When you are working with certain liquids, such as gas or oil, it is important to know exactly how much you are working with. You can gauge how much you are using by using a mass flow meter. Mass flow meters, however, only monitor the fluid density, or mass, and not the volume.
If you need to know the volume of the gas or oil, or whatever other liquid or substance you may be using, you will typically make use of a mass air flow meter, which will give you the volume based on how much air is passing through the intake. This is especially important in such devices as car engines and other combustion engines.
Mass flow meters are typically designed and used by engineers. They are designed for the strict purpose of measuring exactly how much fluid you are moving through the tubes you're using. They work by slowly twisting depending on how much fluid passes through the mass flow meters.
Without mass flow meters, and mass air flow meters, it would be hard to gauge how much fluid you were working with. This would be very important when working with combustible fluids or very expensive fluids. Engineers are paid to be exact in their measurements and in their designs and that's one of the reasons why they created the mass flow meter.
A mass flow meter can be small and can be used in simple car engines, or in even small engines such as lawn mower engines, or they can be used on a larger scale, say, at an oil plant. A mass flow meter can save money on a grand scale by revealing exactly how much fluid is passing through the tubes. So, if you are using oil, which is extremely valuable, you would want to know exactly how much you're working with. You wouldn't want any to be wasted. For that reason, and for many others, a mass flow meter becomes extremely necessary.
Another great reason for mass flow meters is that they can save lives. When you're working with fluids that react badly when mixed, or just volatile fluids in general, you want to be precise in how much you're using and how much is passing through the tubes you're monitoring. For this reason, mass flow meters are extremely useful and can prevent many accidents. As can be seen, flow meters are useful not only in saving money but also in preventing accidents, which is essential to any business or personal user.