Positive Displacement Flow Meters For Accurate Measurement

Positive displacement flow meters are highly accurate instruments that measure the volume of liquid or gas by repeatedly entrapping fixed amounts of fluid in compartments and counting the number of times these compartments are filled and emptied. Unlike velocity-based meters, PD flow meters provide a direct volumetric measurement, making them ideal for applications requiring precise flow monitoring and custody transfer. They operate mechanically using rotating or reciprocating components such as gears, pistons, lobes, or diaphragms, which move in proportion to the flow. Each movement corresponds to a specific volume, and the total flow is calculated by summing these displacements. Many PD meters also feature mechanical counters or electronic pulse outputs for integration with monitoring systems.