Competition Other types of flow meters Thermal Mass flow competition
Flow Meters All of these technologies except Thermal and Coriolis measure flow based on density of the gas at the pressure and temperature when the measurement is made
Why measure Mass Flow Not effected by process changes Repeatability in flow measurements Process Operations based on mass balance (mass is conserved) Combustion is based on mass
Orifice Plate PP
Orifice Plates Proven method of flow measurement Well accepted Often customer’s first choice
Venturi Advantage of a Venturi is much of the pressure loss is recoverable Disadvantage installed cost ΔPΔP
Averaging Pitot Tube AKA – Annubar Benefits of sampling velocity at different points. No permanent pressure loss.
Averaging Pitot Tube
DP vs. Flow Differential Pressure Flow Measurement - Measures flow at operating gas density (actual conditions) - Square root relationship between flow and pressure drop -Poor low flow sensitivity -Limited Turndown - May consumes pressure
Vortex Flow Meters Number of vortices dependent upon Reynolds Number
Vortex Meters In line instrument (few insertion style) –Price increases dramatically with pipe size Require minimum velocity to generate vortices –Reynolds Number dependent –Poor low flow sensitivity Measure higher flow rates than Thermal Not Mass Flow
Turbine Flow Meter Pulse output that goes to electronics to calculate flow rate, total flow, or both
Turbine Flow Meter Issues: –Moving parts in the flow path Clean gases only –Measure flow at actual operating conditions Not mass flow (Need to adjust for gas density) –Pressure Drop
Ultrasonic Transit Time Requires Pressure and Temperature correction High rangeability Clamp on design Expensive
Ultrasonic Flare Flow Meter
Positive Displacement Mechanical device – moving parts Requires clean/dry gas Pulse output Totalized flow rather than flow rate Requires pressure and temperature correction
Coriolis Mass Flow Direct Mass Flow –High Accuracy –Very high cost –Limitations on pipe sizes (12 inch maximum) –May not be suitable for low pressure gas flow applications
Advantages of Thermal Mass Flow Low flow capabilities Low maintenance High Turndown Good accuracy Excellent repeatability Easy to install Lowest cost of ownership
THERMAL COMPETITION
Competition FCI Sierra Instruments Fox Thermal E+H Kurz Instruments Magnetrol Eldridge
Sierra Boiler Trak Sierra “Boiler Trak” Low cost flow meter for natural gas measurement. - No Hazardous Area Approvals - Standard Air Correlation calibration - Actual gas calibration extra - Fragile light duty epoxy, glass coated ceramic sensor
FCI ST50/ST51 –Low cost low feature ST98 –Workhorse for heavy process industry
FCI ST100 Many features –Graphic display –Optical touch keypad –Multiple sensor tips –4 conduit openings –2 mA + 1 pulse output –Multiple digital outputs –Optional alarms –4-20 mA input –5 gas calibration –Data logger –Markings on probe Expensive Lot of nice features that few customers need
FCI Veri Cal ST100 only
Fox FT3 Only checks electronics
Other Calibration verification of other thermal flow meters: –Sierra 640S – connect to computer, only checks electronics –Eldridge – none –Magnetrol – two point – no flow and simulated high flow
Calibration Verification Sage –Insitu calibration –No hardware required –Tests both sensor and electronics –Information on nameplate No need to find documentation –Accepted by customers
Hazardous Area Class 1 Div 1 Hazardous conditions occur during normal operation Requires rigid conduit and conduit seals
Hazardous Area Class 1 Division 2 Hazardous conditions only occur during upset Flexible conduit No seals
Hazardous Areas Only have Class 1 Div 1 Approval –Fox FT3 –FCI ST100 –Sierra 640S –Eldridge Master-Touch
Advantage of Sage In Situ calibration verification Lowest power consumption Graphic display Compact enclosure Competitive pricing Real gas calibration Excellent customer service Competitive pricing Good delivery