WELL PUMP

摘要

A well pump includes a piston and an outlet valve assembly of special structure. Each is formed of a block of organic polymer, preferably PTFE. Each includes a cavity in its upper portion and passages leading from the cavity to the bottom of the block. A screen covers each cavity and a valve disk covers each screen. Flexible sealing flanges extend upwardly and downwardly from the periphery of the piston block. The valve block has a sliding and sealing fit with the piston rod.