Flowmeters determine the mass or volume flow rate of a gas or liquid – i.e. the quantity of a medium that flows through a cross-section in a specific period of time. Modern flowmeters have to meet complex requirements: they must be accurate, easy to integrate into various programmable logic controllers and monitoring systems, and comply with all industry-specific standards.
Bürkert offers a wide range of mechanical and electronic flowmeters based on different operating principles, such as electromagnetic flowmeters (EMF) or surface acoustic wave (SAW) flowmeters. From simple mechanical methods to advanced multiparameter measurements – we deliver bespoke solutions tailored to your application, from the tiniest single droplet to the highest flow rates.
A flowmeter provides measured values that make it possible to determine the quantity of a fluid flowing through it. These fluids can be gases or liquids, and have different properties. For media with a constant density, such as water, it is recommended to specify the volume flow rate. The flowmeter then measures the quantity per unit of time – in litres for liquids and in cubic metres for gases.
If the density changes due to external influences such as pressure or temperature differences, it makes more sense to measure the mass flow. The mass flow describes how much mass of the medium flows through the system in a certain time and is measured, for example, in kilograms per second.
Flowmeters measure the physical properties of a medium, then use this information to calculate the flow rate.
Modern flowmeters consist of a sensor that detects the physical values of the flowing medium and converts these into electrical signals, and a transmitter that processes this information. They are integrated into a threaded connection, or fitting, that connects them directly to the pipeline.
The transmitter converts the supplied signals – such as electrical voltage – into a standard signal. The flowmeter outputs this digitally or analogously via interfaces, depending on the device type. Flowmeters work according to various measurement principles. Some use electromagnetic technology, while other devices deploy surface acoustic waves or work as ultrasonic flowmeters.
The flow of liquids, gases or steam is always measured when the quantity of the flowing medium needs to be monitored or controlled. In water management, for example, flowmeters measure water in pipelines, open channels or treatment plants, thereby precisely determining consumption, flow rates or losses.
In many industrial processes, flowmeters measure the flow of the respective media before and after certain process steps. This allows flows in closed systems to be continuously monitored, ensuring the correct dosing, filling and mixing of liquids or gases. Flowmeters are key components when it comes to process reliability, efficiency and quality assurance.
Looking for some examples? Here are just a few of the common tasks and application areas that use flowmeters for monitoring and open-loop control:
Flowmeters are used in various industries such as pharmaceuticals and medical technology, food and beverages, and cosmetics. They are also very important for infrastructure, for example in municipal drinking water treatment or flow measurement in sewage treatment plants.
Which process is the right one for you? Find out in four steps with our guide and checklist for liquid flow measurement.
Our portfolio offers reliable and efficient flowmeters for virtually all areas of application in industrial processes. Below is an overview of the advantages and application areas for the different measurement principles.
+ Hygienic, thanks to non-contact measurement
+ Wear-free, as the measurement involves no moving parts
+ No pressure drop or loss, as the flowmeter has no constrictions
+ Compact compared to Coriolis flowmeters, therefore also suitable for use in machines and systems with limited space
+ Robust and reliable even with system vibrations and magnetic or electrical effects
+ Measurement performance is independent of the electrical conductivity of the medium
Added value thanks to multi-parameter measurement: With surface acoustic wave flowmeters, you can measure several parameters with a single device and special functions enable detection of gas bubbles and solid particles as well as changes between media.
SAW technology enables contactless measurement and is therefore particularly suitable for use in the pharmaceutical and biotechnology industries, as well as the food and beverages sector, where purity and hygiene play a crucial role. In the pharmaceutical industry, for example, water for injection (WFI) loops are equipped with this technology. These loops offer sophisticated treatment technology for the water circulating in a closed pipe system. In such circumstances, FLOWave flowmeters are deployed to ensure maximum sterility. In the food industry, SAW technology is used to monitor water-like liquids, such as in clean-in-place applications or other cleaning liquids, to ensure hygienic conditions at all times.
