Abstract: A seal section for use in a downhole submersible pumping system includes a housing and a seal bag located within the housing. The seal bag includes a substrate having a plurality of substrate surfaces and a metal coating layer on at least one of the plurality of substrate surfaces. The substrate can optionally be configured as a cylindrical form that includes an interior surface and an exterior surface. In particularly preferred embodiments, the substrate is seamless and fabricated from an extruded fluoropolymer. The metal coating layer preferably comprises a metal selected from the group consisting of titanium, stainless steel, nickel, chrome, silver and gold. The metalized seal bag exhibits increased durability and decreased permeability to liquids and gases at elevated temperatures.

Abstract: A mechanical seal has a stationary face and rotating assembly adjacent to the stationary face. The rotating assembly includes an upper bellows ring, a lower bellows ring and a runner between the lower bellows ring and the stationary face. A bellows extends between the upper bellows ring and the lower bellows ring. In preferred embodiments, the bellows is constructed from a perfluoroalkoxy polymer and is secured within the upper bellows ring and the lower bellows ring by a selected locking mechanism. The locking mechanism may include the use of crimp rings configured for a press fit engagement within the upper and lower bellows rings. Alternatively, the locking mechanism may employ locking rings configured for threaded engagement with the upper and lower bellows rings.

Abstract: A method for applying a metalized polymer film to a seal bag for use in a downhole submersible pumping system includes the steps of applying a metal layer to a polymer layer, applying an adhesive layer to the polymer layer, and rolling the adhesive layer onto a substrate of the seal bag. The method may also include the steps of rotating a first roller, which is located above the polymer layer of the metalized polymer film, and rotating a second roller, which is located on an interior surface of the substrate of the seal bag, in the opposite direction of the first roller. Also disclosed is a downhole pumping system that incorporates a seal bag manufactured from these techniques.

Abstract: Disclosed is a change-over selector with a vacuum arc extinguishing circuit, including a central shaft, a moving contact driven by the central shaft to rotate, and a first static contact and a second static contact circularly arranged on insulation laths of a cage body of the change-over selector, where the moving contact is driven by the central shaft to rotate to switch between the first static contact and the second static contact, the moving contact and the first and second static contacts form a change-over selection main-circuit, a vacuum arc extinguishing sub-circuit including a vacuum tube is connected in parallel to the change-over selection main-circuit, the vacuum tube is opened after the moving contact is separated from the first static contact, and the vacuum tube is closed before the moving contact is electrically connected to the second static contact.

Abstract: A downhole pumping system includes a motor, a pump driven by the motor and a seal section positioned between the pump and the motor. The seal section preferably includes a first seal bag assembly, a second seal bag assembly and an interconnect module connected between the first seal bag assembly and the second seal bag assembly. The interconnect module includes a plenum, at least one fluid exchange passage connected to the plenum, and a shaft seal assembly. The shaft seal assembly is configured to divert fluid from the plenum into the at least one fluid exchange passage. In another aspect, a first group of interconnect modules within the seal section each includes a shaft seal assembly oriented in a first direction and a second group of the interconnect modules each includes a shaft seal assembly oriented in a second direction to selectively apply an axial force on the shaft.

Abstract: An agitator assembly for use in a gas separator includes a central hub and at least one blade affixed to the central hub. The blade includes a leading end, a trailing end, a first curved portion adjacent to the leading end and a second curved portion adjacent to the trailing end. In a particularly preferred embodiment, the first and second curved portions are substantially parabolic and have foci on opposite sides of the blade.

Abstract: A gas separator is configured to separate gas from a two-phase fluid. The gas separator includes a rotatable shaft, a plurality of separation stages and an outer housing. Each of the plurality of separation stages includes a rotor connected to the rotatable shaft, a diffuser downstream from the rotor and a crossover downstream from the diffuser. Each crossover is configured to remove gas from its respective separation stage. The outer housing includes a separate group of discharge ports for each separation stage to permit the removal of gas from each separation stage.

Abstract: A seal section for a downhole pumping system includes a fluid exchange pathway and a rotatable gravity separator. The rotatable gravity separator preferably includes a chamber, a backwash inlet connecting the chamber to the fluid exchange pathway and a backwash outlet connecting the chamber to the fluid exchange pathway. The rotatable gravity separator further includes a weight that causes the rotatable gravity separator to remain in a substantially constant orientation with respect to the force of gravity.

Abstract: A seal section for a downhole pumping system includes a fluid exchange pathway and a rotatable gravity separator. The rotatable gravity separator preferably includes a chamber, a backwash inlet connecting the chamber to the fluid exchange pathway and a backwash outlet connecting the chamber to the fluid exchange pathway. The rotatable gravity separator further includes a weight that causes the rotatable gravity separator to remain in a substantially constant orientation with respect to the force of gravity.

Abstract: Disclosed is a submersible pumping system for pumping wellbore fluids. The submersible pumping system includes a motor assembly, a pump assembly connected to the motor assembly, and a shroud assembly attached to the pump assembly. The shroud assembly includes a shroud having a connection end and an intake end. The shroud assembly at least partially encloses the motor assembly and includes a sealing ring adjacent the shroud prevents the wellbore fluid from entering the shroud at the connection end. The shroud assembly also preferably includes a retaining ring that holds the sealing ring in place.

Abstract: Disclosed is a submersible pumping system for pumping wellbore fluids. The submersible pumping system includes a motor assembly, a pump assembly connected to the motor assembly, and a shroud assembly attached to the pump assembly. The shroud assembly includes a shroud having a connection end and an intake end. The shroud assembly at least partially encloses the motor assembly and includes a sealing ring adjacent the shroud prevents the wellbore fluid from entering the shroud at the connection end. The shroud assembly also preferably includes a retaining ring that holds the sealing ring in place.