Abstract: A downhole valve for insertion in a production tubing string permits recirculation of fluid pumped into the casing annulus. The valve includes a cylindrical housing defining an opening, an internal mandrel disposed within the housing, defining a central bore and defining an opening, a valve between the housing and the mandrel, wherein said valve opens to allow fluid communication from the mandrel central bore to the annulus space in response to a pressure differential between the mandrel central bore and the annular space, and biasing means for biasing the valve in a closed position. The valve may be set within a completion string by wireline techniques.

Abstract: An intermittent lift plunger includes at least one seal mandrel, a bottom sub and an upper valve assembly. The valve assembly is closed by a well bottom stop which inserts into the lift plunger and opened by a lubricator stop at the top of the well. The seal mandrel includes a sleeve seal formed from an elastomeric rubber or plastic, which inflates to engage the well bore surface when the valve is closed and a pressure differential exists.

Abstract: A master ball valve with an integrated main hanger below the valve which may be used to hang jointed tubing, coil tubing, or electrified coil tubing for connection with an electric submersible pump.

Abstract: A bottom hole assembly for an intermittent lift plunger system includes a retrievable downhole anchor which may be set and reset in one downhole trip, a retrievable packing device, and a plunger stop.