Bürkert offers two options that are suitable for different pipe diameters:
+ Long service life and low maintenance, as there are no moving parts in the measurement tube
+ Cost-effective and can be retrofitted (insertion)
+ High measurement stability and low sensitivity to inlet conditions (inline)
Flowmeters with electromagnetic measuring technology can be deployed in many areas of industry and infrastructure: from water management to the chemical and pharmaceutical industries and food production. However, accurate measurement results require a minimum conductivity of the medium to be measured of 5 μS/cm – i.e. 5 microsiemens per centimetre – and a certain degree of consistency in conductivity. Since parts of the flowmeter come into contact with the medium, the choice of a compatible material must be taken into account.
Depending on the design, the paddle wheel is either integrated into the fitting, i.e. the connecting piece between pipelines (inline), or, if required, is housed in a component of the transmitter and can thus also be retrofitted into existing pipelines (insertion).
+ Comparatively small and lightweight, making it suitable for compact systems and machines
+ Low energy consumption
+ Cost-effective technology
+ Conductivity of the medium is not a prerequisite for measuring accuracy
Important: various factors can affect the measuring accuracy of this mechanical flowmeter. For example, a certain minimum flow is required to set the paddle wheel in motion. Since they contain moving parts, paddle wheel flowmeters are not maintenance-free or wear-free. When installing in the pipe system, the inlet and outlet sections must also be taken into account.
The device is particularly suitable for low-solids, low-viscosity and at most slightly aggressive media. It is therefore frequently used as a flowmeter for water, both in water treatment applications and irrigation, as well as for cooling machinery in industrial processes.
+ Very accurate measurements, independent of flow velocity
+ No straight inlet and outlet sections required – compact installation
+ Robust and durable
As this mechanical flowmeter is based on the displacement principle, it measures grease, oil, honey, adhesive and other viscous media particularly efficiently. The measurement results are extremely accurate – provided that the flow rate and viscosity are sufficient and air bubbles are avoided.
+ Low-maintenance technology, thanks to the absence of moving parts
+ Suitable for conductive and non-conductive media
The time difference method is best suited for pure, homogeneous liquids and is used for irrigation, service water flow or heating and cooling in the metal industry. The accuracy of the measurement result also depends on the properties of the liquid.
If the flow of more contaminated liquids containing bubbles or particles needs to be measured, the Doppler method is recommended, as it relies on these suspended solids or bubbles for measurement.
+ Mass flow can be measured precisely, regardless of pressure or temperature fluctuations
+ Very fast response times due to low sensor mass
+ Low maintenance, thanks to the absence of moving parts
+ Compact design, easy device replacement with integrated configuration memory
Thermal flowmeters measure pure and mixed gases accurately and quickly. They are very versatile, with applications ranging from process gas monitoring in industrial contexts to compressed air consumption analysis or gas distribution systems (e.g. for nitrogen, oxygen or CO₂). Thanks to their compact design, thermal mass flowmeters can also be used in many applications in biotechnology and laboratory technology, as well as in exhaust gas and environmental measurement technology.
+ Very accurate measurement, large turndown ratio
+ Extremely stable, no zero point adjustment necessary even over long periods
+ Highly resistant materials even in contact with aggressive media
+ Wide range of application areas
Flowmeters with Coriolis technology are naturally sensitive to vibrations, so precise and tension-free installation is essential for accurate measurement results.
Do you need to precisely measure and control small quantities of liquid as well as recording other values such as the density or temperature of the medium? If so, the mass flowmeter with Coriolis technology is a good solution for you. It is frequently used in applications in the chemical and pharmaceutical industries, battery and semiconductor manufacturing, food technology and in laboratories – in other words, wherever small quantities need to be controlled and dosed precisely.
There is an ideal flowmeter for every scenario, and choosing the right model can be crucial to the precision and efficiency of your processes. At Bürkert, you will find a tailor-made and comprehensive solution for almost any application, as our selection of different measuring technologies is able to meet all kinds of individual requirements in terms of measuring accuracy, output and input signals, and area of application.
Our experts will be happy to answer all your questions around choosing the right flowmeter for your application. Why not get in touch!
