Imagine for a moment, you’ve spent a significant amount of time doing research on various gas flow measurement products, and believe you have found the product that meets your needs. However, after implementing and using your gas flow product, you realize it is not suitable for the application you specifically needed it for. What do you do now?

In a previous blog post, we discussed the key factors that should be considered when you are trying to determine whether or not a liquid flow sensor will work with a specific type of liquid. The three factors were the viscosity and transparency of the fluid, how hazardous the chemicals in the sample are and the flow range needed from the flow sensor.

To ensure engineers and technicians can use the gas flow products they need for their application, there are two key factors that must be considered to determine if a particular gas sample will work a gas flow sensor: the aggressiveness (hazardous) and specific gravity/density of the gas.

Aggressive Gases in Flow Sensors

The first key factor to consider is how aggressive the gas is. For example, if a gas is highly poisonous, the customer must take that into consideration when evaluating gas flow sensors. Additionally, if the gas has hazardous properties it could affect the material of the gas flow sensor. For instance, if the O-rings or other parts need to be changed to something that’s not susceptible to the gas, then the gas flow senor may not work at all for the desired application.

How Dense is your Gas Sample?

The second key factor to consider is the density of the gas that will be passing through the flow sensor.

Gas flow sensors can be used to measure different gases usually calibrated for air. A flow of air gives a certain response, and when you flow another gas through the flow sensor, its response will be different because of the gas’s density.

The output of the thermal mass flow sensor is directly related to the specific heat characteristic of the gas being measured. Therefore, if a unit is calibrated for air, it is a relatively simple calculation to figure the calibration for nitrogen or some other similar gas. This advantage offers flexibility not found on many other types of flow sensors. However, because thermal-type flow sensors are sensitive to the density of the material being measured, any impurities such as moisture can also affect the output.

In addition, if the density of the gas you need to measure is too dense, it may not be applicable to use for the gas flow sensor.

Accurate Gas Flow Measurement for Various Applications

Because of the compact size and economical cost of McMillan’s gas flow measurement products, gas flow sensors are suitable for a wide variety of industrial, commercial, laboratory and O.E.M. applications such as:

  • Gas consumption measuring
  • Compressor or pump output monitoring
  • Verification of sample gas streams
  • And more!

Before you invest your next gas flow sensor, remember to consider these two factors to ensure you’re getting the most out of your gas flow product!