US20130307317A1 - Cutting Bit With Split Wear Ring - Google Patents
Cutting Bit With Split Wear Ring Download PDFInfo
- Publication number
- US20130307317A1 US20130307317A1 US13/474,663 US201213474663A US2013307317A1 US 20130307317 A1 US20130307317 A1 US 20130307317A1 US 201213474663 A US201213474663 A US 201213474663A US 2013307317 A1 US2013307317 A1 US 2013307317A1
- Authority
- US
- United States
- Prior art keywords
- wear ring
- angled
- split wear
- angle
- annular channel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
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Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21C—MINING OR QUARRYING
- E21C35/00—Details of, or accessories for, machines for slitting or completely freeing the mineral from the seam, not provided for in groups E21C25/00 - E21C33/00, E21C37/00 or E21C39/00
- E21C35/18—Mining picks; Holders therefor
- E21C35/183—Mining picks; Holders therefor with inserts or layers of wear-resisting material
Landscapes
- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Mechanical Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Earth Drilling (AREA)
- Milling Processes (AREA)
Abstract
A cutting bit includes an elongate body having a shank portion and a head portion with a forward end. The head portion has an annular channel defined therein adjacent to and rearwardly of the forward end of the head portion. The annular channel has an angled bottom surface. The cutting bit also includes a split wear ring positionable in the annular channel and structured and arranged to be retainably held in the annular channel. The cutting bit further includes a hard cutting tip affixed to the forward end of the head portion.
Description
- The present invention relates to road milling, mining and excavating tools, and more particularly relates to cutting bits with wear rings that reduce wear of such tools.
- Cutting bits are used in various road milling, mining and excavating operations. The bits are mounted on a support structure such as a rotary drum. Each bit typically has a hard wear resistant tip made of a material such as tungsten carbide attached to a generally conical steel head of the bit. A problem with such designs is that the softer steel backing material erodes during cutting operations.
- Wear resistant cutting bits have been developed in order to increase erosion resistance. For example, U.S. Pat. No. 7,530,642 discloses the use of wear rings positioned in an annular channel formed in a cutting bit body. However, it has been found that these wear rings are difficult to assemble and retain in place during the manufacturing process, e.g. while brazing the wear rings in the channel in the cutting bit body. In addition, a steel retainer ring is needed to hold the wear rings in place during the manufacturing process.
- Thus, it can be appreciated that it would be highly desirable to provide an improved cutting bit with improved wear resistance. It can also be appreciated that it would be highly desirable to provide such an improved cutting bit that is easier and more affordable to manufacture.
- In accordance with an aspect of the invention, a cutting bit includes an elongate body having a shank portion and a head portion with a forward end, wherein the head portion has an annular channel defined therein adjacent to and rearwardly of the forward end of the head portion. The annular channel has an angled bottom surface. The cutting bit also includes a split wear ring positionable in the annular channel and structured and arranged to be retainably held in the annular channel, and a hard cutting tip affixed to the forward end of the head portion.
- In accordance with another aspect of the invention, a split wear ring for positioning in an annular groove formed on a head portion of a cutting bit having a central longitudinal axis includes an angled lower surface and an opposing angled upper surface. The angled lower surface and the opposing angled upper surface are structured and arranged to be retainably held in the annular channel.
- In accordance with an additional aspect of the invention, an elongate body of a cutting bit adapted to receive a split wear ring includes a shank portion and a head portion with a forward end. The head portion has an annular channel defined therein adjacent to and rearwardly of the forward end of the head portion. The annular channel is structured and arranged to retainably hold the split wear ring therein.
- These and other aspects of the present invention will be more fully understood following a review of this specification and drawings.
