ABSTRACT
Finding the Important Tables 167 Sensor and Loop Accuracy 167
Accuracy Is a Percent of What? 168 Rangeability 169 Accuracy and Rangeability 170
Reynolds Number 173 Flowmeter Selection 176 Suitability for Different Applications 176
Viscous Fluids 176 Slurry and Fibrous Fluids 177 Abrasive and Corrosive Fluids 178 Pressure and Temperature Ratings 178 Pulsating Flows 180 Multiphase Flow Metering 180 Bidirectional Flows 180 Semi lled Pipes and Open Channels 181 Low-Flow Applications 182 Straight Pipe Run Requirements 182 Pressure Loss through Flowmeters 183
Example 184 Flowmeter Types 184
Head Type Meters 184 Mass Flowmeters 191 Calibration, Provers 193 Safety 194 Installation 194 Cost 194
Conversion among Flow Units 195 Effect of Reynolds Numbers and Diameter
Ratios on Discharge Coef cients 196
Selection Recommendation Tables from Other Sources 197
Selection Tables and Speci cation Form 197 Bibliography 204
2.2 APPLICATIONS: ABRASIVE, CORROSIVE, SLURRY 205
Introduction 205 Abrasive or Erosive Service Flowmeters 205
Conclusions 207 Corrosive Services 207
Conclusion 208 Slurry and Sludge Services 208
Conclusion 208 Viscous Services 209
Conclusion 210 Bibliography 210
2.3 APPLICATIONS: BIDIRECTIONAL FLOWMETERS 211
Introduction 213 Measurement Methods 213
Magnetic Meters 213 Coriolis Meters 214 Thermal Meters 214 Ori ce Meter 214 Annubar Meters 215 Wedge Type Flowmeter 215
Turbine Meters 215 Ultrasonic Meters 216 Venturi Meters 216 Bidirection by Piping 217 Calibration 218 Meter Health 218 Roles of Responsible Parties 218
Speci cation Forms 218 Abbreviations 220 Organizations 220 Bibliography 220
2.4 APPLICATIONS: MULTIPHASE AND SUBSEA FLOWMETERS 221
Introduction 222 Wet-Gas Metering 222
Venturi Meters 223 Algorithms for Wet-Gas Measurement 223 Theory of Operation of Wet-Gas
Metering 223 de Leeuw Wet-Gas Venturi Correlation 223 Liquid Mass Flow Rate Correction
Algorithm 224 Liquid Density Calculation Algorithm 224 Upstream Temperature Correction and
Pressure Recovery 225 Gas Mass Fraction Estimation Using
Tracer Techniques 225 Solartron-ISA Dualstream II™ Theory 225
Multiphase Flowmeters 226 Subsea Downhole Flowmeter 228 Types of Downhole Flowmeters 229
Venturi Meter 229 Fiber-Optic Measurement of Flow,
Pressure, and Temperature 229 Uncertainty Issues and Limitations with
Downhole Meters 232 Conclusion 232 Speci cation Form 232 De nitions 234 Abbreviations 234 Organizations 234 Bibliography 234
2.5 APPLICATIONS: MULTIPHASE HYDROCARBON METERING 235
Introduction 236 Reasons for Using Multiphase Measurement 237
Production Tank Separator 237 Well Test Separator 237
Using Venturi Meters 239 Ultrasonic Measurement Method 241 Coriolis Flowmeter-Based Multiphase
Measurement 241 Calibration Multiphase Flowmeters 242 Smart Meters 243
Conclusions 243 Speci cation Form 243 De nitions 245 Abbreviations 245 Bibliography 245
2.6 CALIBRATION AND MAINTENANCE 246
Introduction 247 Basic Principles 248
Traceability 248 Build the Metering System 248
Meter Proving 248 Standard Conditions De ned 250
Proving of Liquids 252 Tank Proving 252 Bidirectional or Unidirectional Proving 253
Proving of Gases 254 Bell Prover 254 Piston Prover 254 Sonic Nozzle Prover 255
Master Metering 256 Flow Computers 257 Mathematical Meter Validation 257 Factory Recalibration 257 Proving the Prover 258 Frequency of Proving 258 Maintenance Considerations 258 Conclusions 259 De nitions 259 Abbreviations 259 Organizations 259 Standards 260 Bibliography 260
