A sealing device includes a plurality of non-contact seals provided along a sealed shaft; a contact seal provided on at least one of two sides of the plurality of non-contact seals; an injection part that supplies purge gas into a first space of spaces arranged in an axial direction of the sealed shaft, the spaces being between the plurality of non-contact seals and the contact seal; and a collector that collects the purge gas from a second space of the spaces between the plurality of non-contact seals and the contact seal, the second space being positioned to be next to the first space in the axial direction.

The invention relates to a shaft bearing having a seal arrangement to prevent steam leakages that can occur in the event of temperature fluctuations or pressure fluctuations between a liquid medium on the one side and a gaseous medium on the other side of the compact bearing, wherein, between a primary radial seal and a rotation bearing portion, a lubrication space surrounding a shaft circumference is arranged that receives a volume of lubricating grease that has a higher viscosity than a lubricating oil and a coolant; and a volume compensator for compensating a temperature-dependent volume fluctuation is provided that comprises a compressible material, and is arranged vertically in interaction with the volume of the lubricating oil and/or the volume of the lubricating grease.

A technique facilitates controlling barrier fluid via a mechanical pressure regulation system which may be coupled with a rotating machine at a subsea location. The mechanical pressure regulation system enables controlled supply of the barrier fluid to the rotating machine and comprises a mechanical valve mechanism. The mechanical valve mechanism automatically maintains a pressure differential between the barrier fluid and a process fluid within a desired range. According to an embodiment, the mechanical valve mechanism is mechanically actuated via pressures applied to a pilot piston so as to provide barrier fluid to the rotating machine when the pressure differential reaches a lower limit and to dump barrier fluid when the pressure differential reaches an upper limit.

A submersible well fluid system for operating submerged in a body of water may include an electric machine and a fluid end. The electric machine includes a rotor and a stator residing in a first housing at specified conditions. The fluid end may include an impeller and be coupled to the electric machine. The submersible well fluid system may also include an adjustable speed drive for the electric machine in the housing. The submersible well fluid system may also include a chemical distribution system for supplying treatment chemicals to the submersible well fluid system, a barrier fluid supply system for supplying a barrier fluid to the submersible well fluid system, and a pressure management system.

A seal arrangement is described for providing a seal between a rotatable shaft and a housing having a wall through which the shaft extends. The seal arrangement includes, in series, a mechanical seal and a gland seal. The mechanical seal is positioned axially inwardly of the gland seal such that the mechanical seal forms a first stage or primary seal and the gland seal forms a secondary seal.

A technique facilitates controlling barrier fluid via a mechanical pressure regulation system which may be coupled with a rotating machine at a subsea location. The mechanical pressure regulation system enables controlled supply of the barrier fluid to the rotating machine and comprises a mechanical valve mechanism. The mechanical valve mechanism automatically maintains a pressure differential between the barrier fluid and a process fluid within a desired range. According to an embodiment, the mechanical valve mechanism is mechanically actuated via pressures applied to a pilot piston so as to provide barrier fluid to the rotating machine when the pressure differential reaches a lower limit and to dump barrier fluid when the pressure differential reaches an upper limit.

In centrifugal pumps and, in particular, pumps for transferring fluids containing abrasive particles such as slurry pumps, wear of wetted areas is a major maintenance issue. The invention provides for the protection of internal surfaces vulnerable to wear from such particles by providing means for adjusting and controlling distribution of gland fluid for flushing vulnerable areas. The invention extends to a method and a retrofit kit, but provides primarily for a centrifugal pump assembly comprising an impeller rotatably mounted therein and support means operatively arranged for supporting the impeller from its suction side in sealing relationship with the housing. The sealing means may be mechanically adjustable for substantially even distribution of gland fluid to both axial sides of the impeller in the pump housing.

The gas seal column pump may comprise a pump drive, a gas seal column with a corrosion resistant telescoping liner, a seal gas control box, and a pump. A drive motor of the pump drive, the gas seal column, and the pump may comprise a sealed, vertically-oriented, pumping system where the gas seal column is operable to replace mechanical seals around a drive shaft that couples the drive motor to the pump. A pressurized seal gas pumped into the gas seal column may displace corrosive fumes and the product being pumped. An unsealed pump drive motor may be used for certain applications. The vertical length of the telescoping liner may be controlled to mitigate interference with pump operation. Responsive to inputs from the level sensors, a seal gas control box may regulate the pressure of the seal gas using a plurality of valves.

An electrical submersible pump (ESP) isolates its motor lubricant from pumped product without requiring a bellows, diaphragm, bladder, or external lubricant pressurizing system. A pair of nested isolation chambers below the motor housing are filled with a barrier fluid that is non-reactive, non-miscible, and higher in density than the pumped product and the motor lubricant. As the motor lubricant expands and contracts after pump start-up and shut-down, motor lubricant and barrier fluid are exchanged between the motor housing and the isolation chambers via three interconnections, while pumped product is exchanged with the inner barrier chamber, while being isolated from the motor housing. The interconnections extend between the bottom of the motor housing and the bottom of the outer barrier chamber, between the top of the outer barrier chamber and the bottom of the inner barrier chamber, and between the top of the inner barrier chamber and the pumped product.

A submersible pump assembly includes a seal section connected to a motor, the seal section having a housing with an outboard bearing at a housing pump end in radial supporting engagement with a drive shaft. An inboard bearing is also in the housing pump end, axially spaced from the outboard bearing, and in radial supporting engagement with the shaft. A barrier fluid chamber in the housing pump end contains a barrier fluid. A primary shaft seal is located within the barrier fluid chamber and seals the barrier fluid in the barrier fluid chamber from the motor lubricant. A secondary shaft seal is mounted in the barrier fluid chamber between the primary shaft seal and the outboard bearing. The secondary shaft seal seals the barrier fluid in the barrier fluid chamber from well fluid exterior of the housing pump end.