By-pass fluid passageway for drill tool

Patent metadata

Field	Value
Publication number	US-10626677-B2
Application number	US-201515506836-A
Country	US
Kind code	B2
Filing date	Aug 24, 2015
Priority date	Aug 28, 2014
Publication date	Apr 21, 2020
Grant date	Apr 21, 2020

Abstract

A rotary drill tool for cutting rock includes a set of journal legs that rotatably mount rotating cone shaped cutters via respective bearing assemblies. A fluid supply passageway extends through the journal legs to provide a cooling and cleaning fluid to the bearings during use. A by-pass passageway extends through a base region of the spindle that mounts each cone cutter and is provided in direct fluid communication with the supply passageway to divert the fluid to a base region of the bearing assembly.

First claim

The invention claimed is:

1. A rotary drill tool for cutting rock comprising:
a main body having a leg;
a spindle projecting from the leg to mount a rotary cutter via a plurality of bearings, the plurality of bearings including a first set of roller bearings, a second set of roller bearings and a set of ball bearings, wherein the spindle includes a longitudinal axis, a base region, a base raceway extending axially between the base region and a bearing raceway, the bearing raceway having a concave external surface and extending axially between the base region and an annular shoulder and an annular section extending axially between the bearing raceway and an end of the spindle, the annular shoulder being positioned axially between the bearing raceway and the end;
a fluid supply passageway extending through the leg and having a terminal end positioned in communication with a fluid directing passageway extending through the spindle, at least a part of the fluid directing passageway configured to allow at least some of the bearings to be loaded into position between the spindle and the cutter, wherein the cutter includes at least one vent hole positioned at or towards an apex of the cutter and a fluid received from the fluid directing passageway exiting the tool from the at least one vent hole;
a by-pass passageway extending through the base region of the spindle, the by-pass passageway emerging at the base raceway and having a first end in communication with a section of the fluid supply passageway upstream of the terminal end and a second end that emerges from the base region of the spindle to supply fluid to the first set of roller bearings, the base raceway being arranged to mount the first set of roller bearings at or towards the base region of the spindle, the set of ball bearings being positioned at the bearing raceway axially between the first set of roller bearings and the end of the spindle, an end of the fluid directing passageway emerging at the bearing raceway, the second end of the by-pass passageway emerging at the first set of roller bearings, wherein the second set of roller bearings are mounted at the annular section towards the end of the spindle and the set of ball bearings are mounted axially between the first and second set of roller bearings; and
at least one distribution passageway extending within the spindle and provided in communication with the fluid directing passageway, wherein the distribution passageway is divided into at least two passageways, a first passageway exiting the spindle at the shoulder and a second passageway exiting the spindle at the end.

2. The tool as claimed in claim 1 , wherein the by-pass passageway extends transverse or substantially perpendicular to the supply passageway.

3. The tool as claimed in claim 1 , wherein the by-pass passageway is aligned substantially parallel with a longitudinal axis of the spindle.

4. The tool as claimed in claim 1 , wherein the base raceway is defined, in part, by a bearing support surface aligned substantially perpendicular or transverse to the longitudinal axis of the spindle, the by-pass passageway emerging at the bearing support surface.

5. The tool as claimed in claim 4 , wherein an end surface of each of the first set of roller bearings is positioned in contact with the bearing support surface, the by-pass passageway emerging adjacent to the end surfaces of the first set of roller bearings.

6. The tool as claimed in claim 1 , further comprising an annular seal positioned between the base region of the spindle and the cutter to restrict fluid exiting the tool at the base region, the seal defining a semi-sealed internal region of the cutter in which the bearings are located.

7. The tool as claimed in claim 6 , wherein the second end of the by-pass passageway emerges at the internal region.

8. The tool as claimed in claim 1 , wherein a cross-sectional area of the by-pass passageway is substantially equal to or less than a cross-sectional area of each of the first and second distribution passageways.

9. The tool as claimed in claim 1 , wherein the fluid by-pass passageway is a single by-pass passageway extending in communication between the section of the supply passageway and the bearings.

10. The tool as claimed in claim 1 , wherein the fluid by-pass passageway is a plurality of by-pass passageways extending from at least one section of the supply passageway upstream of the terminal end.

11. The tool as claimed in claim 1 , comprising three sets of vent holes, a first set of vent holes being positioned at or towards a base of the cutter, a third set of vent holes being positioned at or towards the apex of the cutter and a second set of vent holes being positioned axially between the first and third sets of vent holes, wherein the by-pass passageway emerges from the spindle at a position axially closer to the base region of the cutter relative to a position at which the first set of vent holes extend through the cutter.

Assignees

• Sandvik Intellectual Property

Inventors

• Finnman Karl-Oskar

Classifications

• E21B10/24

  characterised by lubricating details (E21B10/23 takes precedence) · CPC title

• E21B10/16

  characterised by tooth form or arrangement · CPC title

• E21B10/25

  characterised by sealing details · CPC title

• E21B10/23 Primary

  with drilling fluid supply to the bearings · CPC title

• E21B10/18 Primary

  characterised by conduits or nozzles for drilling fluids · CPC title