Below motor equalizer of electrical submersible pump and method for connecting

Patent metadata

Field	Value
Publication number	US-9995118-B2
Application number	US-201514690041-A
Country	US
Kind code	B2
Filing date	Apr 17, 2015
Priority date	Jul 16, 2014
Publication date	Jun 12, 2018
Grant date	Jun 12, 2018

Abstract

Upper and lower pressure equalizers couple to a lower end of a motor of an electrical submersible pump assembly. An intermediate connection having a liquid flow passage connects the pressure equalizers. A connection valve located in the liquid flow passage closes the liquid flow passage prior to connecting the pressure equalizers with each other, and opens the liquid flow passage after the connection between the pressure equalizers is made. A sensor lower equalizer wire extends from a sensor unit through the lower pressure equalizer to a lower electrical terminal at the upper end of the lower pressure equalizer. A sensor upper equalizer wire connects to the lower electrical terminal and extends through the upper pressure equalizer to an upper electrical terminal at the upper end of the upper pressure equalizer. A sensor motor wire extends downward from the motor into engagement with the upper electrical terminal.

First claim

The invention claimed is:

1. An electrical submersible pump assembly, comprising:
a pump;
a motor having a rotatable shaft extending along a longitudinal axis and operatively coupled to the pump for driving the pump;
an upper pressure equalizer coupled to a lower end of the motor;
a lower pressure equalizer, each of the pressure equalizers having a movable equalizing element that communicates well fluid pressure exterior of the pressure equalizers to motor lubricant in the motor;
a connection between an upper end of the lower pressure equalizer and a lower end of the upper equalizer;
a liquid flow passage in the connection through which a liquid in the upper pressure equalizer communicates with a liquid in the lower pressure equalizer;
at least one connection valve located in the liquid flow passage that closes the liquid flow passage prior to connecting the pressure equalizers with each other, and opens the liquid flow passage after the connection between the lower pressure equalizer and the upper pressure equalizer is made;
wherein the connection comprises:
an upper pressure equalizer lower adapter secured to a lower end of the upper pressure equalizer;
a lower pressure equalizer upper adapter secured to an upper end of the lower pressure equalizer; wherein:
the liquid flow passage extends through the upper pressure equalizer lower adapter and through the lower pressure equalizer upper adapter;
the at least one valve comprises an upper pressure equalizer lower valve and a lower pressure equalizer upper valve;
the upper pressure equalizer lower valve being axially movable within the liquid flow passage in the upper pressure equalizer lower adapter and spring biased downward from an open position to a closed position, the upper pressure equalizer valve having an upper portion with an outer diameter that seals to the liquid flow passage while in the closed position, the upper pressure equalizer valve having a lower portion that has a smaller outer diameter than the upper portion and is surrounded by an annular clearance in the liquid flow passage in the upper pressure equalizer lower adapter both while in the closed position and while in the open position, the lower portion having a lower end that protrudes below a lower end of the upper pressure equalizer lower adapter while in the closed position; and
the lower pressure equalizer upper valve being axially movable within the liquid flow passage in the lower pressure equalizer upper adapter and spring biased upward from an open position to a closed position, the lower pressure equalizer valve having a lower portion with an outer diameter that seals to the liquid flow passage in the lower pressure equalizer upper adapter while in the closed position, the lower pressure equalizer valve having an upper portion that has a smaller outer diameter than the lower portion of the lower pressure equalizer valve and is surrounded by an annular clearance in the liquid flow passage in the lower pressure equalizer upper adapter both while in the closed position and while in the open position, the upper portion of the lower valve having an upper end that protrudes above the lower pressure equalizer upper adapter while in the closed position.

