SE539941C2 - Cutting tool for coal mining, mechanical processing of rocks, use during rotary drilling or working asphalt, concrete or like material, provided with longitudinally extending grooves - Google Patents
Cutting tool for coal mining, mechanical processing of rocks, use during rotary drilling or working asphalt, concrete or like material, provided with longitudinally extending grooves Download PDFInfo
- Publication number
- SE539941C2 SE539941C2 SE1650213A SE1650213A SE539941C2 SE 539941 C2 SE539941 C2 SE 539941C2 SE 1650213 A SE1650213 A SE 1650213A SE 1650213 A SE1650213 A SE 1650213A SE 539941 C2 SE539941 C2 SE 539941C2
- Authority
- SE
- Sweden
- Prior art keywords
- tip
- cutting tool
- base
- grooves
- recess
- Prior art date
Links
- 238000005520 cutting process Methods 0.000 title claims abstract description 135
- 239000000463 material Substances 0.000 title claims description 42
- 239000010426 asphalt Substances 0.000 title claims description 9
- 239000003245 coal Substances 0.000 title claims description 7
- 238000012545 processing Methods 0.000 title claims description 7
- 238000005065 mining Methods 0.000 title claims description 6
- 238000005553 drilling Methods 0.000 title claims description 5
- 239000011435 rock Substances 0.000 title claims description 4
- 229910000851 Alloy steel Inorganic materials 0.000 claims description 11
- 229910001315 Tool steel Inorganic materials 0.000 claims description 5
- 238000003801 milling Methods 0.000 description 17
- 238000012360 testing method Methods 0.000 description 10
- 239000002344 surface layer Substances 0.000 description 7
- 238000001816 cooling Methods 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 6
- 239000000446 fuel Substances 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 3
- 238000005219 brazing Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 229910000679 solder Inorganic materials 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 230000000295 complement effect Effects 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 229910003460 diamond Inorganic materials 0.000 description 2
- 239000010432 diamond Substances 0.000 description 2
- 238000005265 energy consumption Methods 0.000 description 2
- 229920001296 polysiloxane Polymers 0.000 description 2
- 229910052582 BN Inorganic materials 0.000 description 1
- PZNSFCLAULLKQX-UHFFFAOYSA-N Boron nitride Chemical compound N#B PZNSFCLAULLKQX-UHFFFAOYSA-N 0.000 description 1
- 238000007550 Rockwell hardness test Methods 0.000 description 1
- 238000007545 Vickers hardness test Methods 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000011195 cermet Substances 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 239000000498 cooling water Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910001092 metal group alloy Inorganic materials 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 238000004154 testing of material Methods 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK 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
- E21C35/1837—Mining picks; Holders therefor with inserts or layers of wear-resisting material characterised by the shape
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28D—WORKING STONE OR STONE-LIKE MATERIALS
- B28D1/00—Working stone or stone-like materials, e.g. brick, concrete or glass, not provided for elsewhere; Machines, devices, tools therefor
- B28D1/18—Working stone or stone-like materials, e.g. brick, concrete or glass, not provided for elsewhere; Machines, devices, tools therefor by milling, e.g. channelling by means of milling tools
-
- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
