Hydraulic well pump

摘要: A hydraulic well pump for operating a sucker rod string including cylinder assembly raising and lowering the fluid counterbalancing system offsetting combined weight of reciprocating service equipment, column above plunger, string. One embodiment includes an air supported piston on movable exposed to chamber below functioning independently power logic pump. Another uses accumulator connected into supercharging pumps during lift stroke providing opposing force downstroke. Also disclosed are: length multiplier apparatus multi-layered strip metal tension member; sensor control adjusting end limits lengths; controlling acceleration deceleration.