Plunger lift separation and cycling

A plunger lift for a well producing through a production string communicating with a hydrocarbon formation, comprising a free piston having at least two sections, movable independently downwardly in the well, the sections comprising a lower component and a sleeve providing a seating surface for receiving the lower component so the lower component and sleeve join together in the well for pushing liquid, above the piston, upwardly and a catcher assembly on the well at the surface comprising a housing, a separator rod in the housing for receiving the sleeve thereon and dislodging the lower component, the housing, rod and sleeve providing therebetween flow passages for formation contents producing a pressure drop sufficient to hold the sleeve in the housing against gravity, the housing providing a path of falling movement for the sleeve to fall into the production string, the catcher assembly being free of components extending into the path of falling movement for retaining the sleeve in the housing.

A plunger lift well head assembly for a well producing through a production string communicating with a hydrocarbon formation, comprising

• a housing having an inlet at an end for receiving flow from the formation and an outlet spaced from the end;
• a separator rod in the housing having a free end pointed in the direction of the inlet for receiving a sleeve of a multipart piston and dislodging a lower component of the piston, the separator rod, the housing and the sleeve providing flow passages to the outlet, at least one of the flow passages being of variable cross-sectional size producing a pressure drop sufficient to hold the sleeve in the housing against gravity.

A plunger lift well head assembly for a well producing through a production string communicating with a hydrocarbon formation, comprising

• a housing having an inlet at an end for receiving flow from the formation and an outlet spaced from the end;
• a separator rod in the housing having a free end pointed in the direction of the inlet for receiving a sleeve of a multipart piston and dislodging a lower component of the piston, the separator rod, the housing and the sleeve providing flow passages to the outlet, at least one the flow passages having a first section and a second section, more restricted than the first section, the second section being below the first section so that upon a lessening of flow through the housing, the sleeve moves downwardly from the first section to the second section and decreases a flow passage thereby maintaining a pressure drop across the sleeve sufficient to hold the sleeve against gravity.

A method of lifting liquids from a well producing hydrocarbons from a formation through a well head with a plunger lift having a multipart piston including an upper sleeve and a lower component and a decoupler on the well head for separating the piston into its parts comprising a rod for receiving the sleeve and dislodging the lower component, comprising:

• holding the sleeve in the decoupler by passing formation contents upwardly;
• and then
• releasing the sleeve and allowing it to fall into the well by restricting flow of formation contents.

The method of lifting liquids from a well producing hydrocarbons from a formation through a well head with a plunger lift having a multipart piston movable upwardly in the well for pushing liquid, above the piston, upwardly, and a catcher on the well at the surface for receiving and holding at least a part of the piston against gravity for a selected time, comprising

• detecting liquid flow out of the well;
• and
• dropping the piston part into the well in response to detecting liquid flow.