Flow meter selection and sizing

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Flow meter selection and sizing

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  • Accurate flow meters can be hard to come by nowadays. Micronics have a great and efficient range that i use when taking measurements in my brewery! http://micronicsflowmeters.com/permanent-flow-meters.asp
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Flow meter selection and sizing

  1. 1. Flowmeter Selection and Sizing -NIDHIN MANOHAR
  2. 2. What is a Flow meter? An ideal flow meter is a group of linked components that will deliver a signal uniquely related to the flow rate or quantity of fluid flowing in a conduit, despite the influence of installation and operating environment.
  3. 3. Flowmeter used for Indication Quantification ( Estimation & Planning) Custody Transfer (Billing) Control ( Demand ) Alarm
  4. 4. Desirable Features of Flowmeter ● Be of intrinsically high accuracy ● Maintain its accuracy under a wide range of liquid conditions ● Have high flow detection sensitivity, even at zero flow ● Have high flow range ability, including reverse flow capacity ● Be of high reliability, requiring little or no maintenance ● Install easily without altering pipe line operating conditions ● Be of low installed cost, as compared to Turbine or PD meters ● Not be subject to wear, or change of calibration through use ● Be of fast response, to detect catastrophic leaks in seconds ● Be capable of monitoring large lengths of pipeline ● Be rugged relative to actual site environmental conditions ● Perform accurately in Multi-product pipelines ● Be capable of detecting and compensating for free gas ● Detect Empty pipe conditions instantly ● ● Not be affected by corrosive or abrasive liquids Produce minimum to zero pressure drop ● Be compatible with many different types of nondescript liquids ● ● Be capable of installation near bends and elbows Require only minimal operating power, for remote area operation
  5. 5. Desirable Features of Flowmeter ● More Information about the process, including pressure and temperature. ● Flowmeters that are easier to calibrate ● Self calibrating flowmeters or flowmeters that can be calibrated with a software package ● Better diagnostics ● A predictive maintenance light
  6. 6. A typical Process Flow Diagram showing Overall Measurement Uncertainties expected in a Fiscal Quality measurement
  7. 7. Prescribed Levels of Metering Accuracy for Petroleum Fluids Canada Offshore Petroleum Board Measurement Guidelines – Oct 2003 Fiscal or Custody transfer Quality measurement Field or Platform allocation Well allocation Measurement Approach Fiscal Quality Near Fiscal Quality Fiscal Allocation Fiscal Well Test Fiscal Multiphase Metering Hydrocarbon Liquid Hydrocarbon Gas 0.25% 1% 1% 5% 3% 5% Typical Uncertainty in Mass Flow rate measurement (%) Liquid Gas 0.25 1 0.25 - 1.0 1.0 - 2.0 0.5 - 5 2-5 10 10 - 20 DTI Measurement Guidelines – December 2003
  8. 8. SELECTION OF FLOWMETERS • Selection of a flow meter as per the requirement sometimes poses a challenge to instrumentation engineers and consultants because of i) varying requirements of the installation ii) availability of large no. of instruments in the market iii) absence of comparative data Here a general approach is considered
  9. 9. • FLOWMETER CLASSIFICATION : - Different classification of flowmeters Additive / Extractive Invasive / Non Invasive Insertion / Clamp-on Mass flow / Volume flow / Point velocity -Based on the technology employed in metering, about 50 different types of flow metering devices can be identified. -These are usually Classified into 9 or 10 groups
  10. 10. Group Description 1 Orifices, Venturi's and Nozzles 2 Other differential pressure types 3 Positive displacement types 4 Rotary turbine types 5 Fluid oscillatory types 6 Electromagnetic types 7 Ultrasonic types 8 Direct and indirect mass types 9 Thermal types 10 Miscellaneous types
  11. 11. FLOWMETER SELECTION Preliminary selection is based on the application to which the meter is to be put. Table below shows the check list for the suitability of various flowmeters against different applications
