EP0052584A1 - Verfahren zur Herstellung eines Stahlkörpers mit Hartmetalleinsätzen - Google Patents
Verfahren zur Herstellung eines Stahlkörpers mit Hartmetalleinsätzen Download PDFInfo
- Publication number
- EP0052584A1 EP0052584A1 EP81850192A EP81850192A EP0052584A1 EP 0052584 A1 EP0052584 A1 EP 0052584A1 EP 81850192 A EP81850192 A EP 81850192A EP 81850192 A EP81850192 A EP 81850192A EP 0052584 A1 EP0052584 A1 EP 0052584A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- steel
- inserts
- hard material
- steel powder
- material inserts
- 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.)
- Withdrawn
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 48
- 239000010959 steel Substances 0.000 title claims abstract description 48
- 239000000463 material Substances 0.000 title claims abstract description 27
- 238000000034 method Methods 0.000 title claims abstract description 21
- 239000000843 powder Substances 0.000 claims abstract description 30
- 238000005245 sintering Methods 0.000 claims abstract description 14
- 239000002184 metal Substances 0.000 claims description 19
- 229910052751 metal Inorganic materials 0.000 claims description 19
- 239000000203 mixture Substances 0.000 claims description 9
- 229910052759 nickel Inorganic materials 0.000 claims description 9
- 229910052799 carbon Inorganic materials 0.000 claims description 6
- 238000005056 compaction Methods 0.000 claims description 6
- 229910052802 copper Inorganic materials 0.000 claims description 6
- 239000010432 diamond Substances 0.000 claims description 5
- 239000010410 layer Substances 0.000 claims description 5
- 239000002344 surface layer Substances 0.000 claims description 5
- 229910000851 Alloy steel Inorganic materials 0.000 claims 1
- 238000005242 forging Methods 0.000 claims 1
- 238000005553 drilling Methods 0.000 abstract description 4
- 229910045601 alloy Inorganic materials 0.000 abstract description 3
- 239000000956 alloy Substances 0.000 abstract description 3
- 239000011435 rock Substances 0.000 abstract description 3
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 12
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 8
- 239000010949 copper Substances 0.000 description 5
- 229910052742 iron Inorganic materials 0.000 description 4
- 229910052750 molybdenum Inorganic materials 0.000 description 4
- 238000005219 brazing Methods 0.000 description 3
- 230000004907 flux Effects 0.000 description 3
- 238000003754 machining Methods 0.000 description 3
- 150000001247 metal acetylides Chemical class 0.000 description 3
- 210000003739 neck Anatomy 0.000 description 3
- 230000001681 protective effect Effects 0.000 description 3
- 239000007779 soft material Substances 0.000 description 3
- 238000003466 welding Methods 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000011010 flushing procedure Methods 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910000760 Hardened steel Inorganic materials 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 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
- 238000007796 conventional method Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 229910003460 diamond Inorganic materials 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 239000003999 initiator Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 238000004663 powder metallurgy Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Images
Classifications
-
- 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
- E21B10/46—Drill bits characterised by wear resisting parts, e.g. diamond inserts
- E21B10/56—Button-type inserts
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F7/00—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression
- B22F7/06—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of composite workpieces or articles from parts, e.g. to form tipped tools
Definitions
- the present invention relates to a method of producing a steel body com prising hard material inserts, e.g. producing drill bits for rock drilling.
- the object of the present invention is to provide a method of producing a steel body comprising hard material inserts which method avoids machining to close tolerances and where the strength of the final product is not limited by the strength of a soft material between the steel body and the hard material inserts.
- no machining marks are present on the inside of the steel hole to act as stress raisers and fatigue initiators.
- the invention also guarantees full support of the bottom of the buttons. The invention also makes it possible to reduce the amount of hard metal inside the steel, resulting in improved economy.
- the invention which is defined by the subsequent claims, fulfills the above mentioned object by prescribing that steel powder is compacted from a cold state to a high density preform comprising the hard material inserts and that the composition of the steel powder is chosen such that it undergoes substantial shrinkage during the subsequent sintering.
- the steel powder is compacted by the impact of a high velocity punch, whereby a considerably higher and more uniform density is obtained than with conventional pressing techniques. This applies especially to the regions nearest to the hard material inserts where an adequate powder flow is not obtained with conventional techniques.
- the hard material inserts may, furthermore, be advantageously provided with surface irregularities, e.g. being rough as compacted and sintered, or otherwise such shaped that they become mechanically locked in the steel body through the compaction.
