I’ve discussed how I volunteer in previous blogs. Sometimes it is during work hours, others, it is outside and on the weekends. The men’s group that I am part of at church has a smaller offshoot that goes out into our community and helps however possible. The name of our group is B4. It stands for Barbecue, Beer, Bible and Brotherhood. Four things most men appreciate, and again we call it B4 for short. My nerd-self argues it should be B 4. One of the projects we just wrapped up in our local community was for an organization called BLOC at their HOH facility. More acronyms. The HOH stands for Horses On the Hill and is a horse farm that is in an urban setting. This has working gardens that they sell fruit and vegetables to the community from, as well as a working horse farm where members learn how to care for the animals and ride, as well as work on some of their own items. While this blog isn’t about horse farms, it is about acronyms and how they can easily get thrown around when dealing with compressed air and air compressors. The picture is from our last day working there when we were wrapping up some trim work and watching a storm roll in. (Now tell me you’re from the MidWest with a single picture. )
Acronyms are something that comes with almost any field of study or professional position. Professionals everywhere love to use them and many even use them with redundant words. In my previous life, I took care of MSDS for the shop I worked in. What is MSDS? Material Safety Data Sheet is what it stands for, and any chemical should have one of these to accompany it in order to know how to handle the chemical safely. Even something like a window cleaner has one. It’s very easy to ask for an MSDS Sheet on a chemical, see that redundant word there? Times have changed, and now they are known as SDS, Safety Data Sheets. Still the same premise and still just as valuable when trying to be safe. When it comes to efficiency, though, acronyms used with redundant words are just not as efficient. You know that EXAIR is all about efficiency, and we deal with quite a few acronyms, so let’s talk about how we can ensure efficiency and lack of redundancy can be used when dealing with some of our acronyms.
CFM is the most basic one out of the bunch. It stands for Cubic Feet per Minute, and it is a unit of flow over time. This flow rate is generally used when dealing with gases, hence why we use it when talking about airflow, and really plays into many aspects of our products as well as the compressed air system in a facility. The metric equivalent is often M3/min. which, for an engineer-minded person, is easier to decipher, which doesn’t help a lot. It stands for Cubic Meters per Minute and is used by everyone else in the world outside the US. Both of these units of measure are thrown around a lot in the industry though, when a different unit is actually needed in order to meet the information needed.
CFM (M3/min.) is often stated when someone may actually be looking for SCFM, which is Standard Cubic Feet per Minute. This can also be a confusing unit, as the unit revolves around a reference point in order to be able to adapt it to your point of use conditions. We use a “Standard” condition that is accepted in the industry and that is 14.5 PSIA at 69° F and 0% RH. The Ideal Gas Law is used quite a bit to help determine how the RH, temperature, and pressure all affect the volume of the gas in question.
The least used version is ACFM, which is Actual Cubic Feet per Minute and is the ACTUAL flow rate under the conditions at the point of use. If we look at the horse farm mentioned above, on that day our relative humidity was through the roof while the temperature was low, so our volume would be impacted. While you believe this may be what you need more, generally it all has to be taken to standard conditions in order to calculate across different items anyway.
The newest of the acronyms is ICFM which is based around the Inlet Cubic Feet per Minute for the air’s conditions prior to entering the compressor at all. This, again, has to do with ACFM because it is at a specific pressure, relative humidity, and temperature.
The largest benefit to discussing consumption or flow rates with any Application Engineer at EXAIR is that we know the math behind converting each of these units of measure and can often get you the information you need right then and there as you talk with us. If you have some acronym fatigue from not knowing which to use, or you are trying to determine what the “Actual” output of your compressor is, contact one of our team members today.
Brian Farno, MBA – CCASS Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF