Low collision damage bit

Patent metadata

Field	Value
Publication number	US-2016145945-A1
Application number	US-201514944265-A
Country	US
Kind code	A1
Filing date	Nov 18, 2015
Priority date	Nov 25, 2014
Publication date	May 26, 2016
Grant date	—

Abstract

A low collision damage bit may include one or more roller cones including a first material and a second material. The bit may have a bit axis and a bit body, and the second material of the one or more roller cones may be positioned farther from the bit axis than the bit body. The second material may have a hardness or yield strength less than the first material.

First claim

We claim:

1 . A cone for use in a roller cone bit, the cone comprising:
a nose; a heel located at an opposite end from the nose; a hard portion having a first yield strength, the hard portion forming at least a part of the nose; and a soft portion having a second yield strength less than the first yield strength, the soft portion forming at least a portion of the heel.

2 . The cone of claim 1 , the soft portion having one or more teeth.

3 . The cone of claim 1 , the soft portion being welded to the hard portion.

4 . The cone of claim 1 , the hard portion having one or more recesses configured to receive a cutting insert.

5 . The cone of claim 1 , the soft portion being an aluminum alloy.

6 . The cone of claim 1 , the soft portion being an aluminum bronze alloy.

7 . The cone of claim 1 , the soft portion including a gage row of cutting teeth.

8 . The cone of claim 1 further comprising a gage row of cutting teeth, at least one cutting tooth of the gage row including part of the soft portion and part of the hard portion.

9 . A bit for removal of earth, the bit comprising:
a bit body having a bit axis; a leg extending from the bit body; and a cone, the cone being rotatably connected to the leg, the cone having a nose and a heel, at least part of the nose being made of a first material and at least part of the heel being made of a second material, wherein the first material has a greater yield strength than the second material.

10 . The bit of claim 9 , the bit body having a first diameter and the cone at least partially defining a second diameter greater than the first diameter.

11 . The bit of claim 9 , the heel being further from the bit axis than an outer surface of the leg.

12 . The bit of claim 9 , the second material having a yield strength less than 30 ksi.

13 . The bit of claim 9 , the second material having a yield strength less than 35 ksi.

14 . The bit of claim 9 , the cone being rotatably connected to the leg about a cone axis that forms a first angle relative to the bit axis and the heel having a beveled surface that forms a second angle relative to the cone axis.

15 . The bit of claim 14 , the first angle and the second angle being equal.

16 . The bit of claim 14 , the beveled surface being curved in longitudinal cross-section.

17 . The bit of claim 14 , the beveled surface being flat in longitudinal cross-section.

18 . The bit of claim 9 , the cone having a first row of cutting teeth and a second row of cutting teeth, the second row of cutting teeth being proximate the heel, wherein the first row of cutting teeth having a more aggressive profile than the second row of cutting teeth.

19 . The bit of claim 9 , the cone having a first row of cutting teeth and a second row of cutting teeth, the second row of cutting teeth being proximate the heel, wherein the second row of cutting teeth having an IADC 21X rating and the first row of cutting teeth having an IADC 11X rating.

20 . A method of manufacturing a bit, the method comprising:
providing a cone body having a nose and a heel, the cone body being made of a first material having a first hardness; and affixing to the heel a second material having a second hardness, the second hardness being less than the first hardness.

Assignees

• Smith International

Inventors

• Portwood Gary R
• Roth Cary A
• Tedeschi Luca

Classifications

• E21B10/08 Primary

  Roller bits (E21B10/26 takes precedence; roller core bits E21B10/06; characterised by wear resisting parts E21B10/50) · CPC title

• E21B10/50

  the bit being of roller type · CPC title