- a layer of metal e.g. electro-plated nickel, iron or cobalt
- the metal layer may be deposited on the hard material inserts in any suitable way.
- a further advantage with the present invention is obtained if the composition of the steel powder is varied so that a sub-surface layer of lower hardness is obtained. Such a layer would be rapidly removed during operation after the surface layer of normal hardness has been worn down, whereby the self-sharpening of the drill bit is improved.
- This lower hardness may be obtained through decreasing the copper or carbon content of the alloy, or increasing the nickel content. Variation in hardness may also be used to increase resistance to gauge wear.
- hard material in the present application mostly refers to hard metals, e.g. various metal carbides
- the term also includes other suitable hard materials e.g. other carbides or diamonds.
- hard material inserts which comprise hard metal discs having a surface layer of sintered diamonds. This diamond layer is protected during sintering by nickel plating of the hard metal and the diamonds. Alternatively, the sintering temperature may be reduced.
- a further advantage obtained with the present invention is that the hard material inserts can have almost any form. This means that they can be given a form which is optimized for a particular application. Furthermore, it is possible to obtain a steel body comprising hard material inserts with an overall strength which up to now has been believed to be unobtainable with powder metallurgy.
- the method according to the present invention is performed in the following way.
- the preformed hard material inserts are placed on a conventional die in the desired pattern.
- the die is then placed in a compaction chamber.
- Steel powder preferably with the above mentioned composition, is then added around the inserts. Normally the lowermost part of the inserts will extend outside the volume of powder.
- the steel powder is covered by another die or a thin disc. After this the powder is compacted from a cold state to a high density preform. This is preferably performed by means of a high velocity punch, which impacts the powder. Experiments have shown that good results are obtainable in the speed range 100-600 m/s. After compaction the preform is sintered.
- Sintering should take place at a temperature in the range 1100 to 1250°C and last for 1/2-3 hours. These values depend somewhat on the composition of the alloy and the type of fixation required. A steel powder with the above mentioned composition will, during sintering, undergo a substantial shrinkage, 0.5-2 %. In order to improve the fixation of the inserts a chemical bond between the hard material and the steel may be produced by the use of a flux on the interface of the two materials. After sintering the compact may be either furnace cooled or air cooled or quenched in an oil bath or similar.
- the back face is machined flat and then friction welded to a steel tube. No special techniques are required for the friction welding. Good results have been obtained with a rotation speed of 1500 rpm, a welding time of 10 seconds and a contact pressure of 20 bar. After this the part is machined to get rid of the weld burr and to obtain the flushing holes.
- the part is also provided with a thread or other suitable fitment for connection to a drill r od . It is desirable, although not necessary, to temper the finished bit at a temperature of about 200°C.
- fig. 1 shows a drill bit for rock drilling produced according to the invention.
- Figs . 2-5 show different embodiments of the drill bit from below.
- Figs. 6-11 show a number of alternative shapes of hard material inserts for drill bits.
- the drill bit according to Fig. 1 comprises a head portion 1 comprising a number of hard metal inserts 2. This part of the drill bit has been manufactured with the method according to the invention. Head portion 1 has been connected with a steel tube 3 by friction welding. The drill has further been provided with a thread 4 for the connection with a drill string and a channel 5 for flushing fluid. As can be seen in figs. 2-5 virtually any cross-sectional form can be used for the inserts. In addition to the forms shown almost any prior art form may be used. In figs. 6-11 a number of alternative inserts are shown. These inserts, which are only a few examples of possible forms, have circular cross-sectional areas although they may have other cross-sectional forms, e.g.
- Fig. 6 shows an insert having negative taper.
- Fig. 7 shows an insert having a rough surface.
- fig. 8 the insert is provided with a neck or waist.
- fig. 9 the insert is provided with several necks.
- the insert in fig. 10 has a form similar to that of a human tooth.
