Patterned texturing of the seal surface for a roller cone rock bit
View Patent ↗Surface texturing is employed to modify the topography of one or more surfaces (radial or cylindrical) of the sealing system for a roller cone rock bit. The surface texturing produces a regular or repeated patterned dimpled surface which retains additional lubricant helpful in reducing friction in the boundary and mixed lubrication regimes.
1. A sealing system for a bearing of a rock bit, comprising:
a gland;
a shaft; and
a seal positioned in the gland and compressed by the gland against the shaft at a sealing surface on the shaft,
wherein the sealing surface includes a surface texturing comprised of a plurality of non-overlapping surface texture features arranged in a repeating pattern, wherein the surface texture features are reservoir-like structure.
2. The sealing system of claim 1 , wherein the repeating pattern is an array pattern.
3. The sealing system of claim 1 , wherein the repeating pattern is an offset array pattern.
4. The sealing system of claim 1 , wherein the surface texture features have a uniform size and shape.
5. The sealing system of claim 1 , wherein surface texture features comprise dimples.
6. The sealing system of claim 5 , wherein the dimples have a circular plan shape.
7. The sealing system of claim 5 , wherein the dimples have an elliptical plan shape.
8. The sealing system of claim 1 , wherein the surface texture features have a uniform size and shape, and a depth of between 3 and 3000 microns.
9. The sealing system of claim 8 , wherein the depth is 20-30 microns.
10. The sealing system of claim 1 , wherein the surface texture features have a uniform size and shape, and a width or diameter of 15-1000 microns.
11. The sealing system of claim 10 , wherein the width or diameter is 100-200 microns.
12. The sealing system of claim 1 , wherein a density of textured surface area for the surface texture features is between 3-60%.
13. The sealing system of claim 12 , wherein the density of textured surface area is 15-20%.
14. The sealing system of claim 1 , wherein a percentage of the sealing surface covered with surface texture features is 3-100%.
15. The sealing system of claim 14 , wherein the percentage is greater than 60%.
16. The sealing system of claim 15 , wherein the percentage is about 100%.
17. The sealing system of claim 1 , wherein the sealing surface is a cylindrical surface of the shaft.
18. The sealing system of claim 1 , wherein the sealing surface is a conical surface of the shaft.
19. An apparatus, comprising:
a shaft including a first seal surface;
a roller cone having an annular gland including a second seal surface;
wherein the roller cone is rotatably mounted to the shaft such that the annular gland aligns with the first seal surface;
a seal ring compressed between the first and second seal surfaces within the annular gland; and
wherein at least one of the first and second seal surfaces includes a surface texturing comprised of a plurality of non-overlapping surface texture features arranged in a pattern which repeats along a circumference of the at least one of the first and second seal surfaces, the surface texture features being reservoir-like structure.
20. The apparatus of claim 19 , wherein the first seal surface includes the surface texturing and the first seal surface is a cylindrical surface.
21. The apparatus of claim 19 , wherein the first seal surface includes the surface texturing and the first seal surface is a conical surface.
22. The apparatus of claim 19 , wherein the second seal surface includes the surface texturing and the second seal surface is a cylindrical surface.
23. The apparatus of claim 19 , wherein the first seal surface includes the surface texturing and the second seal surface is a conical surface.
24. The apparatus of claim 19 , wherein the repeating pattern is an array pattern.
25. The apparatus of claim 19 , wherein the repeating pattern is an offset array pattern.
26. The apparatus of claim 19 , wherein the surface texture features have a uniform size and shape.
27. An apparatus, comprising:
a shaft including a first seal surface;
a roller cone having an annular gland including a second seal surface;
wherein the roller cone is rotatably mounted to the shaft such that the annular gland aligns with the first seal surface;
a seal ring compressed between the first and second seal surfaces within the annular gland; and
wherein at least one of the first and second seal surfaces includes a surface texturing comprised of a plurality of non-overlapping surface texture features arranged in a non-random pattern extending about a circumference of the at least one of the first and second seal surfaces, the surface texture features being reservoir-like structure.
28. The apparatus of claim 27 , wherein the at least one of the first and second seal surfaces is in sliding contact with the seal ring.