Positive Displacement (PD) flow meters operate much like repeatedly filling and emptying a beaker to measure flow volume. These meters trap small pockets of fluid within a precision chamber using rotating components, and the rotational speed of these parts is directly proportional to the flow rate. Each rotation represents a fixed volume, allowing the meter to provide highly accurate, direct measurement without external power.
PD meters are ideal for low-flow applications and are highly effective for viscous fluids due to their minimal leakage design. The internal components create a moving seal, ensuring no unmeasured fluid escapes. These flow meters are versatile enough for a wide range of fluids—including corrosive and dirty liquids—and are frequently used for custody transfer of fuels, oils, and chemicals where precision is critical.
Precision flow measurement for diverse applications
Modern PD meters incorporate advanced features like electronic interfacing, high turndown ratios, and temperature compensation to enhance accuracy. They perform exceptionally well in clean, erosion-free environments but can also handle certain levels of impurities depending on design. Common applications include water and gas metering in residences, chemical dosing, fuel measurement, hydraulic testing, and precision industrial processes. With their reliability and accuracy, PD meters remain a top choice for critical volume measurement tasks across industries.