Electrical submersible pump with single direction lubricant flow

Patent metadata

Field	Value
Publication number	US-12480498-B2
Application number	US-202318484650-A
Country	US
Kind code	B2
Filing date	Oct 11, 2023
Priority date	Oct 12, 2022
Publication date	Nov 25, 2025
Grant date	Nov 25, 2025

Abstract

An electrical submersible pumping system (“ESP”) for use in a wellbore includes an electrical motor, a pump, a shaft coupled between the motor and pump, and a lubricant pump for circulating lubricant within the ESP. The lubricant pump includes a diffuser and an impeller that mounts onto and rotates with shaft rotation. A portion of the impeller has a frusto-conical outer surface, which is circumscribed by a portion of the diffuser profiled complementary to the frusto-conical portion of the impeller. The pump directs lubricant flow in a single direction irrespective of the rotational direction of the shaft.

First claim

What is claimed is:

1 . An electrical submersible pump assembly (“ESP”) comprising:
a motor;
a pump connected to the motor by a shaft;
a seal section; and
a lubricant pump comprising,
a diffuser having an axial bore with sidewalls that are oriented generally oblique to an axis of the shaft and that define a frusto-conical flow section within the diffuser, and
an impeller having an axis and a portion with a frusto-conically shaped outer surface that is disposed within the flow section, so that when the impeller is rotated about the axis and with respect to the diffuser, a lubricant flow is induced along the flow section.

2 . The ESP of claim 1 , wherein the outer surface of the portion of the impeller defines a pumping section.

3 . The ESP of claim 2 , wherein the diffuser comprises an upstream portion, a mid-portion, and a downstream portion that are axially adjacent one another, and wherein a port is formed radially through the upstream portion through which lubricant flow is induced by relative rotation of the impeller and diffuser.

4 . The ESP of claim 2 , further comprising elongated ribs on the pumping section that extend along a line that intersects an axis of the shaft, wherein slots are formed between adjacent ribs.

5 . The ESP of claim 2 , wherein a taper of the pumping section varies with a taper of the flow section.

6 . The ESP of claim 4 , wherein one or more of a width, a length, and a height of the ribs varies.

7 . The ESP of claim 1 , further comprising elongated ribs formed on the sidewalls of the diffuser.

8 . The ESP of claim 1 , wherein the impeller is mounted to the shaft.

9 . The ESP of claim 1 , further comprising a thrust bearing assembly that is coupled to the shaft and in the path of the lubricant flow.

10 . The ESP of claim 1 , wherein the impeller outer surface is dimpled with indentations.

11 . The ESP of claim 1 , wherein the lubricant pump is formed using an additive manufacturing process.

12 . The ESP of claim 11 , wherein the lubricant pump comprises materials selected from the group consisting of plastic injection materials, PTFE, and molecularly imprinted polymer, metal, plastic, and combinations thereof.

13 . The ESP of claim 11 , wherein the lubricant pump is assembled in the seal section as a separate insert and a stationary insert is combined with a bearing retainer.

14 . The ESP of claim 13 , wherein the stationary insert and bearing retainer are monolithic.

15 . An electrical submersible pump assembly (“ESP”) comprising:
a motor;
a pump connected to the motor by a shaft;
a seal section; and
a lubricant pump comprising,
an amount of fluid lubricant,
a diffuser having an axial bore, and
an impeller disposed in the bore, the diffuser and impeller configured to rotate relative to one another in a clockwise direction and in a counterclockwise direction, and when rotating to induce a flow of the lubricant in an axial direction when rotation is clockwise, and in the same axial direction when rotation is counterclockwise.

16 . The ESP of claim 15 , wherein the bore and an outer surface of the impeller are frusto-conically shaped.

17 . The ESP of claim 15 , further comprising ribs on an outer surface of the impeller.

18 . The ESP of claim 15 , wherein the diffuser comprises an upstream portion, a mid-portion, and a downstream portion that are axially adjacent one another, and wherein a port is formed radially through the upstream portion through which lubricant flow is induced by relative rotation of the impeller and diffuser.

Assignees

• Baker Hughes Oilfield Operations Llc

Inventors

• Howell Steven Alan
• Tanner David

Classifications

• F04D29/2283

  for reverse pumping action · CPC title

• F04D29/2255

  flow-channels with a special cross-section contour, e.g. ejecting, throttling or diffusing effect · CPC title

• F04D29/245

  for special effects · CPC title

• F04D1/04

  Helico-centrifugal pumps · CPC title

• F04D29/183

  Semi axial flow rotors · CPC title