CA1162182A - Method for producing an improved layer particular for a drill bit - Google Patents
Method for producing an improved layer particular for a drill bitInfo
- Publication number
- CA1162182A CA1162182A CA000366074A CA366074A CA1162182A CA 1162182 A CA1162182 A CA 1162182A CA 000366074 A CA000366074 A CA 000366074A CA 366074 A CA366074 A CA 366074A CA 1162182 A CA1162182 A CA 1162182A
- Authority
- CA
- Canada
- Prior art keywords
- drill bit
- core member
- wear
- nickel
- cutting teeth
- 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.)
- Expired
Links
- 238000004519 manufacturing process Methods 0.000 title description 3
- 239000000843 powder Substances 0.000 claims abstract description 13
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 10
- 239000000463 material Substances 0.000 claims description 7
- 230000036346 tooth eruption Effects 0.000 claims description 7
- 239000011435 rock Substances 0.000 claims description 6
- 229910052759 nickel Inorganic materials 0.000 claims description 5
- 238000007751 thermal spraying Methods 0.000 claims description 5
- 239000007787 solid Substances 0.000 claims description 4
- 229910000851 Alloy steel Inorganic materials 0.000 claims description 3
- 238000005553 drilling Methods 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 claims description 3
- 238000005096 rolling process Methods 0.000 claims description 3
- 238000000034 method Methods 0.000 abstract description 10
- 239000002184 metal Substances 0.000 abstract 1
- 229920000136 polysorbate Polymers 0.000 abstract 1
- 238000005245 sintering Methods 0.000 description 3
- 239000000919 ceramic Substances 0.000 description 2
- 238000007750 plasma spraying Methods 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000001427 coherent effect Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- MOYKHGMNXAOIAT-JGWLITMVSA-N isosorbide dinitrate Chemical compound [O-][N+](=O)O[C@H]1CO[C@@H]2[C@H](O[N+](=O)[O-])CO[C@@H]21 MOYKHGMNXAOIAT-JGWLITMVSA-N 0.000 description 1
- 238000005488 sandblasting Methods 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
- C23C4/18—After-treatment
-
- 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
-
- 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
- E21B10/50—Drill bits characterised by wear resisting parts, e.g. diamond inserts the bit being of roller type
- E21B10/52—Drill bits characterised by wear resisting parts, e.g. diamond inserts the bit being of roller type with chisel- or button-type inserts
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Mechanical Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Mining & Mineral Resources (AREA)
- Geology (AREA)
- Materials Engineering (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Organic Chemistry (AREA)
- Metallurgy (AREA)
- Fluid Mechanics (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Plasma & Fusion (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Composite Materials (AREA)
- Manufacturing & Machinery (AREA)
- Earth Drilling (AREA)
- Powder Metallurgy (AREA)
- Coating By Spraying Or Casting (AREA)
Abstract
ABSTRACT
An improved method is disclosed of producing an object, such as a drill bit, comprising a core member having a compacted and sintered metal powder layer thereon and a wear-resistant layer isostatically hot compacted over portions of the powder layer. The method enables improved bonding be-tween the layers and between the powder layer and the core, giving rise to very high resistance to wear and to chipping.
An improved method is disclosed of producing an object, such as a drill bit, comprising a core member having a compacted and sintered metal powder layer thereon and a wear-resistant layer isostatically hot compacted over portions of the powder layer. The method enables improved bonding be-tween the layers and between the powder layer and the core, giving rise to very high resistance to wear and to chipping.
Description
1 1 6~82 The invention relates to a method for producing an object on which an exterior layer is applied by thermal spraying, followed by a heat treatment, and to the object, in particular a drill bit, obtained pursuant to this method.
Such a method is disclosed in British Patent 1,367,762. In applica-tion of the method described above to objects wherein it is required that the exterior layer applied be capable, in operation, of withstanding great vari-able forces, for example, that it must be resistant to wear, however, it happens that this layer sometimes chips off, thus shortening the life of the object obtained.
The invention accordingly provides a method for producing an object on which an exterior layer is applied by thermal spraying, followed by a heat treatment, which method comprises applying by cold isostatic compacting a layer of a suitable powder material on a core member, sintering the resultant structure, thereafter applying an exterior layer which is a wear-resistant layer, and then isostat;cally hot compacting the obtained structure.
It has been found that a suitable powder material for this purpose is a nickel-containing alloy steel powder preferably containing 3.5% nickel therein.
The invention in addition provides a drill bit with cutting teeth provided with a wear-resistant layer, for drilling in rock.