  12. 12. Table 2.1 Broad areas of application Group 1 2 3 4 5 6 7 8 9 10 Type Orifice Venturi Nozzle VA Target Averaging Pitot Sonic nozzle Sliding vane Oval gear Rotary piston Gas diaphragm Rotary gas Turbine Pelton Mechanical meter Insertion turbine Vortex Swirlmeter Insertion vortex Electromagnetic Insertion electromagnetic Doppler Transit time Coriolis (direct) Twin rotor (indirect) Anemometer Thermal mass Tracer Laser Application Liquids (see note 1) A B C D ? E + + F G H Gases (see note 2) J K L ? ? ? M N ? ? ? ? ? ? + + Miscellaneous (see note 3) P Q R S ? ? ? ? ? ? ? ? ? ? ? ? ? ? + ? ? ? ? ? ? + ? ? ? ? ? ? ? ? ? + ? + + + ? ? ? ? ? ? ? ? + + + ? + ? + ? + ? ? ? ? ? ? + + ? ? ? ? + + ? ? ? ? ? ? ? + + ? ? + + ? T ? ? ? + Key is suitable; generally applicable ? is worth considering; sometimes applicable + is worth considering;limited availability or tends to be expensive A blank indicates unsuitable; not applicable NOTE 1. Liquid applications are indicated by the following NOTE 2. Gas applications are indicated by the following : A General liquid applications (<50cP (<0.05OPa.s) J General gas applications B Low liquid flows (<0.12m3/H)(<2 L /min) K Low gas flows (<150 m3/h) C Large liquid flows (>1000m3/h)(>1.7x10 L/min) L Large gas flows (>5000 m3/h) D Large water pipes (>0.5m bore) M Hot gases (temperatures <200 deg.C) E Hot liquids (temperatures >200 deg.C) N Steam F Viscous liquids (>50 cP) (>0.05 Pa.s) Note 3. Miscellaneous applications are indicated by the following G Cryogenic liquids P Slurries and particle flows H Hygienic liquids Q Liquid liquid mixtures R Liquid gas mixtures S Corrosive liquids
  13. 13. SELECTION PARAMETERS • • • • • Performance considerations Fluid property considerations Installation considerations Environment considerations Economic factors
  14. 14. 1 Table 2.2 Selection procedure variables Performance Accuracy Repeatability Linearity considerations Rangeability Pressure drop Output signal characteristics Response time Uncertainty Orientation Flow direction Upstream and downstream pipework Line size Location for servicing Effect of local vibration Provision of accessories like filters, straighteners, transducers etc. Hazardous atmosphere Effect of pulsations/unsteady flow 2 Fluid property considerations Liquid or gas Temperature Pressure Density Specific gravity Viscosity Lubricity Presence of other components Chemical properties Surface tension Compressibility Real gas effects Abrasiveness Presence of other phases 3 Installation considerations Orientation Flow direction Upstream and downstream pipework Line size Line size Location for servicing Effect of local vibration Provision of accessories like filters, straighteners, transducers etc. Hazardous atmosphere Effect of pulsations/unsteady flow 4 Environments considerations Ambient temperature effects Humidity effects Safety factors Pressure effects Electrical interference 5 Economic Purchase price Installation costs Operation costs Pumping power and headloss Technical optmization Meter life Spares cost and availability Maintenance costs Calibration costs
  15. 15. Performance considerations Accuracy : is the closeness to truth. considering application of flowmeter, eg. Custody transfer very high accuracy is required. Should be careful about method of specifying errors by the vendors ie., whether % of Full scale Or % of reading Repeatability : is the ability of a meter to reproduce a measurement each time a set of conditions are reproduced and is expressed as the allowable percentage deviation from the stated value under a given set of conditions. Is a measure of the stability of the meter
  16. 16. Good Repeatability Good Accuracy Bad Accuracy
  17. 17. Rangeability : is the ratio of the maximum to minimum flowrates for a given performance. A judicious choice is needed for the application since rangeability differs with the meter selected. eg. Orifice plate - 3:1 to 4:1 Thermal mass flow meter/PD 100:1 to 500:1 Pressure drop at maximum flow: The pressure drop caused by the meter is important since it may affect process efficiency. In liquid applications extreme pressure drops can lead to cavitation and consequent faulty metering
  18. 18. Output signal characteristics : Normally a flow meter may directly or indirectly measure Volume rate of flow Mass flow rate Totalized flow Mean flow capacity Point velocity These output may be in voltage, current or pulses which may have to be interfaced with flow computers, data loggers, alarm systems etc. The particular instrument selected should be compatible to these.
