The Greyline DFM 5.1 is designed for "difficult liquids" that would damage regular flow meters - wastewater, slurries, sludge, chemicals, viscous liquids and abrasives. There is no obstruction to flow and no pressure drop. The non-intrusive, clamp-on ultrasonic sensor fits any pipe 1/2" (12.5 mm) Inside Diameter or larger.
Non-Contacting Ultrasonic Sensor
Accurate and Verifiable
Built-in 2-million point Data Logger and Windows Software
USB Outputs to Flash Memory Sticks
Isolated 4-20mA/0-5V Output
2 Programmable Control Relays
Simple 5-key Calibration with Language Selection
The flow meter shall operate with a single-head flow sensor mounted externally on any contiguous pipe material that conducts sound including: carbon steel, stainless steel, ductile iron, copper, FRP, PVC, ABS, or cement lined pipe from 1/2" to 180" (12.5 mm to 4.5 m) ID.
Measure and indicate flow rates from +0.25 to +40 ft/sec and -0.25 to -40 ft/sec (+0.075 to +12.2 m/sec and -0.075 to -12.2 m/sec) with accuracy of ±2% of reading on liquids with entrained particles or gases of 100 microns or larger and minimum concentrations of 75 ppm.
The Doppler technique only works on liquids which contain solids or gas bubbles to reflect its signal. These are "difficult" liquids that may damage regular flow meters: slurries, sludge, wastewater, abrasives, viscous and corrosive chemicals. Because the sensor mounts on the outside of the pipe, there is no pressure drop and no obstruction to flow.
For best performance Doppler sensors should be mounted away from turbulence creating devices like pipe elbows and tees, and away from velocity increasing devices like controlling valves and pumps. Typical accuracy is ±2% of full scale. Doppler instruments include a clamp-on ultrasonic sensor, connecting cable and an electronics enclosure which can be mounted at a convenient location nearby (within 500 ft / 152 m).