-
FIG. 1 is an isometric view of a cutting bit, in accordance with an aspect of the invention. -
FIG. 2 is a partial sectional view of the cutting bit shown inFIG. 1 , in accordance with an aspect of the invention. -
FIG. 3 is an additional partial sectional view similar toFIG. 2 with parts removed, in accordance with an aspect of the invention. -
FIG. 4 is an isometric view of a split wear ring, in accordance with an aspect of the invention. -
FIG. 5 is an isometric view of a section of the split wear ring shown inFIG. 4 , in accordance with an aspect of the invention. -
FIG. 6 is a partial, front sectional view of the section of the split wear ring shown inFIG. 5 , in accordance with an aspect of the invention. - Referring to
FIGS. 1-3 , there is illustrated a cutting bit, generally designated asreference number 10, in accordance with aspects of the invention. It will be appreciated that the invention has application to various kinds of cutting tools useful in various kinds of cutting operations. Exemplary operations include, without limitation, road planing (or milling), coal mining, concrete cutting, and other kinds of cutting operations wherein a cutting bit with a hard cutting member impinges against a substrate (e.g., earth strata, pavement, asphaltic highway material, concrete, and the like) breaking the substrate into pieces of a variety of sizes including larger-size pieces or chunks and smaller-sized pieces including dust-like particles. In addition, it will be appreciated that thecutting bit 10 of the invention may be manufactured in various sizes and dimensions depending upon the desired application of the tool. -
Cutting bit 10 has a central longitudinal axis X-X.Cutting bit 10 includes an elongate body, generally designated as 12, which typically is made of, for example, steel.Elongate body 12 has an axialforward end 14 and an axialrearward end 16. -
Elongate body 12 further includes ahead portion 18 adjacent the axialforward end 14 and ashank portion 20 adjacent the axialrearward end 16. Theshank portion 20 may be provided with various shapes and configurations. In one aspect, theshank portion 20 may be structured and arranged to be non-rotatable such that thecutting bit 10 is a non-rotatable type cutting tool. In another aspect, theshank portion 20 may be structured and arranged to be rotatable such that thecutting bit 10 is a rotatable type cutting tool. - In accordance with another aspect of the invention, the
cutting bit 10 further includes a hard cutting tip, generally designated asreference number 22 adjacent the axial forward end 14 (see, for example,FIGS. 2 and 3 ). Thehard cutting tip 22 may be affixed by, for example, brazing thehard cutting tip 22 to, for example,socket 24 formed in thehead portion 18 adjacent the axialforward end 14 of thebody 12. - In one aspect, the
hard cutting tip 22 is structured and arranged so as to include a substrate 26 (see, for example,FIG. 2 ) which may be made from, for example, a hard material such as, for example, cemented (cobalt) tungsten carbide. Thehard cutting tip 22 may further include a layer of asuperhard material 28 adhered to the substrate 26 (see, for example,FIGS. 1 and 2 ). The layer ofsuperhard material 28 may include, for example, polycrystalline diamond (PCD) or polycrystalline cubic boron nitride (PCBN). - The layer of
superhard material 28 may have a generally constant thickness and can be applied to thesubstrate 26 by any one of the number of known techniques wherein thesuperhard material 28 is, for example, bonded to the surface of thesubstrate 26. For example, one can apply the layer ofsuperhard material 28, e.g. PCD, to thesubstrate 26 by any one of a number of techniques wherein the layer ofsuperhard material 28 is bonded to the surface of thesubstrate 26. The following patent documents disclose exemplary compositions of polycrystalline diamond as well as exemplary techniques to apply a layer of polycrystalline diamond to the surface of a substrate: U.S. Pat. No. 4,063,909 to Mitchell, U.S. Pat. No. 4,604,106 to Hall et al., U.S. Pat. No. 4,694,918 to Hall, and U.S. Pat. No. 4,811,801 to Salesky et al. - In addition, the
head portion 18 defines anannular channel 30. Theannular channel 30 is adjacent to and rearwardly of the axialforward end 14 of thehead portion 18. In one aspect, theannular channel 30 extends at least partially circumferentially about anouter surface 32 of thehead portion 18. In another aspect, theannular channel 30 extends circumferentially about thehead portion 18 so as to form a continuous groove or channel. - The
annular channel 30 includes a sloped orangled bottom surface 34, anangled top surface 36 generally opposed to theangled bottom surface 34, and aside wall 38 extending between theangled bottom surface 34 and theangled top surface 36. Theside wall 38 may be sloped, angled or parallel with respect to the central longitudinal axis X-X of thecutting bit 10. - In an aspect of the invention, the
angled bottom surface 34 is generally planar. In another aspect, theangled bottom surface 34 extends in a plane at an angle A (see, for example,FIG. 3 ) with respect to the central longitudinal axis X-X of thecutting bit 10. In one aspect, angle A is less than 90 degrees. In another aspect, angle A is in the range of about 60 degrees to about 70 degrees. - In an aspect of the invention, the angled
top surface 36 is generally planar. In another aspect, the angledtop surface 36 extends in a plane at an angle B (see, for example,FIG. 2 ) with respect to the central longitudinal axis X-X of the cuttingbit 10. In one aspect, angle B is less than 90 degrees. In another aspect, angle B is in the range of about 60 degrees to about 70 degrees. - Referring to
