
At ManuFlo, an esteemed Australian company specialising in the manufacturing, sales, and servicing cutting-edge flow meters, we firmly believe that positive displacement flowmeters (PD meters) are an excellent choice for accurately measuring clean liquids across various applications. In this guide, we’ll delve into the workings of PD flowmeters, explore different types of technologies, highlight key benefits, and shed light on their diverse applications.

How do Positive Displacement Flowmeters Work?
Positive displacement flowmeters operate by measuring fluid in discrete volumes. The fluid enters a chamber, gets sealed once it is complete, and produces either an electronic pulse or drives a gear to register the volume as it exits the chamber. This results in precise volumetric measurements, making it akin to filling a bucket to the brim multiple times and then summing up the total volume.
Types of Positive Displacement Flowmeter Technologies
ManuFlo offers a variety of PD flowmeters, each based on the positive displacement principle. Our range includes the oval gear meter, nutating disc meters, spur gear meters, variable area flow meters, screw meters, oscillating piston meters, helical gear meters, and rotary vane meters. These meters use meticulously machined moving blades or gears against uniform chamber walls, ensuring accurate measurements.
Key Benefits of Using Positive Displacement Flowmeters
Positive displacement flowmeters offer several advantages over other metering methods:
1. Accurate Measurement of High and Varying Viscosities: Temperature changes can affect the viscosity of the liquid, leading to inaccuracies in inferential meters. PD meters, however, are unaffected by such changes and provide consistent measurements.
2. Operation at Very Low Flows with Highly Viscous Liquids: PD meters measure low flows of highly viscous fluids, such as oils and greases, without compromising accuracy.
3. No Requirement for Flow Conditioning: Other metering methods often demand straight pipe lengths for representative and reliable measurements, but PD meters don’t require flow conditioning.
4. Versatile Mechanical Design: PD meters can operate with voltage pulse signals and mechanical registers, making them suitable for remote sites with low maintenance requirements.
5. Robust and Low-Maintenance: These meters are engineered to handle noise, vibration, and operate without frequent maintenance, ensuring long-lasting performance.
6. High Accuracy and Turndown Ratio: PD meters provide exceptional accuracy and a wide turndown ratio at a cost-effective price.
Applications of Positive Displacement Flowmeters
ManuFlo’s positive displacement flowmeters find diverse applications, primarily in the following areas:
1. Inventory Management: Ideal for managing chemicals, from detergents to low-concentration caustic and acid solutions.
2. Fuel Consumption Monitoring: Used to monitor fuel consumption in diesel generators at mining and construction sites.
3. Proportional Blending: Small oval gear meters are employed in fuel terminals for blending additives like anti-icing agents, combustion modifiers, and more.
4. Viscous Fluid Applications: Best suited for clean, viscous liquids that can lubricate moving parts, such as fuels, oils, and greases.
5. Low Viscosity Fluids: PD meters can also measure fluids with low viscosity, including water, alcohol, and organic solvents.
6. Food Processing: Suitable for dosing small exact volumes in food processing, such as measuring edible oils, honey, molasses, and chocolate.
At ManuFlo, we are proud to offer exceptional accuracy and repeatability with our range of positive displacement flowmeters. Designed for measuring clean liquids, our PD meters are unaffected by temperature, pressure, or viscosity changes, ensuring reliable flow measurements. With robust and low-maintenance features, our PD meters provide unmatched longevity and cost-effectiveness.
Choose ManuFlo’s positive displacement flowmeters for your flow measurement needs, and experience the pinnacle of precision and reliability. Contact us today for tailored solutions that empower your fluid processes.