2.7 INSTALLATION 261
Introduction 262 Process Containment and Safety 262
Installation 262 Preferred Installation 262 Liquid Flow 262 Liquid Level 263 Gas Flow 263 Steam Flow 264
Components 265 Impulse Lines 265 Impulse Line Size 265
Freeze Protection 265 Resonance in Impulse Lines 265
Process Connections 266 Fabricated Manifold 266
Flow Element Installation 266 Ori ce Meter 266
Manufactured Manifold 268 Remote Diaphragm Seals 268 Recent Developments 268 De nitions 268 Abbreviations 269 Institutions, Societies 269 Standards 269 Bibliography 269
2.8 ANEMOMETERS 270
Mechanical Anemometers 271 Pitot Tubes 272
Thermal Anemometers 272 Ultrasonic Anemometers 273
Acoustic Resonance Anemometer 273 Doppler Anemometers 274 Aviation Applications 275 Conclusion 276 Speci cation Form 276 Abbreviations 278 Bibliography 278
2.9 BTU FLOW MEASUREMENT: FUEL GAS 279
Introduction 280 Measuring Heat Flow by the Wobbe Index
(WI) 281 BTU Flowmeter Loop 281 Applications 282 Conclusion 282 De nitions 282 Abbreviations 283 Organization 283 Bibliography 283
2.10 BTU FLOW MEASUREMENT: LIQUIDS 284
Introduction 284 BTU Flow in Homes and Of ce Buildings 284 Industrial BTU Flowmetering 285 Mechanical BTU Meters Used in HVAC
Applications 286 Industrial Process Applications 287 Speci cation Form 287 Abbreviations 289 Bibliography 289
2.11 CROSS-CORRELATION FLOWMETERING 290
Introduction 291 Determining the Transit Time 291 Reliability and Accuracy 292
Cross-Correlation Flowmeter Designs 293 Ultrasonic Cross-Correlation Flowmeters 293 Partially Filled Pipes and Channels 294 Hot Gas Flow Measurement 294
Nuclear Power Plant Applications 294 TTFM System 295
Speci cation Form 297 Abbreviations 298 Bibliography 298
2.12 ELBOW FLOWMETERS 299
Introduction 299 d/p Meters Using Elbows as the Flow Element 300 Location and Size of Taps 301 Transmitters 302 Other Centrifugal Force Based Flowmeters 302 Sand Flow Monitors 303 Speci cation Form 303 De nitions 305 Bibliography 305
2.13 FLOW SWITCHES 306
Introduction 309 New Developments 309
Paddle Switches 310 Thermal 311
Solids Flow Switches 313 Installation Considerations 313 Speci cation Forms 313 Bibliography 316
2.14 LAMINAR FLOWMETERS 317
Introduction 317 Theory 318
Hagen-Poiseuille Law 319 Design Parameters 319 Design Calculations for Liquid Service 320
Error Sources 320 Range Extension Techniques 321 Commercially Available Units 323 Conclusion 323 Speci ction Form 323 Abbreviations 325 Organizations 325 Bibliography 325
2.15 MAGNETIC FLOWMETERS 326
Introduction 327 Theory 327
Advantages 329 Limitations 329
Types of Magnetic Flowmeters 330 AC Magnetic Flowmeters 331 DC Magnetic Flowmeters 332 Dual-Frequency Excitation 333 Other Types 333
Wireless Flowmeters 333 Construction of Magnetic Flowmeters 334
Ceramic Liners 335 Probe-Type Units 336
Applications of Magnetic Flowmeters 336 Accuracy and Calibration 338 Errors in Magnetic Flowmeters 339
Effects of Electrical Conductivity of Fluid 340 Installation 341 Signal Considerations and Demodulation
Techniques 342 Recent Progress in Electromagnetic
Flowmeters 343 Speci cation Form 343 Abbreviations 345 Organization 345 Bibliography 345
2.16 MASS FLOWMETERS: CORIOLIS 346
Measuring Principle and Theory 347 Principle 347 Theory 348
Design of Coriolis Mass Flowmeter 349 Balancing Systems for Coriolis Mass