FIGS. 1 , 2 and 4-6, the cuttingbit 10 further includes a split wear ring, generally designated asreference number 40. Thesplit wear ring 40 is positionable in theannular channel 30. The hardness, size and location of thesplit wear ring 40 are selected in order to significantly reduce erosion and wear of the relativelysoft body 12 of the cuttingbit 10. Thesplit wear ring 40 may be made of any suitable hard material such as carbides, aluminum oxide, hard ceramic materials, hardened tool steels and the like. For example, thesplit wear ring 40 may be made of tungsten carbide. In one example, thesplit wear ring 40 and cuttingtip 22 are made of the same hard material. Furthermore, portions of thesplit wear ring 40 may be made of different materials, e.g., materials having different hardness and/or toughness properties, graded materials, and the like. - In one aspect of the invention, the
split wear ring 40 comprises two or more split wearring sections 40 a that are arranged to make thesplit wear ring 40. For example,FIG. 4 illustrates two splitwear ring sections 40 a arranged end to end to form thesplit wear ring 40. However, it will be appreciated that any other suitable number of split wear ring sections may be used, such as three sections, four sections, etc. In one aspect, the splitwear ring sections 40 a may haveflat faces 42 which abut each other when assembled in theannular channel 30. - As described, the
split wear ring 40 is positionable in theannular channel 30. In accordance with an important aspect of the invention, thesplit wear ring 40 is structured and arranged to be retainably held in theannular channel 30 when positioned therein. As used herein, the terms “retainably held” or “retainably hold” generally refer to the structure of thesplit wear ring 40 being such that it cooperates with the structure of theannular channel 30 so as to retain and hold thesplit wear ring 40, i.e. the splitwear ring sections 40 a, within theannular channel 30 during assembly of the cuttingbit 10 without the need for any additional means for holding thesplit wear ring 40 in position, such as a retainer ring, during assembly. During assembly of the cuttingbit 10, the splitwear ring sections 40 a are first positioned in theannular channel 30. Then, the splitwear ring sections 40 a go through a process to permanently secure or affix thesplit wear ring 40 to thehead portion 18 and, more particularly, to permanently secure or affix thesplit wear ring 40 within theannular channel 30. This process may be, for example, a brazing process during which it is important that the splitwear ring sections 40 a are securely retainably held in place so as to be properly positioned within theannular channel 30. In one example, the cuttingbit 10 may be maintained in a generally upright vertical position, such as the orientation shown inFIG. 2 , during the brazing process or alternatively the cuttingbit 10 may be maintained in a generally downward vertical position, such as turned 180 degrees from the orientation shown inFIG. 2 , during the brazing process. Advantageously, the novel structure and arrangement of theannular channel 30 and thesplit wear ring 40 of the invention and the cooperation of these components allow for the correct, efficient and economical assembly of the cuttingbit 10. - In one aspect, the
split wear ring 40 includes an angledlower surface 44 that is positioned adjacent to theangled bottom surface 34 of theannular channel 30. The angledlower surface 44 effectively cooperates with theangled bottom surface 34 of theannular channel 30 so as to retainably hold thesplit wear ring 40 in theannular channel 30 during assembly. - In another aspect, the
split wear ring 40 also includes an angledupper surface 46 that is positioned adjacent to the angledtop surface 36 of theannular channel 30. The angledupper surface 46 effectively cooperates with the angledtop surface 36 of theannular channel 30 so as to further retainably hold thesplit wear ring 40 in theannular channel 30 during assembly. - Thus, it will be appreciated that the angled
lower surface 44 and the angledupper surface 46 of thesplit wear ring 40 are structured and arranged to advantageously cooperate with and be retainably held in theannular channel 30. In addition, it will be appreciated that theangled bottom surface 34 and the angledtop surface 36 of theannular channel 30 are structured and arranged to advantageously cooperate with and retainably hold thesplit wear ring 40 therein. - In an aspect of the invention, the angled
lower surface 44 of thesplit wear ring 40 is generally planar. In another aspect, the angledlower surface 44 extends in a plane at an angle C to a center axis X1-X1 of thesplit wear ring 40 that is perpendicular to a longitudinal axis L-L of the split wear ring 40 (see, for example,FIG. 6 ). In one aspect, angle C is less than 90 degrees. In another aspect, angle C is in the range of about 60 degrees to about 70 degrees. Thus, it will be appreciated that in one aspect the angledlower surface 44 of thesplit wear ring 40 may have the same angle or may have a different angle as theangled bottom surface 34 of theannular channel 30. - In an aspect of the invention, the angled
upper surface 46 of thesplit wear ring 40 is generally planar. In another aspect, the angledupper surface 46 extends in a plane at an angle D to a center axis X1-X1 of thesplit wear ring 40 that is perpendicular to a longitudinal axis L-L of the split wear ring 40 (see, for example,FIG. 6 ). In one aspect, angle D is less than 90 degrees. In another aspect, angle D is in the range of about 60 degrees to about 70 degrees. Thus, it will be appreciated that in one aspect the angledupper surface 46 of thesplit wear ring 40 may have the same angle or may have a different angle as the angledtop surface 36 of theannular channel 30. - Whereas particular aspects of this invention have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details of the present invention may be made without departing from the invention as defined in the appended claims.
