Matrix fixed cutter drill bits and methods for manufacturing same

Patent metadata

Field	Value
Publication number	US-9631435-B2
Application number	US-201314101795-A
Country	US
Kind code	B2
Filing date	Dec 10, 2013
Priority date	Dec 10, 2013
Publication date	Apr 25, 2017
Grant date	Apr 25, 2017

Abstract

A fixed cutter drill bit for drilling a borehole in earthen formations includes a blank assembly and a matrix crown fixably mounted to the blank assembly. The blank assembly includes an annular mandrel and a plurality of elongate studs fixably coupled to the mandrel. The mandrel has a first end distal the crown and a second end engaging the crown. In addition, the mandrel includes a plurality of bores extending axially from the second end. Each elongate stud has a first end disposed within one of the bores and a second end disposed in the crown distal the mandrel.

First claim

What is claimed is:

1. A fixed cutter drill bit for drilling a borehole in earthen formations, the bit having a central axis and a cutting direction of rotation, the bit comprising:
a blank assembly including an annular mandrel and a plurality of elongate studs fixably coupled to the mandrel;
a matrix crown fixably mounted to the blank assembly;
wherein the mandrel is coaxially aligned with the central axis and has a first end distal the crown and a second end engaging the crown;
wherein the mandrel includes a plurality of bores extending axially from the second end;
wherein each elongate stud has a first end disposed within one of the bores and a second end disposed in the crown distal the mandrel; and
wherein at least one elongate stud has a different length than the other elongate studs of the plurality of elongate studs.

2. The fixed cutter drill bit of claim 1 , wherein the plurality of bores is arranged in a row and circumferentially spaced.

3. The fixed cutter drill bit of claim 2 , wherein the plurality of elongate studs is arranged in more than one row.

4. The fixed cutter drill bit of claim 1 , wherein each bore of the plurality of bores is oriented parallel to the other bores of the plurality of bores.

5. A blank assembly for a fixed cutter drill bit, the blank assembly comprising:
an annular mandrel having a central axis, a first end, and a second end axially opposite the first end, wherein the mandrel includes a plurality of parallel bores extending axially from the second end; and
a plurality of elongate studs fixably secured to the mandrel, wherein each stud has a first end seated in one of the bores and a second end distal the mandrel;
wherein the plurality of elongate studs is arranged in more than one row.

6. The blank assembly of claim 5 , wherein the plurality of bores is arranged in a row and circumferentially spaced.

7. The blank assembly of claim 5 , wherein each bore of the plurality of bores is oriented parallel to the other bores of the plurality of bores.

8. The blank assembly of claim 5 , wherein at least one elongate stud has a different length than the other elongate studs of the plurality of elongate studs.

Assignees

• Nat Oilwell Dht Lp

Inventors

• Garner Michael
• Marshall Jan Edgar
• Sreshta Harold A

Classifications

• E21B10/42 Primary

  Rotary drag type drill bits with teeth, blades or like cutting elements, e.g. fork-type bits, fish tail bits (characterised by wear resisting parts E21B10/46; by conduits or nozzles for drilling fluid E21B10/60; by detachable or adjustable parts E21B10/62) · CPC title

• E21B10/54

  the bit being of the rotary drag type, e.g. fork-type bits · CPC title

• E21B10/43 Primary

  characterised by the arrangement of teeth or other cutting elements · CPC title