Parts Dept Milking Machines

How Many CFM ? 3A Recommendations. Calculating CFM

The vacuum pump must remove as much air from the milking system as is admitted to it under any circumstances. Actual milking requires about 2 CFM (ASME) per milker, but a reserve is needed to cover vacuum needed for attaching the milker, inflation slips and fall-off. Fall-off is the single biggest draw on vacuum, needing from 10 to 40 CFM (ASME) to keep the other milkers stable. Attaching the milker and liner slips draw 2 to 5CFM (ASME) each. These non-milking vacuum drains are averaged out across all the milkers in a pipeline to reach the recommendations of the National 3A Accepted Practices Committee listed below.

Components	3A Recommended Vacuum CFM (ASME)
Per Milker Unit	6
Per Milk Meter	1
Vacuum Regulator	3
Per 10 Milk Inlets	1
Per Detacher	0*

*Detachers use approximately one (1) CFM (ASME) during the 2 seconds of retraction. This negligible usage is covered under Per Milker Unit in the
table above.

Example of a calculation of 3A recommended vacuum requirements for a double 6 milking parlor with milk meters and detachers.	Components	CFM (ASME) per Unit	CFM (ASME) Total
	12 milker units w/pulsators	6 per unit	72 CFM (ASME)
	12 milk meters	1 per meter	12
	1 vacuum regulator	3 per regulator	3
	24 inlets (milk & pulsation)	1 per 10 inlets	3
	12 detachers	0 per detacher	0
	Total 3A Recommended Vacuum		90 CFM (ASME)

ONE IMPORTANT NOTE: The 3A recommendations assume the proper size balance tank, milk and vacuum lines and properly functioning pulsation and milkers. If an actual system is deficient in any of these areas, the 3A
recommendations may fall short of actual requirements.