HYDRAULIC OIL WELL PUMPING APPARATUS

摘要

A hydraulic oil well pumping apparatus utilizing a hydraulic cylinder hav ing a piston or rod that is movable between upper and lower piston positions . A pumping string or sucker rod extends downwardly from the piston, the pum ping string or sucker rod being configured to extend into an oil well for pu mping oil from the well. A prime mover such as an engine is connected to a c ompensating type hydraulic pump, a directional control valve moves between o pen flow and closed flow positions and a hydraulic flow line connects the pu mp and the hydraulic cylinder. Electronic controls are provided that control movement of the piston as it moves between the upper and lower positions.