Radial bearing thrust washer arrangement for submersible pump motor

Patent metadata

Field	Value
Publication number	US-9941770-B2
Application number	US-201414581095-A
Country	US
Kind code	B2
Filing date	Dec 23, 2014
Priority date	Dec 27, 2013
Publication date	Apr 10, 2018
Grant date	Apr 10, 2018

Abstract

An electrical submersible pump assembly has a motor that drives the pump. The motor has a stator having a bore, a shaft extending through the stator, and rotor sections mounted to the shaft, each of the rotor sections having first and second end rings. A non rotating bearing body has a periphery retained in non rotating engagement with the bore of the stator. The bearing body has a first end axially spaced from the first end ring, defining a first gap, and a second end axially spaced from the second rotor ring, defining a second gap. A first thrust washer is located in the first gap. Each thrust washer has a metal or carbide thrust surface for contact with the bearing body and an elastomeric thrust surface for contact with one of the end rings.

First claim

The invention claimed is:

1. An electrical submersible pump assembly, comprising:
a pump;
a motor operatively coupled to the pump for driving the pump, the motor comprising:
a stator having a bore;
a shaft extending through the bore along an axis of the motor;
first and second rotor sections mounted to the shaft for rotation therewith;
a sleeve mounted to the shaft between the first and second rotor sections for rotation in unison with the shaft;
a bearing body having a central opening receiving the sleeve and a periphery in non rotating engagement with the bore of the stator, the bearing body having a first thrust surface axially spaced from the first rotor section, defining a first gap, and a second thrust surface axially spaced from the second rotor section, defining a second gap;
a first thrust washer located in the first gap for transferring thrust between the first rotor section and the first thrust surface of the bearing body when the first gap narrows;
a second thrust washer located in the second gap for transferring thrust between the second rotor section and the second thrust surface of the bearing body when the second gap narrows;
each of the first and second thrust washers having a bearing body layer that engages one of the thrust surfaces of the bearing body and a rotor section layer that engages one of the rotor sections while transferring thrust, the bearing body layer and the rotor section layer of each of the first and second thrust washers being directly attached to each other; and
wherein the bearing body layer of each of the first and second thrust washers is harder than the rotor section layer of each of the first and second thrust washers.

2. The assembly according to claim 1 , wherein:
the bearing body layer of each of the first and second thrust washers comprises a metal or a carbide; and
the rotor section layer of each of the first and second thrust washers comprises an elastomer.

3. The assembly according to claim 1 , wherein:
a sum of an axial thickness of the first thrust washer plus an axial thickness of the second thrust washer is less than a sum of axial dimensions of the first and second gaps.

4. The assembly according to claim 1 , wherein a thrust surface area of a contacting portion of the rotor section layer of the first thrust washer with the first rotor section is greater than a thrust surface area of a contacting portion of the bearing body layer of the first thrust washer and the first thrust surface of the bearing body.

5. The assembly according to claim 1 , wherein
the bearing body layer of the first thrust washer has a smaller inner diameter than an inner diameter of the first thrust surface of the bearing body; and
the bearing body layer of the second thrust washer has a smaller inner diameter than an inner diameter of the second thrust surface of the bearing body.

6. The assembly according to claim 1 , wherein an inner diameter and an outer diameter of the bearing body layer of the first thrust washer are the same as an inner diameter and an outer diameter of the rotor section layer of the first thrust washer.

7. The assembly according to claim 1 , wherein:
an inner diameter of the first thrust washer is greater than an outer diameter of the sleeve.

8. The assembly according to claim 1 , wherein:
the sleeve has a first end in contact with the first rotor section and a second end in contact with the second rotor section; and
an axial length of the sleeve is greater than an axial distance between the first and second thrust surfaces of the bearing body plus axial thicknesses of the first and second thrust washers.

9. The assembly according to claim 1 , wherein:
the bearing body has a plurality of lubricant flow passages extending axially therethrough, the lubricant flow passages being spaced around the axis in an array at a selected radius from the axis; and
an outer periphery of each of the thrust washers is located a distance from the axis no greater than the radius of the array of lubricant flow passages.

10. An electrical submersible pump assembly, comprising:
a pump;
a motor operatively coupled to the pump for driving the pump, the motor comprising:
a stator having a bore;
a shaft extending through the bore along an axis of the motor;
first and second rotor sections mounted to the shaft for rotation therewith, the first rotor section having a first end ring axially spaced from a second end ring of the second rotor section;
a sleeve mounted to the shaft for rotation in unison, the sleeve having a first end in contact with the first end ring and a second end in contact with the second end ring, fixing an axial distance between the first end ring and the second end ring;
a bearing body having a central opening that receives the sleeve and a periphery retained in non rotating engagement with the bore of the stator, the bearing body having a first thrust surface axially spaced from the first end ring, defining a first gap, and a second thrust surface axially spaced from the second end ring, defining a second gap;
a first thrust washer located in the first gap, the first thrust washer having a metal or carbide layer for contact with the first thrust surface of the bearing body, the first thrust washer having an elastomeric layer for contact with the first end ring, the metal or carbide layer of the first thrust washer being directly attached to the elastomeric layer of the first thrust washer; and
a second thrust washer located in the second gap, the second thrust washer having a metal or carbide layer for contact with the second thrust surface of the bearing body, the second thrust washer having an elastomeric layer for contact with the second end ring, the metal or carbide layer of the second thrust washer being directly attached to the elastomeric layer of the second thrust washer.

11. The assembly according to claim 10 , wherein:
the first and second rotor sections are axially movable relative to the stator and the bearing body in response to thermal growth;
axial movement of the first and second rotor sections in a first direction narrows the first gap to an axial thickness of the first thrust washer and places the elastomeric layer of the first thrust washer in engagement with the first end ring and the metal or carbide layer of the first thrust washer in engagement with the first thrust surface of the bearing body to transfer thrust between the bearing body and the first rotor section; and
axial movement of the first and second rotor sections in the first direction also widens the second gap to a dimension greater than an axial thickness of the second thrust washer.

12. The assembly according to claim 10 , wherein:
the fixed axial distance between the first and second end rings is greater than an axial distance from the first thrust surface to the second thrust surface of the bearing body plus axial thicknesses of the first and the second thrust washers.

13. The assembly according to claim 10 , wherein:
a surface area of contacting portions of the elastomeric layer of the first thrust washer and the first end ring is greater than a surface area of contacting portions of the metal or carbide layer of the first thrust washer and the first thrust surface of the bearing body.

14. The assembly according to claim 10 , wherein the metal or carbide layer and the elastomeric layer of the first thrust washer have inner diameters that are the same and outer diameters that are the same.

15. The assembly according to claim 10 , wherein a sum of axial dimensions of the first and second gaps is greater than a sum of an axial thickness

Assignees

• Baker Hughes Inc
• Baker Hughes A Ge Co Llc

Inventors

• Rumbaugh Michael R
• Clingman James Christopher

Classifications

• H02K5/132

  Submersible electric motors (H02K5/128 takes precedence) · CPC title

• H02K7/08 Primary

  Structural association with bearings · CPC title

• H02K5/167

  using sliding-contact or spherical cap bearings · CPC title