- E01C23/00—Auxiliary devices or arrangements for constructing, repairing, reconditioning, or taking-up road or like surfaces
- E01C23/06—Devices or arrangements for working the finished surface; Devices for repairing or reconditioning the surface of damaged paving; Recycling in place or on the road
- E01C23/12—Devices or arrangements for working the finished surface; Devices for repairing or reconditioning the surface of damaged paving; Recycling in place or on the road for taking-up, tearing-up, or full-depth breaking-up paving, e.g. sett extractor
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B10/00—Drill bits
- E21B10/62—Drill bits characterised by parts, e.g. cutting elements, which are detachable or adjustable
- E21B10/627—Drill bits characterised by parts, e.g. cutting elements, which are detachable or adjustable with plural detachable cutting elements
- E21B10/633—Drill bits characterised by parts, e.g. cutting elements, which are detachable or adjustable with plural detachable cutting elements independently detachable
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK 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
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK 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
- E21C35/1831—Fixing methods or devices
-
- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
- E01C23/00—Auxiliary devices or arrangements for constructing, repairing, reconditioning, or taking-up road or like surfaces
- E01C23/06—Devices or arrangements for working the finished surface; Devices for repairing or reconditioning the surface of damaged paving; Recycling in place or on the road
- E01C23/08—Devices or arrangements for working the finished surface; Devices for repairing or reconditioning the surface of damaged paving; Recycling in place or on the road for roughening or patterning; for removing the surface down to a predetermined depth high spots or material bonded to the surface, e.g. markings; for maintaining earth roads, clay courts or like surfaces by means of surface working tools, e.g. scarifiers, levelling blades
- E01C23/085—Devices or arrangements for working the finished surface; Devices for repairing or reconditioning the surface of damaged paving; Recycling in place or on the road for roughening or patterning; for removing the surface down to a predetermined depth high spots or material bonded to the surface, e.g. markings; for maintaining earth roads, clay courts or like surfaces by means of surface working tools, e.g. scarifiers, levelling blades using power-driven tools, e.g. vibratory tools
- E01C23/088—Rotary tools, e.g. milling drums
Landscapes
- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Mechanical Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Civil Engineering (AREA)
- Architecture (AREA)
- Structural Engineering (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- Milling Processes (AREA)
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
Claims (5)
1. Ett skärverktyg (10) för kolbrytning, mekanisk bearbetning av sten, användning vidrotationsborrning eller bearbetning av asfalt, betong eller liknande material,innefattande en spets (20), en kropp (30) och ett skaft (50) för att fästa skärverktyget(10) till en verktygshållare, - varvid kroppen (30) har en yttre kroppsyta (31), en kroppskaftsände (32)anordnad mot skaftet (59) och en kroppspetsände (33) anordnad mot spetsen(20), - varvid spetsen (20) har en yttre spetsyta (21 ), en spetstopp (22) och en spetsbas(23), där spetsbasen (23) är förbunden med kroppens (30) kroppspetsände (33), kännetecknat av att skärverktyget (10) innefattar