  19. 19. Group – 1 Group – 2 Group – 3 Group – 4 Group – 5 Group – 6 Group – 7 Group – 8 Group – 9 Group – 10 0.03 0.1 0.3 1.0 3.0 Uncertainty % Flow rate Typical Performance Distribution of Flow meter Groups 10 30
  20. 20. Performance Factors in meter selection Group 1 2 3 4 5 6 7 8 9 10 Type Linearity (%) Repeatibility (%) Orifice # # Venturi # # Nozzle # # Variable area +/-1%FS to +/-5% FS +/-1%FS to +/-5% FS Target NS NS Averaging Pitot # # Sonic nozzle +/-0.25% +/-0.25% R Sliding vane +/-0.1R to +/-0.3%R +/-0.01%R to +/-0.05% R Oval gear +/-0.25%R +/-0.05%R to +/-0.1% R Rotary piston +/-0.5R to +/-0.2%R +/-0.2% R Gas diaphragm No data No data Rotary gas +/-1% +/-0.2% Turbine +/-0.15 R to +/-1% R +/-0.02%R to +/-0.5% R Pelton +/-.25R to +/-0.2% R +/-0.1%R to +/-0.25% R Mechanical meter No data +/-1% FS Insertion turbine +/-.25 R to +/- 5% R +/-0.1% R Vortex +/- 1 % R +/-0.1%R to +/-1% R Swirlmeter <+/-2% R NS Insertion vortex +/-2% +/-0.1% R Electromagnetic +/-0.5%R to +/-1% R +/-0.1% R to +/-0.2%FS Insertion +/-2.5%R to +/-4% R +/- 0.1%R Electromagnetic Doppler No data +/-0.2% FS Transit time +/-0.1R to +/-1% R +/- 0.2%R to +/-1%FS Coriolis Twin NS +/-0.1%R to +/-0.25% R rotor No data No data Anemometer Thermal mass Tracer Laser Pressure Rangeability X drop at Flow Response time : 1 where X maximum parameter flow 3 or 4 3-4 R # 3 or 4 2 R # 3 or 4 2-3 R # 10 3 R No data 3 3 R NS # 1-2 Vm # 100 : 1 3-4 R NS 10 to 20 4-5 T > 0.5 ms 4 T < 0.5 ms 10 to 250 4-5 T > 0.5 ms 100 2 T > 0.5 ms 25 2 T < 0.5 ms 5 or 10 3 R 5ms to 25 ms 4 or 10 4 R 5ms to 25 ms 10 or 280 3 R 50 ms 10 to 40 1-2 Vp 5ms to 25 ms 4 or 40 3 R 0.5s minimum 10 or 30 3 R NS 15 or 30 1 Vp 5ms 10 to 100 10 1 1 R Vp > 0.2 s NS 5 to 25 10 to 300 10 to 100 10 to 20 1 1 2-5 3-4 Vm R R R 0.1s to 3600s 50ms 0.1s to 120s No data +/-0.5R to +/-2% R +/-0.2% FS +/-0.2%FS to +/-1% R 10 to 40 10 to 500 2 2 Vp R No data 0.12 to 7 s No data No data No data +/-0.5% R Upto 1000:1 Upto 2500:1 1 1 Vm Vp No data No data
  21. 21. Fluid Property Considerations Fluid Property Considerations Fluid Temperature & Pressure/Vacuum Provision for Compensation Materials should stand the temp/pressure/vacuum Fluid Density and Specific Gravity Provide for compensation (on line) ? Viscosity Gases  effect is small Rangeability and performance affected Chemical Properties Compatibility of materials Compressibility Single Phase/Multi-phase Fluid