In one embodiment of the method pursuant to the invention a supply of powder material is introduced into a rubber mold and distributed, after which the core member, which is usually formed of a bearing steel, is placed in the powder, following which the powder is pressed on. The core member may alternatively be placed in the mold first, after which the powder material is introduced and pressed on. The mold is closed and is then isostatically com-1 J 621~
pacted cold until a coherent member having a density of approximately 90% is obtained. The compact removed from the mold is then sintered in a furnace.
After cooling the sintered object is coated with a wear-resistant layer by thermal spraying, for example plasma spraying, after which the structure thus obtained is isostatically compacted hot. This hot isostatic compacting may be done by inserting the entire object in a thin-walled deep-drawn vessel or con-tainer of low-carbon steel having a wall thickness of approximately 0.5 mm, filled with a ceramic powder. This vessel is then heated and subjected to pressure on all sides. After hot isostatic compacting the object may be readily separated from the surrounding ceramic mass and cleaned by sand blast-ing, This method proves to provide components with accurately shaped dimen-sions comparable to those of a forged product.
When a drill bit for rock is produced in this fashion, after sinter-ing not the entire surface of the cutting teeth but only the parts or surfaces thereof which come directly into contact with the rock are coated with the wear-resistant layer by thermal spraying. Pollowing the selective application of the wear-resistant layer the preformed drill bit is subjected in its en-tirety to hot isostatic compacting, as described above.
The invention will now be explained in greater detail by means of the accompanying drawing, in which:
Figure 1 is a cross section of a drill bit produced according to a preferred embodiment of the invcntion.
Figure 2 is a perspective view of a portion of this drill bit.
The drill bit 1 shown in Figure 1 is composed of a core member 3, made of a bearing material, in which are applied races 2 for rolling elements ~not shown). On this core member 3, solid at the beginning, is applied in a rubber mold a layer 4 of powder, which combination is then isostatically com-1 J ~3L82 pacted cold. This operation takes place preferably under a pressure ofapproximately 6000 atmospheres at room temperature. Then the preformed drill bit, isostatically compacted cold, is removed from the mold and sintered in a sintering furnace at a temperature of approx. 1200C at 1 atnnosphere under reduction by hydrogen for approx. 1 hour, which operations lead to a density of approx. 90% of the compacted material. Then, by means of plasma spraying technique, the wear-resistan~ layer 5 is applied on the layer 4 and the object obtained is then inserted into a vessel or container and isostatically com-pacted hot under a pressure of for example approx. 1600 atmospheres and at a temperature of approx. 1100C for at least 2 hours. This operation results in a density of the layers 4 and 5 of 99% and a very solid bond between the layers.
It will be found by the method pursuant to the invention that the mechanical properties of the drill bit thus formed are greatly improved, like the bond between the layers 4 and 5, on the one hand, and between the layer 4 and the core member 3, on the other. By this means the desired effect of very high resistance to wear and resistance to chipping of the cutting teeth is ob-tained, combined with a core member which functionally has other possible applications, such as, for example, the function of a bearing.
It is noted that the original solid core member 3, after mechanical operations and heat treatmènt, acquires the shape, as represented in Figure 1, in which the races 2 of the rolling elements are supplied.
It may be seen further from Figure 2 that not the entire surface of the cutting teeth of the drill bit is provided with the wear-resistant layer 5, but that the wear-resistant layer is applied only on the places or surfaces where the tooth comes directly into contact with rock during operation.
Thus there is provided by the invention a device, such as a drill i 8 2 bit, which in principle consists of three parts, namely a significantly im-proved cutting part 5, a supporting part 4 and a core or bearing part 3, which parts are combined in an economically and technically advantageous manner such that the said drill bit satisfies the requirements set.
Such a method is disclosed in British Patent 1,367,762. In applica-tion of the method described above to objects wherein it is required that the exterior layer applied be capable, in operation, of withstanding great vari-able forces, for example, that it must be resistant to wear, however, it happens that this layer sometimes chips off, thus shortening the life of the object obtained.
The invention accordingly provides a method for producing an object on which an exterior layer is applied by thermal spraying, followed by a heat treatment, which method comprises applying by cold isostatic compacting a layer of a suitable powder material on a core member, sintering the resultant structure, thereafter applying an exterior layer which is a wear-resistant layer, and then isostat;cally hot compacting the obtained structure.
It has been found that a suitable powder material for this purpose is a nickel-containing alloy steel powder preferably containing 3.5% nickel therein.
The invention in addition provides a drill bit with cutting teeth provided with a wear-resistant layer, for drilling in rock.
In one embodiment of the method pursuant to the invention a supply of powder material is introduced into a rubber mold and distributed, after which the core member, which is usually formed of a bearing steel, is placed in the powder, following which the powder is pressed on. The core member may alternatively be placed in the mold first, after which the powder material is introduced and pressed on. The mold is closed and is then isostatically com-1 J 621~
pacted cold until a coherent member having a density of approximately 90% is obtained. The compact removed from the mold is then sintered in a furnace.
