Pressure 51 4.3 Frame-Mounted Centrifugal Pumps 53 4.3.1 Seals 54 4.3.2 Vibration Pump or Motor 55 4.4 Vertical In-Line Centrifugal Pumps 55 4.5 Vertical Line Shaft Turbine Pumps 55 4.5.1 Inadequate Submergence 55 4.5.2 Application Issues 56 4.5.3 Pipe Column 57 4.6 Wet Well Design 58 4.7 Submersible Pumps 58 4.7.1 Well Pumps 58 4.7.2 Submersible Solids-Handling Pumps 59 4.8 Maintenance 60 4.8.1 Scheduled Maintenance 60 4.8.2 Crisis Management 60 4.9 Recommendations 61 4.9.1 On-Site Records 61 4.9.2 Maintenance Chart 61 4.9.3 Records 61 4.9.4 Use of the Maintenance Manual 61 4.9.5 System-Wide Operation and Maintenance Plan or Implementing a Green System 62 5. Chemical Pumps 63 5.1 Introduction 63 5.2 Pump Types 63 5.2.1 Diaphragm Pumps 63 5.2.2 Peristaltic Pumps 70 5.2.3 Progressive Cavity Pumps 71 5.3 Accessories 71 5.3.1 Tanks 72 5.3.2 Mixers 72 5.3.3 Valves 73 5.3.4 Calibration Chambers 74 5.3.5 Pulsation Dampeners Surge Suppressors 74 5.3.6 Gauge Isolators Not Shown 74 5.3.7 Flow Sensors 75 5.3.8 Flowmeters 75 5.3.9 Flushing Systems 75 5.3.10 Injection Quills 77 5.3.11 Flash Mixing 77 5.3.12 Materials of Construction 78 5.3.13 Containment/Storage 78 5.4 Pump Rate Calculations 78 5.4.1 Diaphragm Pumps 78 5.4.2 Minimum and Maximum Rates 79 5.4.3 Sample Chemical Pump Sizing Calculations 79 5.4.4 Recommendation 80 6. Operation and Maintenance Manual 81 6.1 On-Site Records 81 6.1.1 Process Pumps 81 6.1.2 Chemical Pumps 81 6.1.3 Maintenance Requirements 82 6.1.4 Spare Parts 82 6.2 Accessories 82 6.3 Written Procedure 82 Appendix: Chemical Resistance Chart 83 Index 91 A 91 B 91 C 91 D 95 E 96 F 97 H 99 I 99 J 99 M 100 N 100 O 101 P 102 Q 104 R 104 S 104 T 105 V 106 W 109 Pumps are the most expensive part of a water system to operate and can be very expensive to repair or replace after a failure. Proper pump selection and operation is essential for long service life. This handbook is specially written to provide operators, engineers, and maintenance staff quick and easy methods to determine whether a pump is operating properly Content: Front Matter • List of Figures • Abbreviations/Definitions • Table of Contents • Introduction 1. Pump Horsepower 2. Pump Types 3. Flow Variations 4. Pump Troubleshooting 5. Chemical Pumps 6. Operation and Maintenance Manual • Appendix: Chemical Resistance Chart Index Choose the right pumps for the job and keep them working smoothly with this handy field guide.