Protected back-up rings for metal face seals and earth boring tools incorporating the same

Patent metadata

Field	Value
Publication number	US-12188300-B2
Application number	US-202318189900-A
Country	US
Kind code	B2
Filing date	Mar 24, 2023
Priority date	Mar 24, 2023
Publication date	Jan 7, 2025
Grant date	Jan 7, 2025

Abstract

An earth-boring rotary drill tool may comprise a body comprising a pin, a roller cone mounted on the pin, and a seal assembly disposed between the pin and the roller cone. The first ring may comprise longitudinally converging sidewall surfaces defining a minimum radial thickness of the first ring at points of tangential intersection with a convex curved surface spanning a radial thickness of the first ring. The second ring may comprise a concave surface located and configured to interface over an area of contact with the convex curved surface of the first ring. The third ring may be positioned adjacent to, and concentric with, the second ring. The second ring may be disposed radially inward from the third ring. The first ring may also contact a surface of the roller cone or an insert ring adjacent the roller cone to form a seal between the first ring and the surface.

First claim

What is claimed is:

1. A seal assembly for an earth-boring tool, the seal assembly comprising at least three rings, the at least three rings comprising a first ring, a second ring, and a third ring;
the first ring comprising longitudinally converging sidewall surfaces defining a minimum radial thickness of the first ring at points of tangential intersection with a convex curved surface spanning a radial thickness of the first ring;
wherein the second ring is located and configured to interface with the convex curved surface of the first ring to form a seal; and
wherein the third ring is adjacent to, and concentric with, the second ring, the second ring being disposed radially inward from the third ring.

2. The seal assembly of claim 1 , wherein the second ring comprises a concave surface located and configured to interface over an area of contact with the convex curved surface of the first ring to form the seal.

3. The seal assembly of claim 2 , wherein a curvature of the convex curved surface of the first ring and a curvature of the concave surface of the second ring are at least substantially complementary.

4. The seal assembly of claim 1 , wherein the second ring and the third ring each comprise an axial thickness, wherein the axial thickness of the third ring is at least substantially equal to the axial thickness of the second ring.

5. The seal assembly of claim 1 , wherein the first ring comprises a metal material.

6. The seal assembly of claim 1 , wherein the second ring comprises an elastomer.

7. The seal assembly of claim 6 , wherein the elastomer comprises nitrile butadiene rubber (NBR).

8. The seal assembly of claim 1 , wherein the third ring comprises a plastic material or a metal material.

9. The seal assembly of claim 1 , wherein the convex curved surface comprises a radius of curvature within a range of 15% to 40% of a maximum radial thickness defined by the longitudinally converging sidewall surfaces.

10. An earth-boring rotary drill tool, comprising:
a bit body comprising at least one bearing pin;
at least one roller cone rotatably mounted over the at least one bearing pin; and
at least one seal assembly disposed between the at least one bearing pin and the at least one roller cone, the at least one seal assembly comprising at least a first, second, and third ring;
the first ring comprising:
interior and exterior sidewall surfaces, wherein a distance between the interior and exterior sidewall surfaces defines a radial thickness of the first ring,
a distal surface proximate a surface of the at least one roller cone to form a seal between the distal surface of the first ring and the surface of the at least one roller cone, and
a proximal surface spanning the radial thickness of the first ring, wherein the proximal surface is generally U-shaped, and the interior and exterior sidewall surfaces tangentially intersect the proximal surface;

the second ring comprising an incurvated surface, located and configured to interface with the proximal curved surface of the first ring;

wherein the third ring is adjacent to, and concentric with, the second ring, the second ring being disposed radially inward the third ring; and
wherein the first, second, and third rings remain stationary relative to the at least one bearing pin as the at least one roller cone rotates about the at least one bearing pin.

11. The earth-boring rotary drill tool of claim 10 , wherein a curvature of the proximal surface of the first ring and a curvature of the incurvated surface of the second ring are substantially complementary.

12. The earth-boring rotary drill tool of claim 10 , wherein the second ring and the third ring each comprise an axial thickness, wherein the axial thickness of the third ring is at least substantially equal to the axial thickness of the second ring.

13. The earth-boring rotary drill tool of claim 10 , wherein the first ring comprises a metal material.

14. The earth-boring rotary drill tool of claim 10 , wherein the second ring comprises an elastomer.

15. The earth-boring rotary drill tool of claim 14 , wherein the elastomer comprises nitrile butadiene rubber (NBR).

16. The earth-boring rotary drill tool of claim 10 , wherein the third ring comprises a plastic material or a metal material.

17. The earth-boring rotary drill tool of claim 10 , wherein the proximal surface comprises a radius of curvature within a range of 15% to 40% of a maximum radial thickness of the first ring.

18. The earth-boring rotary drill tool of claim 10 , wherein the third ring is bonded to the second ring.

19. The earth-boring rotary drill tool of claim 10 , wherein the second ring is configured to be at least partially compressed by the first ring, wherein the second ring, when at least partially compressed by the first ring, biases the distal surface of the first ring against the surface of the at least one roller cone.

20. A method of assembling a seal assembly for an earth-boring rotary drill tool, the method comprising:
positioning a first ring adjacent a base of a bearing pin carried by a body of an earth-boring rotary drill bit, wherein a first surface of the first ring contacts an area of a surface of the bearing pin;
positioning a second ring adjacent the base of the pin and adjacent the first ring;
positioning a third ring adjacent to, and radially outward from, the first ring, wherein the third ring is concentric with the first ring; and
translating a roller cone towards the base of the bearing pin along an axis of the pin to mount the roller cone on the bearing pin, wherein a first surface of the second ring contacts an area of a surface of the roller cone, and wherein translating the roller cone biases a generally U-shaped second surface of the second ring onto a concave second surface of the first ring, wherein a curvature of the concave second surface of the first ring is complementary to a curvature of the generally U-shaped second surface of the second ring.

Assignees

• Baker Hughes Oilfield Operations Llc

Inventors

• Ricks Gregory L
• Schroder Jon David

Classifications

• E21B10/25 Primary

  characterised by sealing details · CPC title