ett flertal spår (40) som sträcker sig väsentligen kontinuerligt över både den yttre spetsytan (21) och den yttre kroppsytan (31 ), där varje spår har en förutbestämd utsträckning i en hos skärverktyget (10) longitudinell riktning. _ Skärverktyget (10) enligt kravet 1, varvid spetsbasen (23) har en spetsbaslängd (24) i den longitudinella riktningen, och där ett spetsspårsavsnitt (41) hos spåren (40)sträcker sig längs den yttre spetsytan (21) över en större del av spetsbaslängden(21). _ Skärverktyget (10) enligt kravet 1 eller 2, varvid kroppen (30) har en kroppslängd (34) i den longitudinella riktningen, och där ett kroppsspårsavsnitt (42) hos spåren(40) sträcker sig längs den yttre kroppsytan (31) över en större del av kroppslängden(34). _ Skärverktyget (10) enligt något av de tidigare kraven, varvid spetsen (20) innefattar en väsentligen cylindriskt formad del (26) vilken sträcker sig i den longitudinellariktningen mellan spetstoppen (22) och spetsbasen (23), och att en längd (27) hosden väsentligen cylindriskt formade delen (26) överstiger 10 mm. _ Skärverktyget (10) enligt något av de tidigare kraven, varvid kroppen (30) har en radie (38) vilken ökar kontinuerligt längs en jämn kurva från kroppspetsänden (33) tillkroppskaftsänden (32). _ Skärverktyget (10) enligt krav 4 eller krav 5 när detta är underordnat krav 4, varvid spetsen (20) har en radie (28) som ökar kontinuerligt längs en jämn kurva från dencylindriskt formade delen (26) till ett distalt avsnitt av spetsbasen (23). _ Skärverktyget (10) enligt något av de tidigare kraven, varvid ett djup hos spetsspåravsnitten (41) är åtminstone 0,5 mm. PS54881SE00 8. 10. 11 12 13. 14. 15. Skärverktyget (10) enligt något av de tidigare kraven, varvid ett djup (48) hoskroppsspårsavsnitten (42) är åtminstone 1 mm. Skärverktyget (10) enligt något av de tidigare kraven, varvid kroppspetsänden (33)innefattar en fördjupning (60) för att hålla kvar åtminstone en del av spetsen (20) inutifördjupningen (60). Skärverktyget (10) enligt kravet 9, varvid fördjupningen (60) innefattar en sidoväggmed åtminstone en första positioneringsavsnitt (62), där spetsbasen (23) har enperiferi innefattande åtminstone ett andra positioneringsavsnitt (72), och att detåtminstone ena första positioneringsavsnittet (62) i fördjupningens sidovägg äranordnad att ligga an mot det åtminstone ena andra positioneringsavsnittet (72) hosspetsbasen (23). .Skärverktyget (10) enligt kravet 9 eller 10, varvid fördjupningen (60) har en botten med en upphöjd del (64), där spetsbasen (23) innefattar en fördjupning (74), och därden upphöjda delen (64) hos fördjupningen (60) sträcker sig in i spetsbasens (23)fördjupning (74). .Skärverktyget (10) enligt kravet 11, varvid den upphöjda delen (64) innefattar åtminstone en kant (65), som skjuter ut mot spetsbasen (23). Skärverktyget (10) enligt något av kraven 4 till 12, när krav 5 till 12 är underordnadekravet 4, varvid kroppens radie (38) inte överstiger 4 gånger, företrädesvis 3 gånger,en radie (29) hos den cylindriskt formade delen (26) av spetsen (20). Skärverktyget (10) enligt något av de tidigare kraven, varvid spetsen (20) består avett hårt material med en hårdhet på åtminstone 1100 HV30 och att kroppen (30)består av legerat stål eller verktygsstål med en hårdhet på åtminstone 400 HV30. Skärverktyget (10) enligt något av de tidigare kraven, varvid spetsen (20) innefattarett ojämnt antal spår (40).
Priority Applications (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE1650213A SE539941C2 (sv) | 2016-02-19 | 2016-02-19 | Cutting tool for coal mining, mechanical processing of rocks, use during rotary drilling or working asphalt, concrete or like material, provided with longitudinally extending grooves |
