With such a variety of flow meters available on the market – over 100 different types – it can be daunting when you embark on a flow meter selection process, but making sure that you choose the right one for your application is extremely important. We take a look at how to select the right flow meters and switches to ensure accurate outputs and reliable control.
The most common place that people start when looking at flow meter selection is usually with their own budget and therefore the price of a flow meter. Secondly, people tend to explore the most commonly used or popular flow meters within their industry. Whilst budget must be a realistic consideration, some of the higher priced options are low maintenance and provide better longevity, and therefore the initial outlay isn’t necessarily the full picture in terms of cost.
Many flow meters are designed for use in specific industries, and these are often a good place to start your research – but you must also consider the application demands when looking at flow meter selection because the specific requirements of your application and intended usage should ultimately dictate how to select the right flow meter and switch.
A flow meter reports the amount of media passing a point in a system. They are designed to be passive and manually checked by the user. A flow switch is, in effect, a flow meter with a sensor that can be used to trigger an external event based upon specified readings. When going through the process of flow meter selection, these are some of the areas that you will need to consider:
- What is the intended job of the flowmeter? Are you simply looking for a one-off measurement or continual monitoring of the flow rate within a system, or do you also want to control the flow based upon the output reading? The answer to these will help to guide you as to the kind of configuration that you need.
- What media are you measuring? You will need to consider whether your media flow is steam, gas or liquid, and, if it is a liquid, whether it is conductive and whether it is clean or dirty (slurry). For example, if you are looking to measure gas, you could opt for differential pressure, turbine or thermal mass flow meter (amongst others) but an ultrasonic or electromagnetic flow meter would not be suitable. Similarly, if your flow is corrosive or toxic, there will be safety considerations and you will want a flow meter that will not be damaged by your media flow.
- What are your operating parameters? You will need to look at the minimum and maximum pressures and temperature ranges as well as standard expected operating levels. Similarly, whether the flow is continuous or variable and whether inconsistencies such as pulsation, in-line air or slug flow is likely to be an issue.
- What output do you require? You will need to decide whether your information should be output in mass or volumetric units; the type and density of the flow will help to determine which would be most suitable. You may also be deciding between a digital or analogue flow meter and whether you need that information available to a shared source.
- Installation and location considerations. One of the key aspects to consider in flow meter selection is the area in which the flow meter is to be fitted; the available space, accessibility, pipe run length and whether it is up- or down-stream, amongst other things. If it is a hygienic processing application then it may be required to undergo harsh cleaning methods, or perhaps cannot come into contact with the media flow at all.
If you are looking for guidance on how to select the right flow meters and switches, then why not talk to BEST Pneumatic Systems? With over 30 years’ industry experience and a range of flow meters and flow switches, we are ideally placed to assist with flow meter selection for a wide range of applications. Call us now on 01254 395 000 or email [email protected] to speak to one of our experts.