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EP0030055A1 - Method for producing an improved layer, particular for a drill bit - Google Patents

Method for producing an improved layer, particular for a drill bit Download PDF

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Publication number
EP0030055A1
EP0030055A1 EP19800201107 EP80201107A EP0030055A1 EP 0030055 A1 EP0030055 A1 EP 0030055A1 EP 19800201107 EP19800201107 EP 19800201107 EP 80201107 A EP80201107 A EP 80201107A EP 0030055 A1 EP0030055 A1 EP 0030055A1
Authority
EP
European Patent Office
Prior art keywords
layer
drill bit
core member
nickel
wear
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.)
Granted
Application number
EP19800201107
Other languages
German (de)
French (fr)
Other versions
EP0030055B1 (en
Inventor
Hans Bertil Van Nederveen
Martin Bastiaan Verburgh
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
SKF Industrial Trading and Development Co BV
Original Assignee
SKF Industrial Trading and Development Co BV
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by SKF Industrial Trading and Development Co BV filed Critical SKF Industrial Trading and Development Co BV
Publication of EP0030055A1 publication Critical patent/EP0030055A1/en
Application granted granted Critical
Publication of EP0030055B1 publication Critical patent/EP0030055B1/en
Expired legal-status Critical Current

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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

Definitions

  • 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 an object, in particular a drill bit, obtained pursuant to this method.
  • the invention accordingly procures a method of the type mentioned at the beginning, characterized in that on a core member is applied, by cold isostatic compacting, a layer of a suitable powder material, followed by sintering, after which the exterior layer, which is a wear-resistant layer, is applied and then the structure thus obtained is isostatically compacted hot.
  • a suitable powder material for this purpose is a nickel-containing alloy steel powder with preferably 3.5% nickel therein.
  • the invention in addition procures a drill bit with cutting teeth provided with a wear-resistant layer, for drilling in rock.
  • a supply of powder material is introduced into a rubber mold and distributed, after which the core member, which is usually a type of steel suitable for a bearing, 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 compacted 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 container of low-carbon steel having a wall thickness of approximately 0.5 mm, filled with a ceramic powder. This vessel is then heated and placed under pressure on all sides. After hot isostatic compacting the object may be readily separated from the surrounding ceramic mass and cleaned by sand blasting. This method proves to procure components with accurately shaped dimensions comparable to those of a forged product.
  • the drill bit 1 shown in Fig. 1 is composed of a core member 3 , made of a bearing material, in which are applied the races 2 for the folling elements(not shown).
  • a core member 3 made of a bearing material, in which are applied the races 2 for the folling elements(not shown).
  • the preformed drill bit, isostatically compacted cold is removed from the mold and sintered in a sintering furnace at a temperature of approx. 1200°C at 1 atmosphere under reduction by hydrogen for approx. I hour, which operations lead to a density of approx. 90% of the compacted material.
  • the wear-resistant layer 5 is applied on the layer 4 and the object obtained is then inserted into a vessel or container and isostatically compacted hot under a pressure of for example approx. 1600 atmospheres and at a temperature of approx. 1100°C 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.
  • the original solid core member 3 after mechanical operations and heat treatment, acquires the shape, as represented in Fig. 1, in which the races 2 of the rolling elements are supplied.
  • a device such as a drill bit, which in principle consists of three parts, namely, a significantly improved 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.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Mining & Mineral Resources (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Environmental & Geological Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Plasma & Fusion (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)
  • Coating By Spraying Or Casting (AREA)

Abstract

Process for producing an article, e.g. a drill bit, wherein a first layer (4) of powder material is applied to a core member (3) by cold isostatic compacting and subsequent sintering, and a second, exterior layer (5) is then applied by thermal spraying followed by hot isostatic compacting. The powder material of the first layer (4) may be a nickel-containing alloy steel powder.