Claims (20)
1. A cutting bit comprising:
an elongate body having a shank portion and a head portion with a forward end, wherein the head portion has an annular channel defined therein adjacent to and rearwardly of the forward end of the head portion, the annular channel having an angled bottom surface;
a split wear ring positionable in the annular channel and structured and arranged to be retainably held in the annular channel; and
a hard cutting tip affixed to the forward end of the head portion.
2. The cutting bit of claim 1 , wherein the split wear ring has an angled lower surface positioned adjacent to and for cooperating with the angled bottom surface of the annular channel to retainably hold the split wear ring in the annular channel.
3. The cutting bit of claim 2 , wherein the annular channel includes an angled top surface generally opposed to the angled bottom surface and a side wall extending between the angled bottom surface and the angled top surface.
4. The cutting bit of claim 3 , wherein the split wear ring has an angled upper surface positioned adjacent to and for cooperating with the angled top surface of the annular channel to retainably hold the split wear ring in the annular channel.
5. The cutting bit of claim 1 , wherein the angled bottom surface is generally planar and extends in a plane at an angle A to a central longitudinal axis of the elongate body, wherein the angle A is less than 90 degrees.
6. The cutting bit of claim 5 , wherein the angle A is in the range of 60 degrees to 70 degrees.
7. The cutting bit of claim 3 , wherein the angled top surface is generally planar and extends in a plane at an angle B to a central longitudinal axis of the elongate body, wherein the angle B is less than 90 degrees.
8. The cutting bit of claim 7 , wherein the angle B is in the range of 60 degrees to 70 degrees.
9. The cutting bit of claim 4 , wherein:
the angled lower surface is generally planar and extends in a plane at an angle C to a center axis of the split wear ring that is perpendicular to a longitudinal axis containing the split wear ring, wherein the angle C is less than 90 degrees; and
the angled upper surface is generally planar and extends in a plane at an angle D to a center axis of the split wear ring that is perpendicular to a longitudinal axis containing the split wear ring, wherein the angle D is less than 90 degrees.
10. The cutting bit of claim 1 , wherein the split wear ring includes two sections.
11. The cutting bit of claim 1 , wherein the split wear ring includes adjacent sections that contact each other at abutting faces.
12. A split wear ring for positioning in an annular channel formed on a head portion of a cutting bit having a central longitudinal axis, the split wear ring comprising:
an angled lower surface; and
an opposing angled upper surface, wherein the angled lower surface and the opposing angled upper surface are structured and arranged to be retainably held in the annular channel.
13. The split wear ring of claim 12 , wherein the angled lower surface is generally planar and extends in a plane at an angle C to a center axis of the split wear ring that is perpendicular to a longitudinal axis containing the split wear ring, wherein the angle C is less than 90 degrees.
14. The split wear ring of claim 12 , wherein the angled upper surface is generally planar and extends in a plane at an angle D to a center axis of the split wear ring that is perpendicular to a longitudinal axis containing the split wear ring, wherein the angle D is less than 90 degrees.
15. The split wear ring of claim 12 , wherein the split wear ring includes two sections.
16. The split wear ring of claim 12 , wherein the split wear ring includes adjacent sections that contact each other at abutting faces.
17. An elongate body of a cutting bit adapted to receive a split wear ring, the elongate body comprising:
a shank portion; and
a head portion with a forward end, wherein the head portion has an annular channel defined therein adjacent to and rearwardly of the forward end of the head portion, the annular channel structured and arranged to retainably hold the split wear ring therein.
18. The elongate body of claim 17 , wherein the annular channel includes an angled bottom surface, an angled top surface generally opposed to the angled bottom surface and a side wall extending between the angled bottom surface and the angled top surface.
19. The elongate body of claim 18 , wherein the angled bottom surface is generally planar and extends in a plane at an angle A to a central longitudinal axis of the elongate body, wherein the angle A is less than 90 degrees.