Flowmeter 349 Dual-Tube and Four-Tube Meters 350 Single-Tube Meters 350 Tube Geometries 351 Sensors 352
Temperature Sensors 352 Security 352 Electronics and Signal Processing 353 Communication/Output 353
Technical Data 354 Measuring Accuracy/Range 354 Gas Measurements 354 Viscosity Measurement 354 Pressure Drop 354 Two-Component Flow 354 Wet Gas 355 Dynamic Response 355 Power Supply 355
In¨uences on the Coriolis Mass Flowmeter Reading 355
Temperature 355 In-Line Pressure 355 Vibration 356 Corrosion and Erosion 356 Humidity 356 Fluid Velocity 356 Flow Pro le Effects 356 Reynolds Number Effect 357
Installation 357 Mechanical Installation 357 Up-or Downstream Straight Pipe Run 357 Zero-Point Adjustment (Static/Dynamic) 357 Recalibration/Maintenance 358 Mounting 358
Applications 358 Oil/Gas Production/Custody Transfer 359
Advantages of Coriolis Mass Flowmeters 359 Limitations of Coriolis Mass Flowmeters 360 Speci cation Form 360 De nition 362 Bibliography 362
2.17 MASS FLOWMETERS: INDIRECT AND TURBINE 364
Indirect Mass Flow Detection 364 Volumetric Flow and Density 365
Mass Flow of Steam 365 Example 366
Angular Momentum-Type Mass Flowmeters 366
Turbine-Type Mass Flowmeters 367 Constant Torque-Hysteresis Clutch 367 Twin-Turbine Flowmeters 367 Gyroscopic 368
Speci cation Form 368 Bibliography 370
2.18 MASS FLOWMETERS: THERMAL 371
Heat Transfer Flowmeters 373 Bypass-Type Designs 374
Hot-Wire Probes 375 Calibrating Thermal Mass Flow Devices 377
Gas Flowmeter Calibrations 377 Liquid Calibrations 378
New Developments 379 Speci cation Forms 381 Abbreviations 383 Organizations 383 Bibliography 383
2.19 METERING PUMPS 384
Peristaltic Pumps 387 Piston Pumps 388 Diaphragm Pumps 390
Hydraulic-Actuated Metering Pumps 390 Solenoid-Driven Metering Pumps 391 Pulsator-Head Pumps 392
Proportioning Pumps 392 Controllers 393
Pulse-Input Type 393 Analog-Input Type 393 Start/Stop Type 393
Conclusion 393 Bibliography 393
2.20 OIL-CUSTODY TRANSFER 394
Introduction 395 Components of a Custody Transfer System 396 Provers 398
Provers Design and Constructions 399 Master Meters 400
Automatic Sampling 401 Liquid Sampling 401 Gas Sampling 402
Custody Transfer Calculation Standards 403 Flow Equation Algorithms 405
General Volumetric Equation at Flowing Rate Condition 405
Flow Rate at Reference Conditions for Gas 406
Compressibility Factors 406 Liquid Volume Correction Factors 407 Instrumentation Calibration and Provers
Correction Factors 407 Energy Equivalency Estimation 407
Calculation Sampling and Average Methods 407 Auditing Logs Reporting and Security 408 Lease Automatic Custody Transfer (LACT)
Units 408 Abbreviations 410 Organizations 410 Standards 410 Bibliography 411
2.21 ORIFICES 412
Head-Type Flowmeters 414 Theory of Head Meters 414 Head Meter Characteristics 416 Reynolds Number 417
Compressible Fluid Flow 418 Choice of Differential Pressure Range 418 Pulsating Flow and Flow “Noise” 418
Ori ce Meter 419 Flow through the Ori ce Plate 420 Location of Pressure Taps 420
Eccentric and Segmental Ori ce Plates 422 Quadrant Edge and Conical Entrance Ori ce
Plates 423 Conditioning Ori ce 424 Integral Ori ce 424 Installation 424 Limitations 427 Ori ce Bore Calculations 428
Old Approach 428 Ori ce Accuracy 431 Advanced Designs 433 Speci cation Forms 434 De nition 436 Organizations 436 Bibliography 436
2.22 PADDLE FLOW SWITCHES 437
Application 438 Design 438
Operating Principle 438 Vane 439 Transducer 440 Switching Element 441
