Patent ID: 6296052
Filing Date: 2001-10-02
Classification: E21B

Abstract:
An auxiliary fluid lift system for a well normally producing gas under greater than atmospheric pressure from a natural gas producing formation and having a string of casing depending from a well head, connected with a gas flow line, into a borehole admitting gas and fluid into the depending end portion thereof and having a string of tubing depending from the wellhead into the casing and supported at its depending end portion by a packer sealing with the inner wall surface of the casing above the entrance of gas and fluid and defining a casing annulus around the tubing communicating with the tubing interior adjacent the packer, the combination comprising:a plurality of pistons axially disposed in the depending end portion of the tubing and having axially connected piston rod means, vertically movable as a unit relative to the pistons, for admitting or blocking gas and fluid entry into the casing annulus;gas compressor means interposed between and communicating with the well head and the gas flow line through valve equipped conductors; and,control means including well head and flow line gas pressure sensing means connected with the compressor means and conductors for energizing said compressor means from a source of gas under pressure in response to a predetermined decrease of gas pressure in the well head or flow line and forcing gas under greater than atmospheric pressure into the tubing at the well head for forcing the piston rod means downwardly to close the gas and fluid entrance and force accumulated fluid from the casing annulus into the flow line.