  22. 22. Group Type 1 Orifice Maximum Temperature Minimum Gas (G) or Two or pressure range Liquid (L) more ReD 4 400 <+650 3 x 10 L,G P Venturi 400 <+650 5 L,G P 4 1 x 10 400 700 <+650 -80 to 400 2 x 10 No data L,G L,G N N Target 2 Nozzle VA 100 -40 to 120 3 x 10 4 L,G S 1 x 10 4 L,G N Averaging Pitot 400 Sonic nozzle 3 400 Sliding vane 100 Oval gear 100 Rotary piston 170 Gas diaphragm 200 <+540 <+650 -30 to +200 -15 to + 290 -40 to +170 -30 to +200 2.5 x 10 4 G N 1 x 10 3 L N 1 x 10 2 L N 1 x 10 2 L N G N G L,G N 4 L,G L,G L,G N N N 2.5 x 10 3 Rotary gas Turbine 100 3500 -40 to +150 -268 to +530 Pelton Mechanical meter Insertion turbine 600 70 250 -225 to 530 -25 to +200 -50 to +430 1 x 10 Vortex Swirlmeter 260 100 -200 to + 430 -40 to +110 2 x 10 No data 4 L,G L,G P N 70 300 20 -30 to +150 -60 to +220 +5 to +25 3 6 Insertion vortex Electromagnetic Insertion electromagnetic 5 x 10 No limit No data L,G L L N S/P N 7 Doppler * -20 to +80 5 x 10 3 L S 5 x 10 3 L,G N/P 1 x 10 2 L P 4 L L,G L,G L,G L,G N N N P N 4 5 Transit time 8 9 10 200 Coriolis Twin rotor Anemometer Thermal mass Tracer Laser 390 400 20 300 No data No data Key S is suitable P is possible N is not suitable * is dependent on the rating of the pipe wall -200 to +250 -240 to 400 -240 to 350 -200 to 400 0 to 100 No data No data 1 x 10 2 1 x 10 No data No data No limit No limit
  23. 23. The Effect of Pressure Deviations on a Variable-Area Flowmeter {PRIVATE}Maximum flowrate, L/min Fluid type: Air 2.23 1.65 1.30 2.26 2.28 2.32 Fluid type: water 4.82 4.82 4.82 4.86 4.89 4.95 Fluid temperature, °F Outlet pressure, psi 70 70 70 90 110 150 0 15 35 0 0 0 70 70 70 90 110 150 0 15 35 0 0 0 As Table shows, the effect of pressure deviations can be quite significant. This table was created using data from a variable-area flowmeter that was calibrated for air at 70°F and with the outlet of the flowmeter vented to the open atmosphere (i.e. , 0 psi of outlet pressure).
  24. 24. Installation Considerations Pipe work Orientation Flow Direction Will the meter work only in one direction ? Chances or reverse flow  check valve ? Bi-directional meters to be calibrated in two directions Upstream/Downstream Pipe Works Orientation Straight Length Line Sizes Availability of meters of various bore sizes Local Vibration Provide pipe supports ? Provide pulsation (fluid) dampers ? Location of Valves Provide valves downstream of meter Provide upstream (full bore) and downstream valves for isolation of meter – provide bypass line. Electrical connections – EMI/RFI Elimination Hazardous atmosphere Pulsations in Flow Fast response instrumentation needed ?
