Reciprocating Compressor: Capacity

[keerthivasan81]

I am a bit confused with terms that define the capacity of a reciprocating compressor. While mostly the compressors are specified in terms of FAD (standard or actual), some manufactures specify compressor capacity at a certain pressure. Is the pressure referred above the maximum discharge pressure?
I have a compressor whose capacity rating is 18 CFM at 12 Ksc. (Receiver volume: Around 250 lit). My process application requires 15-20 CFM at 5 Ksc. Application: Continuous for 4 hrs. per day
I would like to know whether my compressor is sufficient to meet my above process needs.
Also does the compressor discharge flow rate vary with the pressure employed during the application ?
Is there any means to measure the air consumption rate (without flow meters)?
Thanks in advance for the replies..

 

[quark]

I would like to know whether my compressor is sufficient to meet my above process needs. - Yes, with the given data
Also does the compressor discharge flow rate vary with the pressure employed during the application ? - No
Is there any means to measure the air consumption rate (without flow meters)? - You can do it from receiver filling time, approximately

 

[keerthivasan81]

Thanks for taking time in replying my queries.

 

[Compositepro]

The capacity of piston compressors does decrease with increasing discharge pressure, due to volume in the cylinder that is not displaced by the piston. For this reason, most small compressors will give a capacity at 45 psi and at 90 psi.