# US 2017/0254151 A1 · Semi-sealed rotary drill tool > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0254151 A1 - Document ID: US20170254151A1 - Status: Published application - Kind: A1 - Application number: 15/506,833 - Filed: 2015-08-24 - Published: 2017-09-07 - Earliest claimed: 2014-08-28 - Assignees: Sandvik Intellectual Property AB - Applicants: Sandvik Intellectual Property AB - Inventors: Karl-Oskar FINNMAN - Web page: https://patentgrep.com/patent/US20170254151A1 ## CPC - E21B 10/23: with drilling fluid supply to the bearings - E21B 10/08: Roller bits (E21B10/26 takes precedence; roller core bits E21B10/06; characterised by wear resisting parts E21B10/50) - E21B 10/18: characterised by conduits or nozzles for drilling fluids - E21B 10/22: characterised by bearing, lubrication or sealing details - E21B 10/24: characterised by lubricating details (E21B10/23 takes precedence) - E21B 10/25: characterised by sealing details - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract A rotary drill tool for cutting rock includes at least one journal leg mounting a spindle and a respective rotary cone cutter. The spindle includes a plurality of fluid distribution passageways arrnaged to provide a supply of a cooling and cleaning fluid to the bearing assembly. Vent holes are provided through the cutter to allow an exhaust flow of fluid and an annular seal is provided at a base region of the spindle to maintain a positive fluid pressure within the cutter cavity to prevent dust and dirt ingress. ## Claims ### Claim 1 A rotary drill tool for cutting rock comprising: a main body having an internal fluid supply passageway; a spindle projecting from the main body and having at least one internal fluid distribution passageway in communication with the supply passageway and extending within the spindle to allow a fluid received from the supply passageway to flow through and exit the spindle; a cutter rotatably mounted on the spindle via bearings, the cutter having an external region to cut rock and at least one vent hole to allow the fluid received from the distribution passageway to exit the tool as the cutter is rotated on the spindle; and an annular seal positioned between a base region of the spindle and the cutter to restrict fluid exiting the tool at the base region. ### Claim 2 The tool as claimed in claim h wherein the spindle includes an annular shoulder and an end, the shoulder being positioned axially between the base region and the end, wherein the distribution passageway is divided into at least two distribution passageways, a first distribution passageway exiting the spindle substantially at the shoulder and a second distribution passageway exiting the spindle substantially at the end. ### Claim 3 (depends on 2) The tool as claimed in claim 2, wherein the first passageway is divided into two passageways exiting at different circumferential regions of the shoulder. ### Claim 4 (depends on 2) The tool as claimed in claim 2, wherein the shoulder is defined, in part, by an annular first bearing surface, the first passageway exiting the spindle at the first bearing surface. ### Claim 5 (depends on 4) The tool as claimed in claim 4, wherein at least part of the first bearing surface is aligned substantially perpendicular to a longitudinal axis of the spindle. ### Claim 6 (depends on 5) The tool as claimed in claim 5, wherein the end is defined, in part, by a second surface aligned substantially perpendicular to the axis of the spindle and the second distribution passageway exiting the spindle at the second surface. ### Claim 7 (depends on 2) The tool as claimed in claim 2, wherein the bearings include a first set of roller bearings mounted at or towards the base region; a second set of roller bearings mounted at or towards an end of the spindle; and a set of ball bearings mounted axially between the first and second set of roller bearings, wherein the first passageway exits the spindle axially between the set of ball bearings and the second set of roller bearings. ### Claim 8 (depends on 7) The tool as claimed in claim 7, wherein the cutter has an internal cavity to receive the spindle and the bearings, the cavity being defined axially by a base section arranged to accommodate the first set of roller bearings; an intermediate section arranged to accommodate the set of ball bearings and an end section arranged to accommodate the second set of roller bearings, wherein at least one vent hole extends through the cutter at a position closest to the end section and at least one vent hole extends through the cutter at a position axially between the end and the intermediate section. ### Claim 9 (depends on 8) The tool as claimed in claim 8, wherein at least one vent hole extends through the cutter at a position closest to the base section. ### Claim 10 (depends on 7) The tool as claimed in claim 7, comprising three sets of vent holes, a first set positioned at or towards a base of the cutter, a third set positioned at or towards an apex of the cutter and a second set positioned axially between the first and third sets of vent holes. ### Claim 11 (depends on 10) The tool as claimed in claim 10 wherein the first set includes one to four vent holes and the second and third sets each include two to six vent holes. ### Claim 12 (depends on 11) The tool as claimed in claim 11, wherein the first set includes one vent hole and the second and third sets each include four vent holes. ### Claim 13 (depends on 1) The tool as claimed in claim 1 wherein the cutter includes an annular groove provided at an internal facing surface) to at least partially accommodate the seal. ### Claim 14 (depends on 13) The tool as claimed in claim 13 wherein the spindle includes a cylindrical neck provided at a junction with the main body wherein the seal is positioned radially between the groove and a radially outer surface of the neck. ### Claim 15 (depends on 10) The tool as claimed in claim 10, wherein a combined cross sectional area of the vent holes is substantially equal to or less than a cross sectional area of the supply passageway.