  25. 25. Group 1 2 3 4 5 6 7 8 9 10 Type Orientation Orifice Venturi Nozzle VA Target Averaging Pitot Sonic nozzle Sliding vane Oval gear Rotary piston Gas diaphragm Rotary gas Turbine Pelton Mechanical meter Insertion turbine Vortex Swirlmeter Insertion vortex Electromagnetic Insertion electromagnetic Doppler Transit time Coriolis Twin rotor Anemometer Thermal mass Tracer Laser Key H is horizontal flow VU is upward vertical flow VD is downward vertical flow I is inclined flow + is mixng length Direction H,VU,VD,I H,VU,VD,I H,VU,VD,I VU H,VU,VD,I H,VU,VD,I H,VU,VD,I H,VU,VD,I H H,VU,VD,I H H,VU,VD,I H,VU,VD,I H,VU,VD,I H,VU,VD,I H,VU,VD,I H,VU,VD,I H,VU,VD,I H,VU,VD,I H,VU,VD,I H,VU,VD,I H,VU,VD,I H,VU,VD,I H,VU,VD,I H,VU,VD,I H,VU,VD,I H,VU,VD,I H,VU,VD,I H,VU,VD,I U,B U U U U U,B U U U U U U,B U,B U U U,B U U U U,B U,B U,B U,B U U U,B U U,B U,B U is uni-directional flow B is bi-directional flow R is rcommended N is not necessary P is possible Quoted range of Quoted range of u/s lengths d/s lengths 5D/80D 0.5D/29.5D 5D/80D 0D 6D/20D 2D/25D >5D 0D 0D 0D 0D 0D/10D 5D/20D 5D 3D/10D 10D/80D 1D/40D 3D 20D 0D/10D 25D 10D 0D/50D 0D 20D 10D/40D No data + 0D 2D/8D 4D 2D/8D 0D 3.5D/4.5D 2D/4D >0D 0D 0D 0D 0D 0D/5D 3D/10D 5D 1D/5D 5D/10D 5D 1D 5D 0D/5D 5D 5D 2D/5D 0D 5D No data + 0D Filter N N P N P N L L L G G P R R L,G N N N N N L L,G L L L,G L,G N P Pipe bore range mm 6 to 2600 >6 2 to 600 12 to 100 >25 >=5 N N N N N 5 to 600 4 to 20 12 to 1800 >75 12 to 200 12 to 400 >200 2 to 3000 >100 S N/P P N N N Unlimited
  26. 26. Group – 1 Bypass Group – 2 Liquid Group – 3 Types Gas Insertion Types Group – 4 Insertion Types Group – 5 Group – 6 Group – 7 Group – 8 Group – 9 Group – 10 1 10 100 1000 10000 Line size, mm Note:- The shaded areas represent the overlapping range of insertion and full bore meters. Size distribution of flowmeter group
  27. 27. • Environments considerations Ambient temperature effects Humidity effects Enhances corrosion Powers Electrical Insulation Efficiency Safety factors Pressure effects Electrical interference
  28. 28. Group 1 2 3 4 5 6 7 8 9 10 Type Temperatu Intinsically safe Water and 1) version explosion proof re effect Orifice Venturi Nozzle VA Target Averaging Pitot Sonic nozzle Sliding vane Oval gear Rotary piston Gas diaphragm Rotary gas Turbine Pelton Mechanical meter Insertion turbine Vortex Swirlmeter Insertion vortex Electromagnetic Insertion electromagnetic Doppler Transit time Coriolis Twin rotor Anemometer Thermal mass Tracer Laser 4 3 3 3 3 3 3 4 4 4 4 4 3 3 3 3 2 2 1 1 1 3/4 3/4 1 2 3 4 1 1 + + + A NA + A A A A A A A A A A A A A A A A NA A No data NA A N NA Key N is not necessary A is available NA is not available + is dependent on differential pressure measurement 1) 1is low 5 is high + + + A A + NA A A A NA NA A A A A A A N A N A A A/NA No data NA A N NA EMI or RFI 1) effect 1/2 1/2 1/2 1 3 2 1/2 1/3 1/3 1/3 1/3 1/3 4 3 3 3 4 3 3 3 3 4 4 4 4 2 2 1 4
  29. 29. Economic Considerations Purchase price Installation costs Operation costs Head loss (Pumping cost) Meter life Spares cost and availability Maintenance costs Calibration costs
  30. 30. Calibration • All flowmeters require an initial calibration. • Need to recalibrate depends to a great extent on how well the meter fits the application.