Installation Precautions 441 Speci cation Form 442 De nition 444 Abbreviations 444 Organizations 444 Bibliography 444
2.23 PITOT AND AREA-AVERAGING TUBES 445
Theory of Operation 447 Pressure Differential Produced 448 Static Pressure Measurement 448 Single-Ported Pitot Tube 449
Calibration of Pitot Tubes 451 Multiple-Opening Pitot Tubes 452
Averaging Tube Suited for Mass Flow Measurement 454
Combination of Pitot Tubes with Flow Nozzles 454
Area-Averaging Pitot Stations 455 Special Pitot Tubes for Pulsating Flow 456
Pitot Tube Applications in Aviation 457
Speci cation Form 458 Abbreviations 459 Bibliography 459
2.24 POSITIVE-DISPLACEMENT GAS METERS 460
History 461 Diaphragm Meter 461 Rotary Meters 463
Application Notes 464 Testing and Calibration 464
Conclusions 465 Speci cation Forms 465 Abbreviations 468 Bibliography 468
2.25 POSITIVE-DISPLACEMENT LIQUID METERS AND PROVERS 469
Overview 470 Rotating Lobe and Impeller (Type A) 471 Nutating Disk (Type B) 472 Oval-Gear Flowmeters (Type C) 472 Piston Designs (Type D) 474
Reciprocating Piston 474 Oscillating Piston 474
Miniature Oscillating Piston 475 Rotating Vane (Type E) 476 Viscous Helix (Type F) 476 High Precision and Specialized (Type G) 477 Provers (Type H) 477 Accessories and Intelligent Electronics 478 Speci cation Forms 478 Bibliography 481
2.26 PURGE FLOW REGULATORS 482
Detection of Low Flows 483 Purge Rotameters 483 Brazing and Welding Applications 484 Bibliography 485
2.27 SEGMENTAL WEDGE FLOWMETER 486
Design and Applications 487 Sizing and the Reynolds Number 487 Calibration 488 Summary 489 Speci cation Form 489 Bibliography 491
2.28 SIGHT FLOW INDICATORS 492
Design Variations 493 Dual-Window and Full-View Designs 495 Special Designs 497 Conclusion 497 Speci cation Form 498 Abbreviations 499 Organizations 499 Bibliography 499
2.29 SOLIDS FLOWMETER AND FEEDER 500
Solids-Handling Equipment 502 Hoppers and Accessories 503 Feeder Designs 504
Gravimetric Weigh Belt Feeders 507 Early Belt Feeder Designs 508 Feed Rate Control 509 Vertical Gravimetric Feeders 514
Loss-in-Weight Feeder 515 Continuous Operation 515 Equipment 516 System Sizing 516
Dual-Chamber Gravimetric Feeder 516 Dynamic Solids Flowmeters 517
Impact-Type Solids Flowmeter 517 Centripetal Force Solid Flowmeter 518 Accelerator-Type Flowmeter 518 Volumetric Flowmeters 520
Cross-Correlation Solids Flowmetering 520 Mass Flow Measurement of Pulverized Coal 522
Detecting Mass Concentration by Microwave 522
Measuring the Pulverized Coal Velocity 522 Noncontact Microwave Solid Flowmeter 523
Conclusion 523 Abbreviations 523 Bibliography 524
2.30 TARGET METERS 525
Introduction 526 Theory of Operation and Accuracy 526 Design Variations 527 Other Features 527 Calibration 528 Advantages and Limitations 528 Speci cation Form 528 Bibliography 530
2.31 TURBINE AND OTHER ROTARY ELEMENT FLOWMETERS 531
Linearity and Repeatability 533 Viscosity and Density Effects 534 Liquid Turbine Meters 535 Electronic Display Units 536
Meter Sizing 536 Special Applications 537
Turbine Flowmeter Features 538 Mechanical Installation 539
Electrical Installation 540 Gas Turbine Meters 540
History 541 Dual-Turbine Designs 543
Dual Turbines Rotating in the Same Direction 544
Dual Turbine with Counter-Opposed Rotation 544
Shunt Flowmeters 545 Impeller and Propeller Meters 546 Insertion-Type Flowmeters 547
Optical Flow Sensors 547 Paddlewheel Flowmeters 548