US15/998,975 US10711529B2 (en) | 2016-02-19 | 2017-02-15 | Cutting tool |
CN201780011840.XA CN108699904A (zh) | 2016-02-19 | 2017-02-15 | 在旋转打孔或加工沥青、混凝土或类似材料期间使用的设置有纵向延伸凹槽的用于煤矿开采、岩石的机械加工的切削刀具 |
PCT/SE2017/050141 WO2017142465A1 (en) | 2016-02-19 | 2017-02-15 | Cutting tool for coal mining, mechanical processing of rocks, use during rotary drilling or working asphalt, concrete or like material, provided with longitudinally extending grooves |
RU2018132560A RU2723080C2 (ru) | 2016-02-19 | 2017-02-15 | Режущий инструмент для добычи угля, механической обработки камней, для использования во время роторного бурения или обработки асфальта, бетона или подобных материалов, снабженный удлиненными в продольном направлении канавками |
EP17753579.6A EP3417149B1 (en) | 2016-02-19 | 2017-02-15 | Cutting tool for coal mining, mechanical processing of rocks, use during rotary drilling or working asphalt, concrete or like material, provided with longitudinally extending grooves |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE1650213A SE539941C2 (sv) | 2016-02-19 | 2016-02-19 | Cutting tool for coal mining, mechanical processing of rocks, use during rotary drilling or working asphalt, concrete or like material, provided with longitudinally extending grooves |
Publications (2)
Publication Number | Publication Date |
---|---|
SE1650213A1 SE1650213A1 (sv) | 2017-08-20 |
SE539941C2 true SE539941C2 (sv) | 2018-02-06 |
Family
ID=59625340
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
SE1650213A SE539941C2 (sv) | 2016-02-19 | 2016-02-19 | Cutting tool for coal mining, mechanical processing of rocks, use during rotary drilling or working asphalt, concrete or like material, provided with longitudinally extending grooves |
Country Status (6)
Country | Link |
---|---|
US (1) | US10711529B2 (sv) |
EP (1) | EP3417149B1 (sv) |
CN (1) | CN108699904A (sv) |
RU (1) | RU2723080C2 (sv) |
SE (1) | SE539941C2 (sv) |
WO (1) | WO2017142465A1 (sv) |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
USD920401S1 (en) * | 2018-11-15 | 2021-05-25 | Caterpillar Inc. | Cutting tool |
US11098584B2 (en) * | 2018-11-15 | 2021-08-24 | Caterpillar Inc. | Carbide cutter bit with ribbed sides and conical tip |
CN111101937A (zh) * | 2019-11-26 | 2020-05-05 | 李庆 | 一种可调采矿头 |
USD990269S1 (en) * | 2020-10-12 | 2023-06-27 | Bomag Gmbh | Milling bit |
USD989137S1 (en) * | 2021-08-05 | 2023-06-13 | Element Six Gmbh | Road milling and planing pick tool |
Family Cites Families (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1089611A (en) | 1964-01-10 | 1967-11-01 | Coal Industry Patents Ltd | Coal cutter picks |
SU823515A1 (ru) * | 1979-05-07 | 1981-04-23 | Челябинский Ордена Ленина Заводдорожных Машин Им. Колющенко | Породоразрушающий инструмент |
US5141289A (en) | 1988-07-20 | 1992-08-25 | Kennametal Inc. | Cemented carbide tip |
DE427758T1 (de) * | 1988-07-20 | 1991-11-07 | Kennametal Inc., Latrobe, Pa. | Gesinterte karbidplatte. |
US4981328A (en) | 1989-08-22 | 1991-01-01 | Kennametal Inc. | Rotatable tool having a carbide insert with bumps |
US5551760A (en) * | 1993-09-02 | 1996-09-03 | The Sollami Company | Tungsten carbide insert for a cutting tool |
US6019434A (en) * | 1997-10-07 | 2000-02-01 | Fansteel Inc. | Point attack bit |
DE19803166C2 (de) * | 1998-01-28 | 2000-05-11 | Betek Bergbau & Hartmetall | Rundschaftmeißel für eine Schrämmaschine oder dgl. |
DE19857451A1 (de) * | 1998-12-12 | 2000-06-15 | Boart Hwf Gmbh Co Kg | Schneid- oder Brechwerkzeug sowie Schneideinsatz für dieses |