  31. 31. Table 2.7 Selection by economic factors Installation Calibration Operations Maintenance Group Type costs costs costs costs 1 2 3 4 5 6 7 8 9 10 Orifice Venturi Nozzle VA Target Averaging Pitot Sonic nozzle Sliding vane Oval gear Rotary piston Gas diaphragm Rotary gas Turbine Pelton Mechanical meter Insertion turbine Vortex Swirlmeter Insertion vortex Electromagnetic Insertion electromagnetic Doppler Transit time Coriolis Twin rotor Anemometer Thermal mass Tracer Laser 2/4 4 3 1/3 3 2 2 3 3 3 3 3 3 4 3 2 3 3 2 3 2 1/3 1/4 3 3 3 3 2 5 1 1/4 3 2 3 3 1 5 4 3 3 4 4 3 2 3 3 4 3 3 3 1 3 4 3 2 4 - Key 1 is low 5 is high Note For purchase price see fig. (a) and (b) of fig 2.6 3 2 2 2 2 2 3/4 4 4 3 1 3 3 2 2 A 3 3 2 1 2 1 1 4 3 1 2 4 4 2 3 3 1 3 2 2 4 4 3 2 3 4 4 3 2 3 3 3 3 3 3 3 3 3 3 4 2 5 Spares costs 1 3 2 1 3 2 5 5 5 4 2 3 4 3 3 3 3 3 3 3 2 2 2 3 3 3 3 4 5
  32. 32. Example-1 Select a flowmeter for the following requirement: a. b. c. d. e. f. g. h. i. Application Line size Fluid Operating pressure : Operating Temperature Uncertainty Output Pipe work Pressure drop at max flow : : : : : : : : : Custody Transfer Application 12 inches Natural Gas 20 bar 300 +/- 50C 0.25% of actual flow To interface with flow computer No limitation Medium 1. 2. 3. 4. 5. Groups to be considered For uncertainty 0.25% Flow rate Line size Pressure drop at max flow : : : : : 1, 2, 4, 5, 10 Select L in Table – 2 1, 2, 3, 4, 7 Table – 5 6000 m3/hr in 12 inch line 1, 2, 3, 4, 5, 6, 7, 10 Table - 7 1, 2, 3, 4, 5, 6, 7, 8, 9,10 Table - 4 : Group 4 Group 2 Group 1 Answer : I Choice II Choice III Choice : :
  33. 33. Example-2 Select a flowmeter for the following requirement: a. b. c. d. e. f. g. h. i. Application Line size Fluid Operating pressure Operating Temperature Uncertainty Output Pipe work Capital Investment 1. 2. 3. 4. 5. 6. 7. 8. For (a) and (c), select S in Table – 2 Groups to be considered : For uncertainty 1% : Flow rate : Find velocity and re : Line size : Installation ( straight length) : Economic Factors : 1, 2, 3, 4, 5, 6, 7, 8, 10 1, 3, 4, 5, 6, 7, 8 Table – 5 3.5m3/s in 25 mm line 1, 3, 4, 6, 7, 8 Table- 8 2, 3, 4, 5, 6, 7, 8, 9 3, 6, 8 3, 6, 7, 8 Table 10 Answer : : : : : : : : : : : I Choice II Choice III Choice Acid Production 25 mm Hydrochloric Acid 3 bar 250 - 50C 1% of actual flow To interface with flow computer 3D upstream, 3D downstream, Horizontal Item is not critical : : Group 6 Group 3 Group 8 Table-2 Table-5 Table-8 Table-10
  34. 34. Example-3 Select a flowmeter for the following requirement: a. b. c. d. e. f. g. h. i. Application Line size Fluid Operating pressure : Operating Temperature Uncertainty Output Pipe work Capital Investment : : : : : : : : : Metro water supply 1800 mm water 17 bar 250 - 50C 1% of actual flow To interface with flow computer No limitation Item is not critical 1. 2. 3. 4. 5. 6. 7. Groups to be considered For uncertainty 1% Flow rate Find velocity and re Line size Pressure drop at max flow Economic Factors : : : : : : : 1, 2, 4, 5, 6, 7, 9, 10 select D in Table – 2 1, 2, 3, 4, 5, 6, 7, 8 ,9 Table – 5 3700 l/s in 1800 mm line 1, 2, 3, 4, 5, 6, 7, 8, 9,10 Table- 8 1, 2, 4, 6, 7, 10 1, 2, 3, 4, 5, 6, 7, 8, 9,10 1, 2, 3, 6, 7, 9 Table 10 : Group 6 Group 1 Group 2 Answer : I Choice II Choice III Choice : :