Pelton Wheel Meters 548 De nitions 548 Abbreviations 549 Bibliography 549
2.32 ULTRASONIC FLOWMETERS 550
History 551 Components 554 Theory of Operation 555
Time-of-Flight (TOF) or Transit-Time Ultrasonic Flowmeters 555
Open Channel Meters 557 TOF Design with Clamp-On Transducers 558 Doppler Design with Clamp-On
Transducers 559 Open Channel 559
Time-of-Flight/Pulsed Doppler, Acoustic Discharge Flowmeters 559
Installation Guidelines 561 Transmitters, Displays, and Intelligent
Units 561 Transducers 561
New Developments 561 Conclusion 563 Speci cation Form 563 De nitions 565 Abbreviations 565 Organizations 565 Further Readings 565
2.33 VARIABLE AREA, GAP, AND VANE FLOWMETERS 567
Rotameters 569 Sizing 571 Rotameter Characteristics 571 Rotameter Types 573 Bypass and Pitot Rotameters 574
Tapered Plug and Piston Meters 575 Gates and Vanes 576 De nitions 577 Abbreviations 577 Bibliography 577
2.34 VENTURI, PROPRIETARY TUBES, AND FLOW NOZZLES 578
Introduction 579 Capacity and Permanent Pressure Loss 579 Flow Calculations 580 Beta Ratio and Reynolds Numbers 580
Classic Venturi 582 Short-Form (Proprietary) Venturis 582
Installation 583 Sizes 584 Critical-Velocity Venturi Nozzles 584
Flow Tubes 584 Flow Nozzles 586
Flow Nozzle Installation 587 Accuracy 588 Differential Pressure Measurement 588 Conclusion 589 Speci cation Forms 589 De nitions 592 Abbreviations 592 Organization 592 Bibliography 592
2.35 VORTEX AND FLUIDIC FLOWMETERS 593
Vortex Shedding Phenomenon 594 Physical Geometry 595 Flow Tube 595 Detector 595
Features 596 Selection and Sizing 597 Installation Requirements 600
Vortex-Precession (Swirl) Meters 601 Fluidic (Coanda Effect) Meters 601
Characteristics 602 Conclusion 603 Speci cation Form 603 Bibliography 605
2.36 V-SHAPED CONE FLOW ELEMENTS 606
Introduction 607 Designs and Operation 607 Theory of Operation and Sizing 608
For Liquids 608 For Gas and Steam 608
Speci cation Form 609 Bibliography 611
2.37 WEIRS AND FLUMES FOR OPEN CHANNELS 612
Introduction 613 Weirs 613
Broad Crested Weirs 615 Flumes: The Parshall Flume 615
Palmer-Bowlus Flume 617 Parabolic and Leopold-Lagco Flumes 617 Kennison Nozzle 617 Open-Channel Flow Measurement 617 Intelligent Readouts 619 Conclusion 619 De nitions 619 Abbreviations 620 Organization 620 Bibliography 620
FINDING THE IMPORTANT TABLES
Table 2.1a (pp. 171-172): Flowmeter Accuracy and Rangeability
Table 2.1b (pp. 174-175): Orientation Tables for Selecting the Right Flow Sensors
Table 2.1c (p. 183): Up and Downstream Straight Run Requirements
Table 2.1d (p. 184): Velocity Head Requirements Table 2.1e (p. 192): Total Life Cost of Flowmeters Table 2.1f (p. 195): Conversion Among Flow Units (also Tables 10.5b and 10.5c) Table 2.1g (p. 196): Ori ce and Venturi Discharge
Coef cients Tables 2.1h through 2.1l (pp. 197-202): Selection
Recommendations of Some Suppliers ISA Speci cation Form (p. 203)
No industrial measurement is more important that the accurate detection of the ¨ow rates of gases, liquids, and solids. In this chapter, an overview is given regarding the availability and characteristics of some of the most widely used ¨ow sensors. In addition, emphasis is given to the latest developments, such as the polyphase (oil/water/gas), multivariable,
bidirectional, undersea applications, and general guidelines are provided for the selection of the best ¨ow sensor for each application are provided.