- the insert shown in fig. 11 is additionally provided with a neck.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Mining & Mineral Resources (AREA)
- Geology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Physics & Mathematics (AREA)
- Materials Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Fluid Mechanics (AREA)
- Manufacturing & Machinery (AREA)
- Composite Materials (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Earth Drilling (AREA)
- Powder Metallurgy (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE8007961 | 1980-11-13 | ||
SE8007961A SE423562B (sv) | 1980-11-13 | 1980-11-13 | Forfarande for framstellning av en stalkropp innefattande insatser av hart material |
Publications (1)
Publication Number | Publication Date |
---|---|
EP0052584A1 true EP0052584A1 (de) | 1982-05-26 |
Family
ID=20342228
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP81850192A Withdrawn EP0052584A1 (de) | 1980-11-13 | 1981-10-19 | Verfahren zur Herstellung eines Stahlkörpers mit Hartmetalleinsätzen |
Country Status (5)
Country | Link |
---|---|
EP (1) | EP0052584A1 (de) |
JP (1) | JPS57101602A (de) |
BR (1) | BR8107342A (de) |
SE (1) | SE423562B (de) |
ZA (1) | ZA817340B (de) |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0111600A1 (de) * | 1982-12-13 | 1984-06-27 | Reed Rock Bit Company | Schneidkörper |
FR2542649A1 (fr) * | 1983-03-19 | 1984-09-21 | Krupp Gmbh | Procede de fabrication d'un corps composite expose a une usure, notamment par abrasion |
EP0142941A1 (de) * | 1983-10-24 | 1985-05-29 | Smith International, Inc. | Konisches Gesteinsschneidwerkzeug mit metallisch gebundenen Schneideinsätzen |
EP0157625A2 (de) * | 1984-04-03 | 1985-10-09 | Sumitomo Electric Industries Limited | Werkzeug aus Verbundwerkstoff |
EP0169718A2 (de) * | 1984-07-23 | 1986-01-29 | CDP, Ltd. | Kegelförmiger Schneidkopf für Bohrmeissel und Verfahren seiner Herstellung |
US4593776A (en) * | 1984-03-28 | 1986-06-10 | Smith International, Inc. | Rock bits having metallurgically bonded cutter inserts |
EP0194504A2 (de) * | 1985-02-26 | 1986-09-17 | Kabushiki Kaisha Toshiba | Verbundkörper und Verfahren zu seiner Herstellung |
EP0260850A2 (de) * | 1986-09-18 | 1988-03-23 | The British Petroleum Company p.l.c. | Verbundmaterial mit kontinuierlicher Änderung der Zusammensetzung |
WO2000056487A1 (de) * | 1999-03-20 | 2000-09-28 | Karl Simon Gmbh & Co. Kg | Verfahren zum herstellen einer fräslamelle und nach dem verfahren hergestellte fräslamelle |
WO2011146955A3 (de) * | 2010-05-26 | 2012-05-03 | Dywidag-Systems International Gmbh | Bohrkrone |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6311788A (ja) * | 1986-07-01 | 1988-01-19 | 川崎重工業株式会社 | ロツクビツトコ−ン及びその製造方法 |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB530639A (en) * | 1938-06-16 | 1940-12-17 | Meutsch Voigtlaender & Co | Process for the production of articles provided with coatings or insets of hard metal |
US3673676A (en) * | 1970-05-13 | 1972-07-04 | Exxon Production Research Co | Method for forming tool assembly |
US3837068A (en) * | 1971-06-14 | 1974-09-24 | Federal Mogul Corp | Method of making a composite high-strength sleeve |
FR2384574A1 (fr) * | 1977-03-25 | 1978-10-20 | Skf Ind Trading & Dev | Procede pour la fabrication d'une tete de forage pourvue d'elements durs et resistant a l'usure, et tete de forage obtenue a l'aide de ce procede |
US4164527A (en) * | 1974-11-01 | 1979-08-14 | Bakul Valentin N | Method of making superhard articles |
GB2017153A (en) * | 1978-03-13 | 1979-10-03 | Krupp Gmbh | Method of Producing Composite Hard Metal Bodies |
-
1980
- 1980-11-13 SE SE8007961A patent/SE423562B/sv unknown
-
1981
- 1981-10-19 EP EP81850192A patent/EP0052584A1/de not_active Withdrawn
- 1981-10-23 ZA ZA817340A patent/ZA817340B/xx unknown
- 1981-10-28 JP JP56171515A patent/JPS57101602A/ja active Pending
- 1981-11-12 BR BR8107342A patent/BR8107342A/pt unknown
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB530639A (en) * | 1938-06-16 | 1940-12-17 | Meutsch Voigtlaender & Co | Process for the production of articles provided with coatings or insets of hard metal |