After cooling the sintered object is coated with a wear-resistant layer by thermal spraying, for example plasma spraying, after which the structure thus obtained is isostatically compacted hot. This hot isostatic compacting may be done by inserting the entire object in a thin-walled deep-drawn vessel or con-tainer of low-carbon steel having a wall thickness of approximately 0.5 mm, filled with a ceramic powder. This vessel is then heated and subjected to pressure on all sides. After hot isostatic compacting the object may be readily separated from the surrounding ceramic mass and cleaned by sand blast-ing, This method proves to provide components with accurately shaped dimen-sions comparable to those of a forged product.
When a drill bit for rock is produced in this fashion, after sinter-ing not the entire surface of the cutting teeth but only the parts or surfaces thereof which come directly into contact with the rock are coated with the wear-resistant layer by thermal spraying. Pollowing the selective application of the wear-resistant layer the preformed drill bit is subjected in its en-tirety to hot isostatic compacting, as described above.
The invention will now be explained in greater detail by means of the accompanying drawing, in which:
Figure 1 is a cross section of a drill bit produced according to a preferred embodiment of the invcntion.
Figure 2 is a perspective view of a portion of this drill bit.
The drill bit 1 shown in Figure 1 is composed of a core member 3, made of a bearing material, in which are applied races 2 for rolling elements ~not shown). On this core member 3, solid at the beginning, is applied in a rubber mold a layer 4 of powder, which combination is then isostatically com-1 J ~3L82 pacted cold. This operation takes place preferably under a pressure ofapproximately 6000 atmospheres at room temperature. Then the preformed drill bit, isostatically compacted cold, is removed from the mold and sintered in a sintering furnace at a temperature of approx. 1200C at 1 atnnosphere under reduction by hydrogen for approx. 1 hour, which operations lead to a density of approx. 90% of the compacted material. Then, by means of plasma spraying technique, the wear-resistan~ layer 5 is applied on the layer 4 and the object obtained is then inserted into a vessel or container and isostatically com-pacted hot under a pressure of for example approx. 1600 atmospheres and at a temperature of approx. 1100C for at least 2 hours. This operation results in a density of the layers 4 and 5 of 99% and a very solid bond between the layers.
It will be found by the method pursuant to the invention that the mechanical properties of the drill bit thus formed are greatly improved, like the bond between the layers 4 and 5, on the one hand, and between the layer 4 and the core member 3, on the other. By this means the desired effect of very high resistance to wear and resistance to chipping of the cutting teeth is ob-tained, combined with a core member which functionally has other possible applications, such as, for example, the function of a bearing.
It is noted that the original solid core member 3, after mechanical operations and heat treatmènt, acquires the shape, as represented in Figure 1, in which the races 2 of the rolling elements are supplied.
It may be seen further from Figure 2 that not the entire surface of the cutting teeth of the drill bit is provided with the wear-resistant layer 5, but that the wear-resistant layer is applied only on the places or surfaces where the tooth comes directly into contact with rock during operation.
Thus there is provided by the invention a device, such as a drill i 8 2 bit, which in principle consists of three parts, namely a significantly im-proved cutting part 5, a supporting part 4 and a core or bearing part 3, which parts are combined in an economically and technically advantageous manner such that the said drill bit satisfies the requirements set.
Claims (4)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A drill bit with cutting teeth for drilling in rock comprising:
a core member having raceways for rolling elements for rotation of the drill bit, a supporting layer exteriorly shaped to define cutting teeth and formed of highly compacted sintered powder material of substantially 90% density, isostatically bonded to said core member, a wear resistant layer applied by thermal spraying and covering only the portions of the cutting teeth which upon drilling directly contact the rock, said wear resistant layer and said supporting layer being iso-statically hot compacted which combined are of substantially 99% density, said layers having a solid bond therebetween providing a drill bit of superior mechanical properties including high resistance to wear and chipping.
a core member having raceways for rolling elements for rotation of the drill bit, a supporting layer exteriorly shaped to define cutting teeth and formed of highly compacted sintered powder material of substantially 90% density, isostatically bonded to said core member, a wear resistant layer applied by thermal spraying and covering only the portions of the cutting teeth which upon drilling directly contact the rock, said wear resistant layer and said supporting layer being iso-statically hot compacted which combined are of substantially 99% density, said layers having a solid bond therebetween providing a drill bit of superior mechanical properties including high resistance to wear and chipping.
