In many industrial metering scenarios, accurate measurement of fluids has always been a basic but crucial task. Whether it is the petrochemical industry, food processing, or pharmaceutical and oil transportation, accurately grasping the liquid flow rate is the key to ensuring quality and efficiency. At this time, the PD meter, that is, the volumetric flowmeter, plays its role.
So, how does the PD meter achieve high-precision measurement? What is its working principle? Next, let's take a look together.
PD is the abbreviation of Positive Displacement, which means "positive displacement". The PD meter measures the volume of the fluid "squeezed out" in the metering cavity to achieve accurate measurement of the flow rate. It does not rely on flow velocity like a turbine flowmeter, nor does it require conductive liquid like an electromagnetic flowmeter. Therefore, the PD meter can work stably under many harsh working conditions.
The core of the PD meter is a set of constantly running mechanical structures, such as gears, elliptical gears, vanes, rotors, etc. Their function is to separate the fluid into "unit volumes" and then drive the rotating device as the liquid flows.
Every time a metering unit passes through the meter, it is equivalent to a fixed volume of liquid passing through. As long as the number of these "metering actions" occurs is counted, the total volume of the fluid can be accurately calculated.
To give a popular example, the PD meter is like a group of small buckets set up on a flowing waterway. Every time the bucket is filled and poured out, a number is counted. The capacity of the bucket is fixed, so as long as the number of times the bucket is filled is counted, the total amount of liquid flowing can be known.
Because it is a "direct volume measurement" and is not greatly affected by factors such as flow rate, pressure fluctuations, and viscosity changes, the accuracy of the PD meter is usually very high, even up to about ±0.1%. This is why it is often used in situations where high precision is required, such as oil loading and unloading, chemical product measurement, and pharmaceutical raw material transportation.
The PD meter has stability and dependability in addition to precision. It is rather straightforward to maintain, has a sturdy construction, and contains few intricate electronic parts. Even in situations with low flow rates or high viscosity liquids, it can continue to function well.
Furthermore, the PD meter can be used with a variety of media, such as water, oil, syrup, alcohol, additives, etc. It can "do it" for the majority of liquids as long as the medium is free of particles or has a low metal corrosive capacity.
The working principle of the PD meter is actually not complicated, but it is this "batch measurement and gradual accumulation" method that makes it stand out among many flow meters. It uses a mechanical structure to "count" the fluid one by one, making the measurement more intuitive and reliable.
For companies that pursue high precision and stability, choosing a PD meter is choosing a reliable measurement method. Its advantages will continue to be reflected in day-to-day production.
