Computer-controlled and motorised adjustable flow-rate gas lift valve

摘要

An adjustable flow-rate gas lift valve comprises a electric motor (12) connected by a shaft (20) to a ball screw (18) and a ported sleeve (28) threadably attached to the lower end of the ball screw. Power is supplied by a electric line (10) to the motor which turns the ball screw through gear box (16) transferring axial movement to the ported sleeve. Downward movement of the ported sleeve brings ports (32) into alignment with the main annulus opening (34) which allows well fluid to flow into chamber (26) of housing (24). The inward fluid flow is dependent on the number of ports (32) uncovered. Fluid pressure in chamber (26) unseats check valve (36) which is biased by spring (40) allowing fluid to flow out of access opening (38) into, for example, a production tubing string. An alternative method of altering fluid flow is by varying the size of the ports on the ported sleeve and having correspondingly sized openings to the annulus. Further embodiments include use of a reservoir, a pump and a bladder or piston-actuated check balls to cover annulus ports, a series of identical or varied valves operated by a computer, a helical valve member or a remotely controlled fluid/gas regulator.