How to measure oil flow?

Today, we discuss the kind of viscosity Sunflower Oil uses for lubrication and how do we measure its flow in the production line? Well, that’s interesting! In the article here, we dig deep into the query and give you some powerful insights into this.

To begin with, whether you are using Sunflower oil all the time or only see sunflowers in pictures of farms, it exists as its own industry. Choosing the right meter definitely requires knowing the properties of the application.

What do you need?

Besides the process parameters, you’ll also need to consider accuracy, chemical compatibility, space constraints, and installation requirements.

So what do lubrication oil processes need? The primary requirement for measuring the flowrate of lubrication oil is the smaller flowrates, a meter should be able to measure low flow rates like 0.2 to 0.5lit/min.

However, being a viscous fluid, the oil can lead to measurement difficulties due to turbulence and bubbles. So, the flowmeter should deal effectively with the turbulence and bubbles.

You should get a meter with as few moving parts as possible because mechanical moving parts may cause temperature changes and we have to maintain the temperature of the oil between 20-50˚C.

Taking all this into account gives us a couple of good choices: a Coriolis meter, an ultrasonic meter, Magnetic flow meter and Variable Area flowmeter.
Let’s see how they work for this application.


Coriolis meter

Coriolis meter is a real mass flow meter. As this flowmeter measures the mass flow, the errors due to physical properties are very less. That means you won’t have to worry about temperature and pressure changes. To learn more about Coriolis meters, you can check out our article on them.

Coriolis meters work well for the oils because they provide great accuracy, and can measure other parameters besides flow, like density. This feature allows better quality in the product. Endress+Hauser, Krohne, Yokogawa, and Siemens all offer density measurement in their Coriolis meters.

You can also measure viscosity, but not every supplier provides this feature. For example, Endress+Hauser has its patented Torsion Mode Balanced (TMB) system for measuring viscosity.

As Coriolis meters have no moving parts, you’ll also see lower costs in maintenance than the other meters. You can check out the following examples:

Promass E 100: Endress+Hauser

Krohne OPTIMASS 7400

Siemens SITRANS F C MASS 2100 DI 1.5

Ultrasonic meter

This non-intrusive flow meter uses sound waves to measure. It offers moderate accuracy. For more on ultrasonics, you can read our article on them.

Ultrasonics may work well for lubrication oil processes because they have no moving parts, wide ranges, and generally minimal pressure drops and maintenance.

Clamp-on meters don’t make contact with the product, reducing the risk of contamination or leakage. However, compact ultrasonics provides easy installation. For more applications of ultrasonic flow meters, check this article out.

If you decide to go ultrasonic, keep in mind its limit on pipe diameter and the smaller flow rate. For some vendors, the range starts at 10 mm and goes to 3000 mm. But this oil flows at around half a liter per minute, so you should take your pipe size and the flowrates into account.

Examples of ultrasonics:

Sick FFU

Krohne Altosonic III

Magnetic flowmeter

Magnetic flowmeter can also be considered for flow measurement of the oil. But it only measures flow of conducting fluids, since oil is non-conducting fluid, the oil flow measurement is not possible with Magnetic flowmeter.

If your application is water or highly conducting liquid, then Magnetic flowmeter is the best choice.

Picomag Smart Electromagnetic Flow meter with wireless remote access
in the shop from 480 €

Variable area flowmeter

A variable area flowmeter can also be considered as an option for flow measurement of lubricating oil. But it provides visual flow measurement i.e. no analog 4-20 mA output. Therefore, this option does not benefit you in oil flow measurement.


Owing to a Lubrication oil’s smaller flowrates and viscous nature, it creates some unusual challenges. On the other hand, Magnetic Flowmeter, Variable area flowmeter and ultrasonic flowmeter has its own limitations for oil flow measurement. Therefore, we suggest that Coriolis meter is a suitable option which can give you a reliable flow measurement!

We have more information on other flow applications if you’d like to read up on them. If you have any questions around, Ask Alex!

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