  35. 35. Example–4 Groups to be considered Application : Line size : Fluid : Operation Pressure Operating Temperature Uncertainty required Steam Billing : N in Table 2 0.3 : 1, 2, 4, 5, 10 Table 8 Superheated steam : 1, 2, 4, 5, 10 Table 2 : 1000 psi : 1, 1, 5, 8 Table 6 : 300oC : 1, 2, 5, 8, 9 Table 6 : 0.5% of actual flow : 0, 4, 6, 8 Table 5 Flow rate : 4 kg/s to 45 kg/s Output : Pulse for totalization Pipe work : Not specified Budget : Very limited Answer : No meter satisfies the specifications : 1, 2, 6
  36. 36. Table -7 Table -4
  37. 37. Manufacturers are anxious to help customers pick the right flowmeter for a particular job. Many provide questionnaires, checklists and specification sheets designed to obtain critical information necessary to match the correct flowmeter to the job.
  38. 38. • Technological Improvements of flowmeters must be considered. • Availability of computer programs to perform tedious calculations often necessary for selecting flowmeters
  39. 39. Software for Flowmeter selection Brooks Instruments For selection and sizing of metal tube/glass tube Variable area flowmeter Fisher – Rosemount For selection of vortex meters Dos based C. Johnson – Yokogawa Windows based flow sizing program Admag magnetic flowmeters and Yewflow vortex flowmeters The Foxboro Co, Mass Software “Flow Expert” Interactive, Windows – based Menu Flowmeter review (Catalogue) Selection guide Sizing for orifice plates/integral orifice assembly Sizing for vortex meters, Coriolis meters, magmeters Physical properties of fluids Engineering Measurements Co., Program ‘Emcosize’ Interactive Selects different types of meters for same application
  40. 40. Honeywell Specific application driven softwares for Coriolis, Magmeter and DP devices Has build – in checks and warnings Krohne, America Program ‘Corisize’, DOS – based Selects the correctly sizes Coriolis meter Anticiplated pressure loss, liquid velocity and accuracy based on nominal flow are predicted Endress + Hauser Instruments Sizes 24 different types of flowmeters working or Coriolis/Vortex/Magmeter Technologies Provides data for 270 fluids Abb Instruments Software ‘Genie’ Selects the meter, prints out the part number and the catalogue price. George Fischer Inc., Selection of Signet paddle-wheel insertion meter Selection based on flow profile dependent on Reynolds N., Pipe I.D., Flow rate, Viscosity, Density Indicates Whether a sensor will/may/will not work.
  41. 41. Flowmeter selection software Windows based Flowmeter selection program as per BS 7405 Dos based Flowmeter Selection and Sizing software FMSEL 2.0
  42. 42. Windows based Flowmeter selection program as per BS 7405
  43. 43. Dos based Flowmeter Selection and Sizing software FMSEL 2.0
  44. 44. Flowmeter Sizing
  45. 45. Orifice with flange tappings
  46. 46. Orifice with corner tappings
  47. 47. Orifice with D and D/2 tappings
  48. 48. Classical Venturi tube
  49. 49. Long radius nozzle
  50. 50. ISA 1932 nozzle
  51. 51. Venturi nozzle (ISA inlet)
  52. 52. Meter Sizing in Turbine Meters Turbine meters are sized by volumetric flow rate. When sizing the meter, it is recommended that the application maximum flow rate is approximately 70 to 80 percent of the maximum flow rate. This results in a good flow range – 7 or 8:1. For optimum performance and flow range, most turbine meters are designed to a nominal maximum velocity of 30ft/s (9.14m/s). Consequently, if the turbine meter is selected to be of the same size as the pipeline, the meter flow range will be severely limited and will only be approximately 2 or 3:1. If the turbine flow meter is sized on volumetric flow rate, it will be smaller than the pipeline.
