Hybrid bit with mechanically attached roller cone elements

Patent metadata

Field	Value
Publication number	US-10107039-B2
Application number	US-201514720189-A
Country	US
Kind code	B2
Filing date	May 22, 2015
Priority date	May 23, 2014
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

A modular hybrid drill bit is disclosed comprising a plurality of fixed blades and at least one rolling cutter assembly that is mechanically fastened to a bit body by a plurality of mechanical fasteners. The at least one rolling cutter assembly can be adjusted to change the axial and radial exposure of the rolling cutter elements.

First claim

What is claimed is:

1. A hybrid drill bit comprising:
a body having a plurality of blades, each blade comprising a plurality of earth formation cutting elements;
at least one rolling cutter assembly pocket formed into the body and comprising a first torque-reacting structure, wherein the pocket is disposed between adjacent blades;
at least one rolling cutter assembly comprising a head onto which a cutter element is rotatably coupled;
the head comprising a second torque-reacting structure configured to operatively engage the first torque-reacting structure and a plurality of mechanical fastener openings;
the head adjustably positioned axially and radially in the pocket to establish a predetermined rolling cutter exposure;
a plurality of mechanical fasteners configured to securely and removably couple the at least one rolling cutter assembly to the pocket in the predetermined rolling cutter exposure position;
a locking structure formed on a portion of at least one fastener and configured to provide an interference fit between the locking structure and an associated fastener opening in the head;
a plurality of locking caps, each locking cap being configured to engage an exposed portion of a respective fastener to prevent relative rotation between the fastener and the locking cap; and
a plurality of weldments engaging at least a portion of each locking cap, the plurality of weldments configured to prevent dislodgment of each locking cap from the respective fastener and to prevent relative rotation between each locking cap and the body, each weldment of the plurality of weldments being disposed between adjacent locking caps of the plurality of locking caps and joining the adjacent locking caps of the plurality of locking caps.

2. The hybrid drill bit of claim 1 , wherein the first and second torque-reacting structures comprise a tongue and groove configuration.

3. The hybrid drill bit of claim 1 , wherein the fastener openings are substantially round and configured for a location fit with a portion of the mechanical fastener.

4. The hybrid drill bit of claim 1 , wherein a portion of at least one mechanical fastener is configured for an interference fit with a fastener opening.

5. The hybrid drill bit of claim 4 , wherein the interference fit causes deformation in the fastener opening.

6. The hybrid drill bit of claim 5 , wherein the deformation in the fastener opening secures the head in an axial location.

7. The hybrid drill bit of claim 1 , further comprising at least one shim between the at least one rolling cutter assembly and the pocket to change an axial rolling cutter exposure.

8. The hybrid drill bit of claim 1 , further comprising at least one shim between the at least one rolling cutter assembly and the pocket to change a radial rolling cutter exposure.

9. A method for manufacturing a hybrid drill bit comprising:
forming at least one rolling cutter assembly pocket in a hybrid bit body comprising a first torque-reacting structure;
providing at least one rolling cutter assembly comprising a head onto which a cutter element is rotatably coupled;
providing a second torque-reacting structure on the at least one rolling cutter assembly configured to operatively engage the first torque-reacting structure to resist relative movement between the at least one rolling cutter assembly and the bit body;
forming a plurality of mechanical fastener openings in the at least one rolling cutter assembly;
forming a plurality of mechanical fastener receptacles in the bit body corresponding to the plurality of mechanical fastener openings;
providing a plurality of mechanical fasteners fabricated from high-strength, high-fracture toughness, corrosion-resistant metal alloy configured to securely and removably couple the rolling cutter assemblies to the pockets;
providing a locking structure on a portion of at least one fastener and configured to provide an interference fit between the locking structure and an associated fastener opening;
adjustably positioning the at least one rolling cutter assembly in the pocket to establish a predetermined exposure of the at least one rolling cutter assembly;
tightening the fasteners against the at least one rolling cutter assembly to secure the at least one rolling cutter assembly to the bit body;
placing a locking cap on an exposed portion of each fastener to prevent relative rotation between the fastener and the cap;
welding at least a portion of each locking cap to prevent dislodgement of each locking cap from the respective fastener and to prevent relative rotation between each locking cap and the body; and
joining adjacent locking caps with weldments.

10. The method of claim 9 , wherein the first and second torque-reacting structures comprise a tongue and groove configuration.

11. The method of claim 9 , wherein the fastener openings are substantially round and configured for a location fit with a portion of the mechanical fastener.

12. The method of claim 9 , wherein a portion of at least one mechanical fastener is configured for interference fit with a fastener opening.

13. The method of claim 12 , wherein the interference fit causes deformation of the fastener opening.

14. The method of claim 13 , wherein the deformation in the fastener opening secures the head in an axial location.

15. The method of claim 13 , wherein the deformation in the fastener opening secures the head in an axial location.

16. The method of claim 12 , wherein the deformation is elastic deformation.

17. The method of claim 12 , wherein the deformation is plastic deformation.

18. The method of claim 9 , wherein adjustably positioning the at least one rolling cutter assembly in the pocket comprises placing one or more shims between the at least one rolling cutter assembly and the pocket.

19. A hybrid drill bit comprising:
a rolling cutter assembly pocket formed into a hybrid bit body;
at least one rolling cutter assembly comprising a head onto which a cutter element is rotatably coupled;
the at least one rolling cutter assembly adjustably placed in the pocket in a predetermined position;
the head comprising a plurality of mechanical fastener openings;
a plurality of mechanical fasteners configured to securely and removably couple the at least one rolling cutter assembly to the pocket to establish a predetermined rolling cutter exposure;
a plurality of locking caps, each locking cap being configured to engage an exposed portion of a respective fastener to prevent relative rotation between the fastener and the at least one rolling cutter assembly; and
a plurality of weldments engaging at least a portion of each locking cap, the plurality of weldments configured to prevent dislodgement of each locking cap from the respective fastener and to prevent relative rotation between each locking cap and the body, each weldment of the plurality of weldments being disposed between adjacent locking caps of the plurality of locking caps and joining the adjacent locking caps of the plurality of locking caps.

20. The hybrid drill bit of claim 19 , further comprising a torque-reacting structure disposed between the rolling cutter assembly and the bit body.

21. The hybrid drill bit of claim 20 , wherein the torque-reacting structure comprises a tongue and groove system.

22. The hybrid drill bit of claim 19 , wherein a portion of at least one mechanical fastener is configured for an interference fit with a fastener opening.

23. The hybrid drill bit o

Assignees

• Baker Hughes Inc

Inventors

• Schroder Jon

Classifications

• E21B10/20

  characterised by detachable or adjustable parts, e.g. legs or axles · CPC title

• E21B10/14 Primary

  combined with non-rolling cutters other than of leading-portion type · CPC title

• B23P11/02

  by first expanding and then shrinking or vice versa, e.g. by using pressure fluids; by making force fits · CPC title

• E21B10/62

  characterised by parts, e.g. cutting elements, which are detachable or adjustable (E21B10/64 takes precedence; for roller bits E21B10/20; for augers E21B10/44) · CPC title