20. The elongate body of claim 18 , wherein the angled bottom surface is generally planar and extends in a plane at an angle B to a central longitudinal axis of the elongate body, wherein the angle B is less than 90 degrees.
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/474,663 US20130307317A1 (en) | 2012-05-17 | 2012-05-17 | Cutting Bit With Split Wear Ring |
CN2013101756929A CN103422418A (en) | 2012-05-17 | 2013-05-14 | Cutting bit |
DE102013105001A DE102013105001A1 (en) | 2012-05-17 | 2013-05-15 | Body of a cutting head, wear ring and cutting head with split wear ring |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/474,663 US20130307317A1 (en) | 2012-05-17 | 2012-05-17 | Cutting Bit With Split Wear Ring |
Publications (1)
Publication Number | Publication Date |
---|---|
US20130307317A1 true US20130307317A1 (en) | 2013-11-21 |
Family
ID=49511080
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/474,663 Abandoned US20130307317A1 (en) | 2012-05-17 | 2012-05-17 | Cutting Bit With Split Wear Ring |
Country Status (3)
Country | Link |
---|---|
US (1) | US20130307317A1 (en) |
CN (1) | CN103422418A (en) |
DE (1) | DE102013105001A1 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20170254201A1 (en) * | 2014-10-17 | 2017-09-07 | Vermeer Manufacturing Company | Protective wear sleeve for cutting element |
US11524303B2 (en) * | 2015-11-06 | 2022-12-13 | Betek Gmbh & Co. Kg | Tool system |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20190263014A1 (en) * | 2018-02-27 | 2019-08-29 | Jtekt Corporation | Cutting method and cutting tool |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20030141753A1 (en) * | 2002-01-30 | 2003-07-31 | Kent Peay | Rotary cutting bit with material-deflecting ledge |
US7530642B2 (en) * | 2006-12-15 | 2009-05-12 | Kennametal Inc. | Cutting bit with split wear ring and method of making same |
US7568770B2 (en) * | 2006-06-16 | 2009-08-04 | Hall David R | Superhard composite material bonded to a steel body |
US7963616B2 (en) * | 2006-12-20 | 2011-06-21 | Sandvik Intellectual Property Ab | Rotary cutting pick |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
IE42084B1 (en) | 1974-09-18 | 1980-06-04 | De Beers Ind Diamond | Abrasive bodies |
US4525178A (en) | 1984-04-16 | 1985-06-25 | Megadiamond Industries, Inc. | Composite polycrystalline diamond |
US4694918A (en) | 1985-04-29 | 1987-09-22 | Smith International, Inc. | Rock bit with diamond tip inserts |
US4811801A (en) | 1988-03-16 | 1989-03-14 | Smith International, Inc. | Rock bits and inserts therefor |
-
2012
- 2012-05-17 US US13/474,663 patent/US20130307317A1/en not_active Abandoned
-
2013
- 2013-05-14 CN CN2013101756929A patent/CN103422418A/en active Pending
- 2013-05-15 DE DE102013105001A patent/DE102013105001A1/en not_active Withdrawn
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20030141753A1 (en) * | 2002-01-30 | 2003-07-31 | Kent Peay | Rotary cutting bit with material-deflecting ledge |
US6709065B2 (en) * | 2002-01-30 | 2004-03-23 | Sandvik Ab | Rotary cutting bit with material-deflecting ledge |
US7568770B2 (en) * | 2006-06-16 | 2009-08-04 | Hall David R | Superhard composite material bonded to a steel body |
US7530642B2 (en) * | 2006-12-15 | 2009-05-12 | Kennametal Inc. | Cutting bit with split wear ring and method of making same |
US7963616B2 (en) * | 2006-12-20 | 2011-06-21 | Sandvik Intellectual Property Ab | Rotary cutting pick |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20170254201A1 (en) * | 2014-10-17 | 2017-09-07 | Vermeer Manufacturing Company | Protective wear sleeve for cutting element |
US11524303B2 (en) * | 2015-11-06 | 2022-12-13 | Betek Gmbh & Co. Kg | Tool system |
Also Published As
Publication number | Publication date |
---|---|
CN103422418A (en) | 2013-12-04 |
DE102013105001A1 (en) | 2013-11-21 |
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Legal Events
Date | Code | Title | Description |
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AS | Assignment |
Owner name: KENNAMETAL INC., PENNSYLVANIA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:BOOKHAMER, PAUL A.;PAROS, NICHOLAS J.;SIGNING DATES FROM 20120507 TO 20120516;REEL/FRAME:028229/0893 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |