Flow rates indicated on chart were determined by pumping water. For optimum life and performance, pumps should be specified so that daily operation parameters will fall in the center of the pump performance curve. 1 Displacement per storke was calcualted at 70 psig (4.8 bar) air inlet pressure against a 30 psig (2 bar) head pressure Example: To pump 7.6 lpm (2 gpm) against a discharge pressure head of 2.8 bar (40 psig) requires 4.1 bar (61 psig) and 1.2 Nm3 /h (.7 scfm) air consumption. (See dot on chart). Caution: Do not exceed 8.6 bar (125 psig) air supply pressure.