Abstract: A plunger lift for a hydrocarbon well includes a piston that is dropped into the well and then moved upwardly to lift liquid to the surface from adjacent a hydrocarbon formation. The piston includes a series of pads biased outwardly into engagement with an inside wall of the production string thereby providing an improved seal between the piston and the production string. The pads are biased outwardly by pressure from below or a pressure differential that is moving the piston upwardly. The force moving the pads outwardly are greater during upward movement of the piston than during downward movement. The piston includes a central one-piece mandrel having an upper end higher than any component of the piston and a lower end lower than any component of the piston so that impact forces are applied directly to the mandrel and not through a threaded component.

Abstract: A plunger lift for a hydrocarbon well includes a piston that is dropped into the well and then moved upwardly to lift liquid to the surface from adjacent a hydrocarbon formation. The piston includes a series of pads biased outwardly into engagement with an inside wall of the production string thereby providing an improved seal between the piston and the production string. The pads are biased outwardly by pressure from below or a pressure differential that is moving the piston upwardly. The force moving the pads outwardly are greater during upward movement of the piston than during downward movement. The piston includes a central one-piece mandrel having an upper end higher than any component of the piston and a lower end lower than any component of the piston so that impact forces are applied directly to the mandrel and not through a threaded component.

Abstract: A plunger lift for a hydrocarbon well includes a multipart piston that is dropped into the well in separate pieces. When the pieces reach the bottom of the well, they fall into an accumulation of the formation liquid in the bottom of the well and unite. Gas from the formation pushes the unit upwardly, pushing liquid above the piston toward the surface. The multipart piston includes a upper sleeve and a lower component. A decoupler at the surface comprises a separator rod which the sleeve passes onto thereby dislodging the lower component and allowing it to fall into the well. The sleeve is held on the separator rod by the action of well contents flowing around and/or through the sleeve. When well flow around the sleeve is interrupted, the sleeve falls into the well. The length of time the sleeve is held at the surface is varied in response to the amount of liquid produced on each cycle.

Abstract: A plunger lift for a hydrocarbon well includes a multipart piston that is dropped into the well in separate pieces. When the pieces reach the bottom of the well, they fall into an accumulation of the formation liquid in the bottom of the well and unite. Gas from the formation pushes the unit upwardly, pushing liquid above the piston toward the surface. In one embodiment, the piston is made of a low density, high strength material such as silicon nitride and/or titanium alloys.

Abstract: A plunger lift for a hydrocarbon well includes a multipart piston that is dropped into the well in separate pieces. When the pieces reach the bottom of the well, they fall into an accumulation of the formation liquid in the bottom of the well and unite. Gas from the formation pushes the unit upwardly, pushing liquid above the piston toward the surface.

Abstract: A method and apparatus for pumping formation liquids provides a reciprocating down hole pump on the end of a coiled tubing string. In one embodiment, one fluid flow path is provided through the inside of the coiled tubing and another flow path is provided in an annulus between the coiled tubing and a, production string. In one embodiment, pressure delivered down the annulus to the pump moves a piston in a direction to move formation liquids upwardly to the surface. When pressure in the annulus is reduced, the hydrostatic weight of the pumped liquid moves the piston in a retracting direction to prepare for the next stroke. In other embodiments, the piston is moved downwardly, in retracting direction, by fluid pressure applied from the surface.