Cutting structures and structures for retaining the same

• US 9,482,058 B2
• Filed: 06/11/2014
• Issued: 11/01/2016
• Est. Priority Date: 06/12/2013
• Status: Active Grant

• Current Assignee: Smith International Incorporated (Schlumberger NV)
• Original Assignee: Smith International Incorporated (Schlumberger NV)
• Inventors: Siracki, Michael A.
• Primary Examiner(s): Bomar, Shane
• Application Number:
  US14/302,119
• Publication Number:
  US 20140367174A1
• Time in Patent Office: 874 Days
• US Class Current: 1/1
• CPC Class Codes: E21B 10/573 characterised by support details, e.g. the substrate construction or the interface between the substrate and the cutting element
• CPC Class Codes: E21B 10/633 independently detachable

Abstract

A downhole cutting tool may include a tool body having at least one cutting element support structure formed thereon, wherein the at least one cutting element support structure comprises at least one cutter pocket formed therein; at least one cutter having at least substantially unobstructed cutting face retained within the at least one cutter pocket, the cutter pocket preventing substantial lateral movement of the at least one cutter; and at least one retention element interfacing a portion of a circumferential surface of the at least one cutter.

Claims

1. A downhole cutting tool, comprising:

a tool body having at least one cutting element support structure formed thereon, wherein the at least one cutting element support structure comprises at least one cutter pocket formed therein at a retention pocket radially adjacent to the at least one cutter pocket and intersecting a leading face of the at least one cutting element support structure;

at least one cutter, having a substantially unobstructed cutting face, retained within the at least one cutter pocket, the cutter pocket preventing substantial lateral movement of the at least one cutter; and

at least one retention element interfacing a partial circumferential surface of the at least one cutter of less than 180 degrees, wherein the retention element is disposed in the retention pocket.

2. The downhole cutting tool of claim 1, wherein the at least one cutter is a rolling cutter.

3. The downhole cutting tool of claim 1, wherein an exposed face of the at least one retention element is substantially flush with the substantially unobstructed cutting face of the at least one cutter.

4. The downhole cutting tool of claim 1, wherein the retention element comprises a thru-hole therein, and is retained by a fastener extending through the thru-hole.

5. The downhole cutting tool of claim 1, wherein the retention element limits axial movement of the cutter in at least one axial direction.

6. The downhole cutting tool of claim 1, wherein the at least one retention element is brazed in place.

7. The downhole cutting tool of claim 1, wherein the at least one retention element comprises at least two pieces interfacing a side surface of the at least one cutter.

8. The downhole cutting tool of claim 2, further comprising at least one fixed cutting element, wherein each fixed cutting element is disposed in one of the cutter pockets.

9. The downhole cutting tool of claim 2, wherein the downhole cutting tool is a fixed cutter bit comprising a bit body and a plurality of blades extending from the bit body, wherein the at least one cutter pocket is formed in one of the plurality of blades.

10. A downhole cutting tool, comprising:

a tool body having at least one cutter pocket and at least one retention pocket formed therein, the at least one retention pocket being radially adjacent to and intersecting a portion of the at least one cutter pocket;

at least one rolling cutter retained in the at least one cutter pocket, the at least one rolling cutter having a circumferential groove formed in a circumferential surface of the at least one rolling cutter; and

at least one retention element retained in the at least one retention pocket, the at least one retention element having a substantially mating geometry with a portion of the circumferential groove of the at least one rolling cutter, the retention element comprising a thru-hole therein, the retention element being retained by a fastener extending through the thru-hole.

11. The downhole cutting tool of claim 10, wherein the at least one retention element interfaces a partial circumference of the at least one rolling cutter by less than 180 degrees.

12. The downhole cutting tool of claim 10, wherein an exposed face of the at least one retention element is substantially flush with a cutting face of the at least one rolling cutter.

13. The downhole cutting tool of claim 10, wherein a cutting face of the at least one rolling cutter is substantially unobstructed.

14. The downhole cutting tool of claim 10, wherein the retention pocket intersects a leading face of at least one cutting element support structure of the tool body.

15. The downhole cutting tool of claim 10, wherein the retention element limits axial movement of the rolling cutter in at least one axial direction.

16. The downhole cutting tool of claim 10, wherein the at least one retention element is brazed in place.

17. The downhole cutting tool of claim 10, wherein the at least one retention element comprises at least two pieces interfacing a side surface of the at least one rolling cutter.

18. The downhole cutting tool of claim 10, further comprising at least one fixed cutting element, wherein each fixed cutting element is disposed in one of the cutter pockets.

19. The downhole cutting tool of claim 10, wherein the downhole cutting tool is a fixed cutter bit comprising a bit body and a plurality of blades extending from the bit body, wherein the at least one cutter pocket is formed in one of the plurality of blades.

20. A fixed cutter downhole tool, comprising:

a body;

a blade extending from the body, the blade having a leading face, a cutter pocket intersecting the leading face, and a retention pocket radially adjacent to the cutter pocket and intersecting the cutter pocket and the leading face;

a cutter retained in the cutter pocket, the cutter having a cutting face that is substantially unobstructed and exposed to formation to be drilled; and

a retention element retained in the retention pocket and securing the cutter to the blade, the retention element interfacing the blade and a geometry of the cutter.

21. The fixed cutter downhole tool of claim 20, wherein the retention element:

(a) includes a thru-hole and is secured to the blade by a fastener extending through the thru-hole;

(b) interfaces the geometry of the cutter around a partial circumferential surface of less than 180 degrees of the cutter;

or

(c) both (a) and (b).