2. An electrical submersible pump assembly, comprising:
a pump;
a motor having a rotatable shaft extending along a longitudinal axis and operatively coupled to the pump for driving the pump;
an upper pressure equalizer coupled to a lower end of the motor;
a lower pressure equalizer, each of the pressure equalizers having a movable equalizing element that communicates well fluid pressure exterior of the pressure equalizers to motor lubricant in the motor;
a connection between an upper end of the lower pressure equalizer and a lower end of the upper equalizer;
a liquid flow passage in the connection through which a liquid in the upper pressure equalizer communicates with a liquid in the lower pressure equalizer;
at least one connection valve located in the liquid flow passage that closes the liquid flow passage prior to connecting the pressure equalizers with each other, and opens the liquid flow passage after the connection between the lower pressure equalizer and the upper pressure equalizer is made; wherein the connection comprises:
an upper pressure equalizer lower adapter secured to the lower end of the upper pressure equalizer;
a lower pressure equalizer upper adapter secured to the upper end of the lower pressure equalizer; wherein
the liquid flow passage extends through the upper pressure equalizer lower adapter and through the lower pressure equalizer upper adapter;
the at least one connection valve comprises an upper pressure equalizer lower valve and a lower pressure equalizer upper valve;
the upper pressure equalizer lower valve is mounted in the liquid flow passage in the upper pressure equalizer lower adapter and spring biased downward to a closed position protruding from a lower end of the upper pressure equalizer lower adapter;
the lower pressure equalizer upper valve is mounted in the liquid flow passage in the lower pressure equalizer upper adapter and spring biased upward to a closed position protruding from an upper of the lower pressure equalizer upper adapter; and wherein
the upper pressure equalizer lower valve and the lower pressure equalizer upper valve are radially offset from each other relative to the axis such that they do not contact each other when the lower pressure equalizer upper adapter is secured to the upper pressure equalizer lower adapter.

3. The assembly according to claim 2 , wherein:
the movable equalizing element within each of the upper and lower pressure equalizers comprises a bellows;
motor lubricant in fluid communication with the motor lubricant in the motor is located within an interior of the bellows of the upper pressure equalizer;
a secondary liquid is located on an exterior of the bellows of the upper pressure equalizer and an interior of the bellows of the lower pressure equalizer, the secondary liquid on the exterior of the bellows of the upper pressure equalizer being in fluid communication with the secondary liquid in the interior of the bellows of the lower pressure equalizer; and
the bellows of the lower pressure equalizer is adapted to be immersed in well fluid.

4. The assembly according to claim 2 , further comprising:
a motor equalizer adapter between an upper end of the upper pressure equalizer and a lower end of the motor;
a motor equalizer passage in the motor equalizer adapter for the passage of motor lubricant between the motor and the upper pressure equalizer;
a motor equalizer valve in the motor equalizer passage that is movable between an open position and a closed position; and wherein
an end portion of the shaft is in engagement with the motor equalizer valve while the motor equalizer valve is in a closed position; and
the motor equalizer valve is movable from the closed position to an open position in response to rotation of the shaft.

5. The assembly according to claim 2 , further comprising:
a sensor unit mounted to a lower end of the lower pressure equalizer;
a sensor lower equalizer line extending from the sensor unit through the lower pressure equalizer to a lower terminal at the upper end of the lower pressure equalizer;
a sensor upper equalizer line releasably connected to the lower terminal and extending through the upper pressure equalizer to an upper terminal at an upper end of the upper pressure equalizer; and
a sensor motor line extending downward from the motor and in releasable engagement with the upper terminal.

6. The assembly according to claim 2 , further comprising:
a sensor unit mounted to a lower end of the lower pressure equalizer;
a sensor lower equalizer wire extending from the se

Assignees

• Baker Hughes Inc
• Baker Hughes A Ge Co Llc

Inventors

• Tanner David
• Meyer Aron M
• Poretti Arturo Luis
• Semple Ryan P

Classifications

• F04D13/10

  adapted for use in mining bore holes · CPC title

• E21B43/128 Primary

  Adaptation of pump systems with down-hole electric drives · CPC title

• F04D13/062

  pressure compensation between motor- and pump- compartment · CPC title

• F04D29/061

  especially adapted for liquid pumps · CPC title

• E21B4/003

  Bearing, sealing, lubricating details (for roller bits E21B10/22) · CPC title