Can someone explain "CFM" ?

[50:1]

Regarding blowers, I know the higher the cfm at the pipe the better. But, what is cfm. The density of the air? What current is to voltage?

 

[asb151]

Cubic feet per minute. Volume per unit time.

 

[sedanman]

Manufacturers that can't make horsepower try to impress you with mph. I have to explain at least once a week why a certain blower with 250 mph air is a piece of junk and one with 180 mph but more cfm is better.

 

[mbopp]

Yup, cubic feet per minute. Trivia - "Standard" CFM or SCFM is corrected to 30.00" barometric pressure & 70deg F temperature IIRR. I used to test fans, blowers & transport systems in a past life......

 

[Goliath]

A cubic foot of air per minute through any device (blower, compressor, etc) is 1 CFM. That same amount of air, even after it is compressed, is a Standard Cubic Foot (even though it takes up less room than 1 CF after being compressed). 1 CFM and 1 SCFM are the same amount of air if there is no compression (i.e you are not squeezing the air into a pressurized tank). 1 CFM is more than 1 SCFM if you are talking about the outlet flow of a compressor that is discharging into a 100 psi tank. Compressors are commonly rated at X SCFM at Y psi (for instance 9.5 SCFM at 120 psi). Leaf blowers are rated simply with CFM ratings (for instance 200 CFM). Therefore, when you are talking about a leaf blower, you talk about CFM. The air is not compressed; it is just moved. You should look for a unit with a high CFM rating as opposed to a high speed rating. When you are talking about an air compressor, you look for a high SCFM rating, as this compensates for different outlet pressures. I hope this helps, but I don't know where your question is comming from. Here is a picture of my eight-legged cat at suppertime.

 

[Chainsaw Master]

Manufacturers that can't make horsepower try to impress you with mph. I have to explain at least once a week why a certain blower with 250 mph air is a piece of junk and one with 180 mph but more cfm is better.

Thats kinda the same scam that digital camera makers use...they say select picture Quality....good...better....best, when its really size, in pixles, and nothing to do with quality....