Wellbore pump
AssigneeNatural Lift Systems Inc.
InventorDan Lee
Life of this patent
Estimating the term…
Abstract
The wellbore pump of the present invention comprises a plunger having passage means which may be open or closed by a valve operated by a piston which is biased in the open position by a spring of selected strength such that the wellbore pressure may overcome the spring to close the valve when the accumulated hydrostatic pressure reaches a certain value. When the valve closes the reservoir pressure forces the plunger to the surface and causes the accumulated liquids to be pumped out of the wellbore. A stem extending from the top of the piston engages a top plate and causes the valve to open when the plunger reaches the top of the wellbore. Means is provided whereby the valve opens when it reaches the top of the wellbore and a latch may be provided to retain the plunger from returning to the bottom of the well.
Claims11
A wellbore pump comprising:
- a plunger of generally cylindrical proportion adapted to fit within the internal dimensions of said wellbore;
- seal means on the outside of said plunger adapted to seal the space between said plunger and said wellbore;
- passage means in said plunger to allow fluid in said wellbore to pass through said plunger;
- a valve means in said passage movable between an open position and a closed position;
- a piston connected to said valve to open and close said valve;
- said piston being located in a cylinder chamber having spring means acting on the chamber side of said piston to bias said piston in a direction to open said valve;
- said piston being exposed to wellbore hydrostatic pressure on the side of said piston opposite to said spring.
Dependencies are inferred from the claim text.