# Relationship between psi and cfm

### The Difference Between PSI And CFM

The notation CFM (Cubic Feet per Minute) refers to a volume of air produced by the air compressor at a given pressure or PSI (Pound per Square Inch). The right . Then you can figure the true CFM from the difference in starting and final pressures, In units of atmospheres of pressure, since 1 atm = psi, the 17 psi of . the regulator(s) and hose(s) between the tool and the compressor; these can rob. The relationship between CFM and PSI is just linear. Ie, if you charge to psi, and pull the electrical dayline.info you get 8 CFM at psi, you will get 4 CFM at.

Because production workers typically blow off their workstations between shift changes. What is the Relationship Between Flow and Pressure? A plant has a hp rotary screw compressor rated at acfm at psig.

However, they can only maintain 80 psig in the production area. How much more compressor hp does the plant need to maintain the required psig in the plant header? What is the Cost of Over-Pressurizing the System? The artificial demand in this case is 25 psig.

A rule of thumb to remember is that for every 2-psi increase in discharge pressure, the energy measured at the compressor goes up by 1 percent.

Obviously, there are pressure drops across the clean-up equipment dryers and filterswhich could equate to 10 to 15 psig or more.

### What is the difference between CFM and PSI? - Field Air Compressors

But if the system was properly sized and maintained, this should be easily factored into what to set the discharge pressure of the compressor. Assuming that the clean-up equipment and piping distribution system were poorly sized and maintained, which equates to a psig pressure drop, you could still cut the pressure on the compressor operating at psig to psig, and still maintain the desired 75 psig on the production floor. Dialing the pressure down by 25 psig, the plant could save To calculate the energy savings, use the energy equation below: To calculate kW, multiply BHP by the constant.

Typically compressor manufacturers utilize a 1.

Therefore, a hp rotary screw air compressor actually pulls on average BHP at full load, depending on the manufacturer. If the compressed air system was properly audited on the supply and demand side, which resulted in adding the proper amount of storage, pressure flow controller, etc.

Keep doing this over a period of time, and you will eventually have someone scream at you. Then turn it up 2 psig, and leave it alone. Another way to reduce leaks is to have a leak audit performed and implemented. This is why some manufacturers will post for example a capacity of 20 cfm at 90 psi and 18 cfm at psi for the same compressor. You cannot calculate it, you must measure it.

• What is the difference between PSI and CFM?
• The Relationship Between Pressure and Flow in a Compressed Air System
• Relationship between CFM vs PSI

So if you ask yourself "How much cfm my compressor will deliver if I use it at 50 psi and the manufacturer posted a capacity of 20 cfm at 90 psi?

Hope this info useful. Ok, I have it. Here's the basics the air flow and CFM are based upon three things: The larger the tank, the greater the supply of air longer supply of CFM for a more gradual drop in pressure. This is the "capacitor" or "flywheel" in the system.

However, this is only the "time" relationship. If you know your pressure and just want CFM, you don't care about the tank size. Separate the Tank from the compressor ie, compressor is off. Ie, if you charge to psi, and pull the electrical plug The pressure just "pushes" the air out, and with half the "push" you get half the air flow.

## Calculating CFM

The motor and compressor. A general rule of thumb is that a 5hp motor can produce 10 CFM at psi.

Ie, my old 2hp 20 gall compressor pulls about 6. Thats a power pull of watts. At about watts per HP, that's 2. Then, what you do is combine 2 and 3 above for a graph. This would not include a third axis time which would include bleed-out based on tank size.