ABSTRACT
When an operator chooses a high pressure system, the most important decision will normally be to choose the size and type of pump unit to be used. The second choice will be in terms of the delivery circuit through which the pump will send the water, under pressure, to the operating tool (Fig. 2.1). The tool will, in turn, direct this water to either one or several jet nozzles. At the nozzle the water flow is restricted to a small diameter and directed out, through an orifice at the work surface. The operator should decide what size of pump and parts to use, based upon the need for a given amount of delivered power at the working surface.
