Earth Boring Drill Bits Made From A Low-Carbon, High-Molybdenum Alloy

• US 20090008154A1
• Filed: 07/02/2008
• Published: 01/08/2009
• Est. Priority Date: 07/02/2007
• Status: Active Grant

• Current Assignee: Baker Hughes Holdings LLC (Baker Hughes Company)
• Original Assignee: Baker Hughes Incorporated (Baker Hughes Company)
• Inventors: Nguyen, Don Q., Bradford, John F. III, El Hakam, Carmel Z., Sullivan, Eric
• Granted Patent: US 7,905,301 B2
• Time in Patent Office: Days
• US Class Current: 175/425
• CPC Class Codes: C21D 9/22 for drills; for milling cutters; for machine cutting tools
• CPC Class Codes: C22C 38/02 containing silicon
• CPC Class Codes: C22C 38/04 containing manganese
• CPC Class Codes: C22C 38/06 containing aluminium
• CPC Class Codes: C22C 38/44 with molybdenum or tungsten

Abstract

An earth boring bit formed from an alloy comprising a low carbon content and high molybdenum content is disclosed herein. The molybdenum content is greater than about 0.8% to about 1.15% by weight of the alloy. The carbon content may range up to about 0.16% by weight of the alloy. The alloy may further comprise alloy further comprises manganese, phosphorus, sulfur, silicon, nickel, chromium, copper, aluminum, vanadium, and calcium; with the balance being iron. The alloy experiences a relatively flattened hardenability curve and low martinsite formation.

Claims

1. A device for use in earth boring operations comprising:

an earth boring bit having at least a portion thereof formed from a steel alloy comprising, molybdenum in a weight percent of the alloy greater than about 0.8% and carbon in a weight percent of the alloy up to about 0.16%.

2. The device of claim 1, wherein the alloy comprises molybdenum in an amount of from about 0.82% to about 1.15% by weight.

3. The device of claim 1, wherein the alloy comprises molybdenum in an amount of from about 0.85% to about 1.12% by weight.

4. The device of claim 1, wherein the alloy comprises molybdenum in an amount of from about 0.9% to about 1.1% by weight.

5. The device of claim 1 wherein the alloy comprises carbon in an amount of from about 0.01% to about 0.15% by weight.

6. The device of claim 1 wherein the alloy further comprises manganese, phosphorus, sulfur, silicon, nickel, chromium, copper, aluminum, vanadium, calcium, and iron.

7. The device of claim 6, wherein the alloy comprises manganese in an amount of about 0.70% to about 1.00% by weight, phosphorus having a content up to about 0.035% by weight, sulfur having a content up to about 0.005% by weight, silicon ranging from about 0.15% to about 0.35% by weight, nickel ranging from about 1.65% to about 2% by weight, chromium ranging from about 0.45% to about 0.65% by weight, copper having a content of up to about 0.35% by weight, aluminum ranging from about 0.02% to about 0.45% by weight, vanadium ranging up to about 0.01% by weight, and calcium ranging up to about 0.003% by weight.

8. The device of claim 7, wherein the balance of the alloy comprises iron.

9. The device of claim 1, the earth boring bit comprising, a body having a bit leg;

a cone rotatably mounted to the bit leg, a drill string connection, and teeth formed on the cone, wherein at least one of the body, the bit leg;

the cone, the drill string connection, or teeth comprise the alloy.

10. The device of claim 1, wherein the bit body comprises the steel alloy.

11. An earth boring bit comprising:

a body having a bit leg;

a cone rotatably mounted to the bit leg; and

teeth formed on the cone, wherein at least one of the body, the bit leg;

the cone, or teeth include a steel alloy comprising, molybdenum in a weight percent of the alloy greater than about 0.8% and carbon in a weight percent of the alloy up to about 0.16%.

12. The earth boring bit of claim 11, wherein the alloy comprises molybdenum in an amount of from about 0.82% to about 1.15% by weight.

13. The earth boring bit of claim 11, wherein the alloy comprises molybdenum in an amount of from about 0.85% to about 1.12% by weight.

14. The earth boring bit of claim 11, wherein the alloy comprises molybdenum in an amount of from about 0.9% to about 1.1% by weight.

15. The earth boring bit of claim 11, wherein the alloy comprises carbon in an amount of from about 0.01% to about 0.15% by weight.

16. The earth boring bit of claim 11, wherein the alloy further comprises manganese, phosphorus, sulfur, silicon, nickel, chromium, copper, aluminum, vanadium, calcium, and iron.

17. The earth boring bit of claim 16, wherein the alloy comprises manganese in an amount of about 0.70% to about 1.00% by weight, phosphorus in an amount up to about 0.035% by weight, sulfur in an amount up to about 0.005% by weight, silicon in an amount ranging from about 0.15% to about 0.35% by weight, nickel in an amount ranging from about 1.65% to about 2% by weight, chromium in an amount ranging from about 0.45% to about 0.65% by weight, copper in an amount of up to about 0.35% by weight, aluminum in an amount ranging from about 0.02% to about 0.45% by weight, vanadium in an amount ranging up to about 0.01% by weight, and calcium in an amount ranging up to about 0.003% by weight.

18. The earth boring bit of claim 11, included with a drilling system and disposed on a lower end of a drill string, where the drill string is driven by a top drive.

19. A method of making an earth boring device comprising:

forming an earth boring bit wherein at least a portion of the bit is made from an alloy comprising molybdenum in a weight percent of the alloy greater than about 0.8% and carbon in a weight percent of the alloy up to about 0.16%.

20. The method of claim 19, wherein the alloy comprises molybdenum in an amount of from about 0.82% to about 1.15% by weight.

21. The method of claim 19, wherein the alloy further comprises manganese, phosphorus, sulfur, silicon, nickel, chromium, copper, aluminum, vanadium, calcium, and iron.