US3673676A (en) * | 1970-05-13 | 1972-07-04 | Exxon Production Research Co | Method for forming tool assembly |
US3837068A (en) * | 1971-06-14 | 1974-09-24 | Federal Mogul Corp | Method of making a composite high-strength sleeve |
US4164527A (en) * | 1974-11-01 | 1979-08-14 | Bakul Valentin N | Method of making superhard articles |
FR2384574A1 (fr) * | 1977-03-25 | 1978-10-20 | Skf Ind Trading & Dev | Procede pour la fabrication d'une tete de forage pourvue d'elements durs et resistant a l'usure, et tete de forage obtenue a l'aide de ce procede |
GB2017153A (en) * | 1978-03-13 | 1979-10-03 | Krupp Gmbh | Method of Producing Composite Hard Metal Bodies |
Cited By (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0111600A1 (de) * | 1982-12-13 | 1984-06-27 | Reed Rock Bit Company | Schneidkörper |
FR2542649A1 (fr) * | 1983-03-19 | 1984-09-21 | Krupp Gmbh | Procede de fabrication d'un corps composite expose a une usure, notamment par abrasion |
EP0142941A1 (de) * | 1983-10-24 | 1985-05-29 | Smith International, Inc. | Konisches Gesteinsschneidwerkzeug mit metallisch gebundenen Schneideinsätzen |
US4593776A (en) * | 1984-03-28 | 1986-06-10 | Smith International, Inc. | Rock bits having metallurgically bonded cutter inserts |
US4950557A (en) * | 1984-04-03 | 1990-08-21 | Sumitomo Electric Industries, Ltd. | Composite tool and a process for the production of the same |
EP0157625A3 (en) * | 1984-04-03 | 1986-06-18 | Sumitomo Electric Industries Limited | Composite tool |
EP0157625A2 (de) * | 1984-04-03 | 1985-10-09 | Sumitomo Electric Industries Limited | Werkzeug aus Verbundwerkstoff |
US4890782A (en) * | 1984-04-03 | 1990-01-02 | Sumitomo Electric Industries, Ltd. | Process for the production of a composite tool |
EP0169718A2 (de) * | 1984-07-23 | 1986-01-29 | CDP, Ltd. | Kegelförmiger Schneidkopf für Bohrmeissel und Verfahren seiner Herstellung |
EP0169718A3 (en) * | 1984-07-23 | 1987-01-21 | Cdp, Ltd. | Conical cutters for drill bits and processes to produce same |
EP0194504A2 (de) * | 1985-02-26 | 1986-09-17 | Kabushiki Kaisha Toshiba | Verbundkörper und Verfahren zu seiner Herstellung |
EP0194504A3 (en) * | 1985-02-26 | 1987-02-04 | Kabushiki Kaisha Toshiba | Composite body and method of manufacturing the same |
US4857411A (en) * | 1985-02-26 | 1989-08-15 | Kabushiki Kaisha Toshiba | Composite body and method of manufacturing the same |
US4859542A (en) * | 1986-09-18 | 1989-08-22 | The British Petroleum Company P.L.C. | Graded structure composites |
EP0260850A3 (en) * | 1986-09-18 | 1988-12-14 | The British Petroleum Company P.L.C. | Graded structure composites |
EP0260850A2 (de) * | 1986-09-18 | 1988-03-23 | The British Petroleum Company p.l.c. | Verbundmaterial mit kontinuierlicher Änderung der Zusammensetzung |
AU601764B2 (en) * | 1986-09-18 | 1990-09-20 | Dresser Industries Inc. | Graded structure composites |
WO2000056487A1 (de) * | 1999-03-20 | 2000-09-28 | Karl Simon Gmbh & Co. Kg | Verfahren zum herstellen einer fräslamelle und nach dem verfahren hergestellte fräslamelle |
GB2366297A (en) * | 1999-03-20 | 2002-03-06 | Simon Karl Gmbh & Co Kg | Method for producing a milling disc and milling disc produced according to the inventive method |
GB2366297B (en) * | 1999-03-20 | 2003-08-27 | Simon Karl Gmbh & Co Kg | Method for manufacturing a milling disc and milling disc manufactured according to the method |
US6723277B1 (en) | 1999-03-20 | 2004-04-20 | Karl Simon Gmbh & Co. Kg | Method for producing a milling disc and milling disc produced according to the inventive method |
WO2011146955A3 (de) * | 2010-05-26 | 2012-05-03 | Dywidag-Systems International Gmbh | Bohrkrone |
Also Published As
Publication number | Publication date |
---|---|
SE423562B (sv) | 1982-05-10 |
ZA817340B (en) | 1982-10-27 |
JPS57101602A (en) | 1982-06-24 |
BR8107342A (pt) | 1982-08-03 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Designated state(s): AT BE CH DE FR GB IT LU NL |
|
17P | Request for examination filed |
Effective date: 19821020 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
|
18D | Application deemed to be withdrawn |
Effective date: 19840424 |
|
RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: DEREK, RAYBOULD |