Double Sealing Labyrinth Chamber for Use With a Downhole Electrical Submersible Pump

An electrical submersible pump assembly disposable within a wellbore comprising:

• a motor;
• a pump coupled to the motor;
• a seal section housing between the pump and the motor;
• a chamber defined in the seal section housing;
• upper and lower guide members in opposing ends of the seal section housing, each having a central passage therethrough;
• an equalizing passage leading from the chamber to the motor;
• a shaft extending between the pump and the motor and through the central passages in the upper and lower guide members;
• an inner labyrinth seal assembly comprising an upper end in fluid communication with fluid in the central passage between the upper seal, an upper port in fluid communication with the chamber, and a looping flow path that extends axially along the shaft and radially between the upper end and upper port;
• and
• an outer labyrinth seal assembly comprising a looping flow path in the chamber having a first end in fluid communication with well fluid ambient to the pump assembly and a second end in fluid communication with the pressure equalizing passage for equalizing pressure of lubricant in the motor with well fluid.

An electrical submersible pump assembly disposable within a wellbore comprising:

• a motor;
• a pump coupled to the motor;
• a seal section housing between the pump and the motor;
• upper and lower guide members in the seal section housing, each having a central passage therethrough, defining a chamber in the seal section housing;
• an equalizing passage leading from the chamber to the motor;
• a shaft extending between the pump and the motor and through the central passages in the upper and lower guide members in the seal section housing;
• an upper seal between the passage of the upper guide member that seals around the shaft and seals well fluid from the chamber;
• and
• an inner labyrinth seal assembly comprising:
• an upper end coupled to the upper guide member and in fluid communication with fluid in the central passage between the upper seal,
• a lower end coupled to the lower guide member,
• an inner guide tube extending between the upper and lower guide members and circumscribing the shaft to define an annulus therebetween,
• a port formed through a side wall of the inner guide tube proximate the lower guide member,
• an outer guide tube extending between the upper and lower guide members and circumscribing the inner guide tube to define an annulus therebetween, and
• a port formed through a side wall of the outer guide tube proximate the upper guide member.