Air Products Home

Ask the Experts Metals

I know my flowmeter tells me that I have a certain gas flow rate, but how can I be sure?

Flowmeters must be sized properly for each particular application, type of gas, gas pressure, and operating range. First, make sure that your flowmeter is calibrated for the specific gravity of the gas that you are metering. Check the label or the glass tube of the flowmeter or call the manufacturer to be sure. Second, operate the flowmeter only at the pressure for which it was calibrated. As an example, a variable-area flowmeter calibrated for 80 psi and reading 1000 scfh will really only be delivering 760 scfh if it is operated at 40 psi. This is a 24% error! Third, for best accuracy and to allow room for adjustment, size the flowmeter so that your normal flow rate falls within 30%–70% of full scale. These three steps will help ensure that you have good control over your gas flows and, ultimately, your process.

For a free copy of Gas Atmosphere Analysis Guidelines, please call 800-654-4567.
← Back to Iron and Steel Production
An error has occured, please fix the highlighted fields.
To request a quote or for more information about Air Products, please fill out the form below, and an Air Products representative will contact you shortly.
Please use the form below to contact us.

What can we answer for you?

  1. What kind of inquiry?

If you would prefer to contact us by phone, you can call any of our Air Products locations worldwide by visiting Worldwide Locations & Phone Numbers.


This site uses cookies to store information on your computer. Some are essential to make our site work; others help us to better understand our users. By using the site, you consent to the placement of these cookies. Read our Legal Notice to learn more.