Milking cows by machine has become a standard procedure. The vacuum required to do the job can vary greatly depending on the number of cows to be milked. The entire milking procedure must be completed within two hours. In addition to transporting the milk, the vacuum used in these milking systems performs other tasks as well, such as attaching onto the udder and holding the weight of the milking claw assembly to the teat. NASH pumps offer significant advantages over oil-lubricated pumps because they use no oil, are tolerant of carryover, and require very little maintenance.