Flow Meter Performance Monitoring System

Apparatus and associated systems, methods and computer program products relate to monitoring the performance of an operating gas meter by automatic and substantially continuous differential pressure (dP) measurement. Measured dP may be compared against a baseline dP characteristic to determine if the measured dP exceeds a threshold value above a baseline dP characteristic. If the threshold is exceeded, then the system may generate a signal to request repair or replacement of the meter. After installation, some embodiments collect dP data over time and/or over a range of flow rates to automatically learn a baseline dP characteristic under installation conditions. A system may switch from a default baseline dP characteristic to a learned baseline dP characteristic. Some embodiments may further correct volume or flow rate signals for line pressure and/or temperature. Further embodiments provide a passive apparatus to protect a dP sensor against transients in line pressure and/or differential pressure.

TRANSIT-TIME ULTRASONIC FLOW METER

Traditional flow metering devices for pipes like orifice or venturi meters obstruct the flow causing a measurable pressure drop thereby affecting the flowrate & its measurement. Consequently, non-intrusive and non-invasive measurement devices are becoming increasingly popular as they do not generate any pressure losses. The clamp-on transit-time ultrasonic flowmeter is one such device which requires no pipe work and never comes in contact with the liquid, and therefore causes no contamination or pressure drop in the liquid being measured. Transit-time flow meters are based on the time difference between upstream and downstream sound propagation intervals. This approach provides good accuracy (±1-2%), and works well for clean flow or flow with minor particles. The applications of these flowmeters include pure water, sea water, wash water, sewage, process liquids, oils, chemicals, and any homogeneous liquids which are capable of ultrasonic wave propagation.

Fluid Metering

New Calibration Ultrasonic Clamp-on Transducers

State-of-the-art transducer calibration for clamp-on flowmetry is performed using calibration facilities with straight pipes of different diameters. As the pipe size needs to be within the application range of the transducer being calibrated, different pipe sizes are typically required. Especially with big pipes, such flow calibration exercises are expensive.