  53. 53. Meter sizing in Vortex meters The meter minimum flow rate is established by a Reynolds number of 10000, fluid density and a minimum acceptable shedding frequency for the electronics. The maximum flow rate is governed by the meter pressure loss(typically two velocity heads), the onset of cavitation with liquids and compressibility with gases. On low viscosity products like water, gasoline and liquid ammonia, and with an application maximum velocity of 15 ft/s (0.45m/s), vortex meters can have a rangeability of 40:1 with a pressure loss of approximately 4 psig. On liquid applications, it is necessary to verify that sufficient line pressure exists to prevent cavitation in the vortex meter.
  54. 54. Case Study – VenCorp Australia Pipeline company crews in the Australian state of Victoria have installed 102 new ultrasonic, turbine and coriolis meters to measure at intermediate custody transfer points during a major gas industry reorganization and privatization. Industry reformers have created one transmission company, three distribution companies and three retail companies from what was a single, vertically integrated organization in Victoria. As a result of the restructuring, new custody transfer meters were required at the interfaces between the transmission and distribution systems
  55. 55. Of the 102 new meters installed in the 18-month, $20million project, 18 multipath ultrasonic meters are used at large flow installations, 60 turbine meters for intermediate flows and 24 coriolis meters for small volumes. Technologies were sought that would not only achieve the required measurement uncertainties, but would minimize the meter installations’ life cycle costs. Reduction or elimination of the need for regular recalibration at pressure is highly desirable as the cost of removing the meter and shipping from Australia is high. Multipath ultrasonic meters were generally chosen for category A and B meters, turbine meters for category C and coriolis meters for category D.
  56. 56. For large sites or sites where bi-directional flow is a possibility, multipath ultrasonic meters were chosen as they incorporate continuous internal diagnostic checks which indicate if any of the ultrasonic paths is fouled, if the meter is subject to external noise or if any of the ultrasonic transducers is deteriorating. Monitoring the measured velocity of sound will show if there is any change in a critical dimension or if the reference clock has drifted. If there is any doubt about the meter’s operation, a dry calibration can be performed which will verify correct operation. In principle, there should be no need to return the meter for high-pressure calibration if there are no faults showing in the meter diagnostics and the measured velocity of sound is consistent with the gas passing through the meter. Ultrasonic meters were installed at sites with peak hourly flows exceeding 40,000 m3/hr. The meter sizes range from 200 mm to 400 mm (8 to 16 in.).
  57. 57. In sizes less than 200 mm, cost considerations led to the selection of turbine meters. Turbine meters that comply with ISO 9951: Measurement of Gas Flow in Closed Conduits – Turbine Meters were chosen. They were tested to ensure compliance with minimum perturbation requirements with 2D upstream of the meter because this design maximized site-selection flexibility and minimized the metering-skid physical dimensions. Turbine meter sizes below 50 mm were rejected because the turndown ratio suffers at the small sizes due primarily to dominant bearing effects.
  58. 58. For small-meter installations, coriolis meters were chosen because they offer high turndown ratio capability and can be calibrated with water and used to measure gas with an added uncertainty of less than 0.5%. Coriolis meters exhibit a turndown ratio in excess of 100:1 and cannot be damaged by excessive flows. Many small offtakes, especially country towns serving small populations of residential users without significant industry, have large turndown ratios with only a small maximum flowrate.
  59. 59. 2006 Flowmeter User Study Results Flow Research (www.flowresearch.com) recently conducted a six-month survey of the flowmeter user community. The survey, which was undertaken in cooperation with Venture Development Corporation ( www.vdccorp.com) and Flow Control magazine, was conducted in the second half of 2005 via an Internet-based questionnaire
  60. 60. ThankYou !

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