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I wish I knew the types of mechanical flow meters!

The market has devices using working principles of all sorts to measure gas or liquid. Of course, electronic flow meters, in many of these cases, look like the best option.

However, some companies disagree! Regardless, you always need to analyze the facts in your specific situation to find your best option. So, what if you decide you need a mechanical device instead of a digital one? Well, take a look at these examples, because one might work for you!


The vane meter lives in the realm of variable area flow meters. A variable area meter has a part inside that moves with the flow, and the meter measures this movement.

The vane meter has a vane opposite a spring. The flow moves the vane against the spring, and its movement will depend on the flow rate. You can connect a transmitter to this type of flow meter to capture your data.


Another kind of variable area flow meter, the float meter has a slightly different working principle. The device has a float inside designed in accordance with the viscosity, density, and flow rate of your product. You also have a tapered tube with the flow scale on it. You have to install this meter vertically with the flow going up.

Image of Float meter
Courtesy of ifsc.edu

When the product flows through this meter, it exerts a force on the float indicating the proportional flow rate on the flow scale.

Positive displacement

Positive displacement (PD) has a broad range of applications and remains a solid solution in many segments. A PD flow meter has two rotating parts and a high-accuracy chamber. The flow fills the space between the rotors, moving them as the fluid heads downstream to the meter.

The volumetric flow is proportional to the rotation of the rotor. Here too, you can connect a transmitter and sensors to collect this information and send it out.


The turbine flow meter is often a cheap solution in process measurement, but you also can find high-accuracy turbines in fiscal applications like custody skids. We already have an article on turbine flow meters here.

Image of turbine flow meter
Courtesy of Enggcyclopedia

Turbine meters translate the movements of an internal rotor with blades into a flow rate. Check out our article to learn about the pros and cons of this type of flow meter.


You can find many other types of mechanical flow meters on the market, but these represent some of the most popular in multiple segments and applications. Will one work for you? You tell us!

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