Patent attributes
A plunger lift system has a bumper and a landing positioned in tubing below a safety valve of a well. A plunger moving between the bumper and landing lifts columns of liquid above the plunger when pushed by downhole pressure. A valve on the plunger's housing is movable between open and closed positions to either permit or prevent flow through the plunger. When the plunger engages the landing, a striker rod on the landing opens the valve permitting fluid communication through the plunger to a sales line at the surface. The valve is biased to the closed position to prevent fluid communication through the plunger. When the plunger is disengaged from the striker rod, the valve closes so that application of downhole pressure can again move the plunger uphole. A controller cycles the plunger between the bumper and the landing by controlling fluid flow in the well.