US7458646B2 (en) | 2006-10-06 | 2008-12-02 | Kennametal Inc. | Rotatable cutting tool and cutting tool body |
US8678517B2 (en) * | 2007-08-23 | 2014-03-25 | Sandvik Intellectual Property Ab | Reduced volume cutting tip and cutting bit incorporating same |
DE102007051911B4 (de) * | 2007-10-29 | 2011-06-16 | Betek Bergbau- Und Hartmetalltechnik Karl-Heinz Simon Gmbh & Co. Kg | Schaftmeißel |
SE532704C2 (sv) | 2008-03-31 | 2010-03-23 | Atlas Copco Secoroc Ab | Förfarande för att öka segheten av stift för ett bergborrverktyg. |
US9476299B2 (en) * | 2008-11-05 | 2016-10-25 | Gregory Greenspan | Mining and demolition tool |
EP2499323A1 (en) | 2009-02-27 | 2012-09-19 | Newtech Drilling Products, LLC. | Drill bit for earth boring |
CN201424622Y (zh) * | 2009-06-10 | 2010-03-17 | 王木义 | 刨路刀具的结构改良 |
CN201857967U (zh) * | 2010-10-15 | 2011-06-08 | 吕增和 | 耐磨防脱头镐型截齿 |
CN102121351A (zh) * | 2010-12-06 | 2011-07-13 | 李仕清 | 一种带定位孔或定位槽或复合定位孔的高效刀头 |
DE102011054393A1 (de) * | 2011-10-11 | 2013-04-11 | Betek Gmbh & Co. Kg | Schaftmeißel |
US9103208B2 (en) | 2012-06-12 | 2015-08-11 | Kennametal Inc. | Cutting bit with hard cutting tip centering and braze joint control feature |
CN104564066A (zh) | 2013-10-12 | 2015-04-29 | 李仕清 | 一种联接齿轮或一体设置齿轮牙的截齿套及配套的截齿 |
CN204511441U (zh) * | 2014-12-27 | 2015-07-29 | 株洲中钨硬质合金有限公司 | 一种防脱头耐磨截齿 |
-
2016
- 2016-02-19 SE SE1650213A patent/SE539941C2/sv unknown
-
2017
- 2017-02-15 WO PCT/SE2017/050141 patent/WO2017142465A1/en active Application Filing
- 2017-02-15 US US15/998,975 patent/US10711529B2/en active Active
- 2017-02-15 CN CN201780011840.XA patent/CN108699904A/zh active Pending
- 2017-02-15 RU RU2018132560A patent/RU2723080C2/ru active
- 2017-02-15 EP EP17753579.6A patent/EP3417149B1/en active Active
Also Published As
Publication number | Publication date |
---|---|
US10711529B2 (en) | 2020-07-14 |
EP3417149C0 (en) | 2024-02-14 |
WO2017142465A1 (en) | 2017-08-24 |
EP3417149A4 (en) | 2019-10-23 |
EP3417149B1 (en) | 2024-02-14 |
RU2018132560A (ru) | 2020-03-19 |
RU2723080C2 (ru) | 2020-06-08 |
EP3417149A1 (en) | 2018-12-26 |
SE1650213A1 (sv) | 2017-08-20 |
CN108699904A (zh) | 2018-10-23 |
US20190292858A1 (en) | 2019-09-26 |
RU2018132560A3 (sv) | 2020-04-24 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
SE539941C2 (sv) | Cutting tool for coal mining, mechanical processing of rocks, use during rotary drilling or working asphalt, concrete or like material, provided with longitudinally extending grooves | |
US8454096B2 (en) | High-impact resistant tool | |
US9458607B2 (en) | Rotatable cutting tool with head portion having elongated projections | |
AU651095B2 (en) | Rotatable cutting tool | |
EP2156003A2 (en) | Method of repairing diamond rock bit | |
US20100163310A1 (en) | Method of manufacturing and repairing fixed-cutter drag-type rotary tools with cutting control structures | |
US10294786B2 (en) | Rotatable cutting tool with cutting insert and bolster | |
US20140216826A1 (en) | Single-waterway drill bits and systems for using same | |
CN102635616A (zh) | 自切扩孔锚栓 | |
US20080053711A1 (en) | Cutting element having a self sharpening tip | |
EP3292274B1 (en) | Cutting tool | |
US20150211365A1 (en) | Multiple Cutters on a Degradation Pick | |
CN202851555U (zh) | 自切扩孔锚栓 | |
AU2015244141B2 (en) | Single-waterway drill bits and systems for using same | |
CN210395061U (zh) | 一种道路工程刀具 | |
CN204754786U (zh) | 铰孔工具 | |
CN100595418C (zh) | 夹石土耐磨抗冲击钻头 | |
CN208276294U (zh) | 一种铰刀 | |
WO2014122440A2 (en) | Rotary tool | |
CN108213583A (zh) | 一种铰刀 | |
CN212601186U (zh) | 一种专用于加工陶瓷砖锚固孔的钻磨头 | |
CA2639315A1 (en) | A cutting element having a self sharpening tip | |
CN204711333U (zh) | 一种孔加工工具 | |
CN202325244U (zh) | 一种凿进钻头 |