2. A drill bit as claimed in claim 1 wherein the said supporting layer consists of a nickel-containing alloy steel.
3. A drill bit as claimed in claim 2 wherein said nickel-containing alloy steel contains about 3.5% nickel.
4. A drill bit as claimed in claim 1 wherein said core member is formed by mechanical operations and heat treatment into a bearing for the bearing system of the drill bit.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL7908745A NL7908745A (en) | 1979-12-04 | 1979-12-04 | METHOD FOR MANUFACTURING AN ARTICLE APPLIED BY THERMAL SPRAYING AND OBJECT, IN PARTICULAR A DRILLING CHISEL, OBTAINED BY THIS METHOD |
| NL7908745 | 1979-12-04 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1162182A true CA1162182A (en) | 1984-02-14 |
Family
ID=19834277
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000366074A Expired CA1162182A (en) | 1979-12-04 | 1980-12-03 | Method for producing an improved layer particular for a drill bit |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP0030055B1 (en) |
| JP (1) | JPS5697093A (en) |
| AU (1) | AU539718B2 (en) |
| CA (1) | CA1162182A (en) |
| DE (1) | DE3071100D1 (en) |
| NL (1) | NL7908745A (en) |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58223676A (en) * | 1982-03-05 | 1983-12-26 | ロ−ルス−ロイス・リミテツド | Composite product and manufacture |
| DE3318999A1 (en) * | 1983-05-25 | 1984-11-29 | M.A.N. Maschinenfabrik Augsburg-Nürnberg AG, 8000 München | COATED METAL OBJECT AND METHOD FOR THE PRODUCTION THEREOF |
| US4597456A (en) * | 1984-07-23 | 1986-07-01 | Cdp, Ltd. | Conical cutters for drill bits, and processes to produce same |
| US4562892A (en) * | 1984-07-23 | 1986-01-07 | Cdp, Ltd. | Rolling cutters for drill bits |
| US4861546A (en) * | 1987-12-23 | 1989-08-29 | Precision Castparts Corp. | Method of forming a metal article from powdered metal |
| DE19747385A1 (en) * | 1997-10-27 | 1999-04-29 | Linde Ag | Manufacture of molded parts |
| WO1999023272A1 (en) * | 1997-11-03 | 1999-05-14 | Siemens Aktiengesellschaft | Method for producing a protective coating on a base body intended to be impinged upon by a hot gas and corresponding product |
| US6878412B2 (en) | 2001-03-26 | 2005-04-12 | Bodycote Imt, Inc. | Corrosion resistant component and method for fabricating same |
| US6615935B2 (en) | 2001-05-01 | 2003-09-09 | Smith International, Inc. | Roller cone bits with wear and fracture resistant surface |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL54863C (en) * | 1900-01-01 | |||
| FR1434158A (en) * | 1964-11-25 | 1966-04-08 | Sfec | Improvements to refractory protective coatings, and method of manufacturing these elements |
| GB1367762A (en) * | 1971-09-17 | 1974-09-25 | Ass Eng Ltd | cermet materials |
| US3882581A (en) * | 1974-03-13 | 1975-05-13 | Minnesota Mining & Mfg | Coated, partially laminated carbide cutting tool insert |
| JPS5347307A (en) * | 1976-10-13 | 1978-04-27 | Tone Boring Co | Tricone bit cone and process for production thereof |
| NL7703234A (en) * | 1977-03-25 | 1978-09-27 | Skf Ind Trading & Dev | METHOD FOR MANUFACTURING A DRILL CHUCK INCLUDING HARD WEAR-RESISTANT ELEMENTS, AND DRILL CHAPTER MADE ACCORDING TO THE METHOD |
| NL7804454A (en) * | 1978-04-26 | 1979-10-30 | Skf Ind Trading & Dev | METHOD OF APPLYING A DENSE LAYER OF CERAMIC METAL OR CERMETS ON A METAL ARTICLE |
-
1979
- 1979-12-04 NL NL7908745A patent/NL7908745A/en not_active Application Discontinuation
-
1980
- 1980-11-14 AU AU64386/80A patent/AU539718B2/en not_active Ceased
- 1980-11-24 DE DE8080201107T patent/DE3071100D1/en not_active Expired
- 1980-11-24 EP EP19800201107 patent/EP0030055B1/en not_active Expired
- 1980-12-03 JP JP16970880A patent/JPS5697093A/en active Granted
- 1980-12-03 CA CA000366074A patent/CA1162182A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| AU539718B2 (en) | 1984-10-11 |
| DE3071100D1 (en) | 1985-10-24 |
| EP0030055B1 (en) | 1985-09-18 |
| AU6438680A (en) | 1981-06-11 |
| JPS6343550B2 (en) | 1988-08-31 |
| NL7908745A (en) | 1981-07-01 |
| EP0030055A1 (en) | 1981-06-10 |
| JPS5697093A (en) | 1981-08-05 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |