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How High Lifters Work

High Lifter Pumps - How Do They Work?

The High Lifter is a double-acting, reciprocating differential piston, fluid-powered pressure intensifier.

It transfers the energy from a larger volume of low-pressure liquid to a smaller volume of liquid, imparting to it higher pressure. This pumps the smaller volume under high pressure.

The degree of pressure intensification that the High Lifter provides depends on the volumetric ratio of the pump: the ratio of the area of its large piston to the area of its small piston.


The High Lifter works as a kind of hydraulic lever.

PI = Inlet Pressure
PO = Outlet Pressure
AI = Inlet Piston Area
AO = Outlet Piston Area

PI x AI = PO x AO

Your specific needs will determine the pump ratio selected. This ratio will in turn determine the percentage of inlet flow being pumped. High Lifter model H74 is available in volumetric ratios from 2:1 to 22:1. The smaller models H44 or H49 are 4.5:1 and 9:1, respectively.

Because of their design, High Lifter pumps can be readily converted from one ratio to another.