Description

  • Method for producing an object on which an exterior layer is applied by thermal spraying and object, in particular a drill bit, obtained pursuant to this method. f
  • 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 an object, in particular a drill bit, obtained pursuant to this method.
  • Such a method is disclosed in British Patent 1,367,762. In application of the method described above to objects wherein it is required that the exterior layer applied be capable, in operation, of withstanding great variable 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 procures a method of the type mentioned at the beginning, characterized in that on a core member is applied, by cold isostatic compacting, a layer of a suitable powder material, followed by sintering, after which the exterior layer, which is a wear-resistant layer, is applied and then the structure thus obtained is isostatically compacted hot.
  • It has been found that a suitable powder material for this purpose is a nickel-containing alloy steel powder with preferably 3.5% nickel therein.
  • The invention in addition procures a drill bit with cutting teeth provided with a wear-resistant layer, for drilling in rock.
  • For the performance of a 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 a type of steel suitable for a bearing, 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 compacted 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 container of low-carbon steel having a wall thickness of approximately 0.5 mm, filled with a ceramic powder. This vessel is then heated and placed under pressure on all sides. After hot isostatic compacting the object may be readily separated from the surrounding ceramic mass and cleaned by sand blasting. This method proves to procure components with accurately shaped dimensions comparable to those of a forged product.
  • When a drill bit for rock is produced in this fashion, after sintering not the entire surface of the cutting teeth but only the parts thereof which come directly into contact with the rock are coated with the wear-resistant layer by thermal spraying. Following the selective application of the wear-resistant layer the preformed drill bit is subjected in its entirety to hot isostatic compacting, as described above.
  • The invention is now explained in greater detail by means of the accompanying drawing, which represents a preferred embodiment of the invention.
    • Fig. 1 is a cross section of a drill bit produced according to the invention.
    • Fig. 2 is a perspective view of a portion of this drill bit.
  • The drill bit 1 shown in Fig. 1 is composed of a core member 3 , made of a bearing material, in which are applied the races 2 for the folling 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 isostatically compacted cold. This operation takes place preferably under a pressure of approximately 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. 1200°C at 1 atmosphere under reduction by hydrogen for approx. I hour, which operations lead to a density of approx. 90% of the compacted material. Then, by means of plasma spraying technique, the wear-resistant layer 5 is applied on the layer 4 and the object obtained is then inserted into a vessel or container and isostatically compacted hot under a pressure of for example approx. 1600 atmospheres and at a temperature of approx. 1100°C 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 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 obtained, 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 treatment, acquires the shape, as represented in Fig. 1, in which the races 2 of the rolling elements are supplied.
  • It may be seen further from Fig. 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 where the tooth comes directly into contact with rock during operation.
  • Thus there is procured by the invention a device, such as a drill bit, which in principle consists of three parts, namely, a significantly improved 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 (10)

1. Method for producing an object on which an exterior layer is applied by thermal spraying, followed by a heat treatment, characterized in that on a core member (3) is applied, by cold isostatic compacting, a layer (4) of a suitable powder material, followed by sintering, after which the exterior layer (5), which is a wear-resistant layer, is applied and the structure thus obtained is then isostatically compacted hot.
2. Method according to claim 1, characterized in that the powder material of layer (4) is a nickel-containing alloy steel powder.
3. Method according to claim 2, characterized in that the steel powder contains 3.5% nickel.
4. Method according to claims 1-3, characterized in that after sintering of the powder material the wear-resistant layer (5) is sprayed only on the surfaces which in operation are directly subject to wearing action.
5. Method according to claims 1-4, characterized in that the core member (3) consists of a bearing material.
6. Object obtained according to the method of claims 1-5.
7. Drill bit with cutting teeth provided with a wear-resistant layer for drilling in rock, characterized in that on a core member (3) functioning as bearing is applied a layer (4) obtained by cold isostatic compacting and sintering of a suitable powder material, the cutting teeth of which are provided with theY wear-resistant layer (5) on the places where the teeth in operation come into direct contact with the rock and the preformed drill bit is isostatically compacted hot in its entirety, such that a bond is established between the layers (4) and (5), on the one hand, and between the layer (4) and core member (3), on the other.
8. Drill bit according to claim 7, characterized in that the layer (4) consists of a nickel-containing alloy steel.
9. Drill bit according to claim 7 or 8, characterized in that the nickel-containing alloy steel contains 3.5% nickel.
10. Drill bit according to claims 7-9, characterized in that the original solid core member (3) is formed by mechanical operations and heat treatment into a bearing for the bearing system of the drill bit.
EP19800201107 1979-12-04 1980-11-24 Method for producing an improved layer, particular for a drill bit Expired EP0030055B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL7908745 1979-12-04
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

Publications (2)

Publication Number Publication Date
EP0030055A1 true EP0030055A1 (en) 1981-06-10
EP0030055B1 EP0030055B1 (en) 1985-09-18

Family

ID=19834277

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19800201107 Expired EP0030055B1 (en) 1979-12-04 1980-11-24 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)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0089155A3 (en) * 1982-03-05 1983-12-07 Rolls-Royce Plc Composite articles and a method for their manufacture
FR2546448A1 (en) * 1983-05-25 1984-11-30 Maschf Augsburg Nuernberg Ag COATED METALLIC OBJECT AND METHOD FOR MANUFACTURING THE SAME
EP0169717A3 (en) * 1984-07-23 1986-12-30 Cdp, Ltd. Rolling cutters for drill bits, and processes to produce same
EP0322224A3 (en) * 1987-12-23 1990-03-07 Precision Castparts Corp. Method of forming a metal article from powdered metal
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
GB2376242A (en) * 2001-05-01 2002-12-11 Smith International Roller cone bits with wear and fracture resistant coatings
WO2002077314A3 (en) * 2001-03-26 2004-03-11 Bodycote Imt Inc Corrosion resistant component and method for fabricating same
RU2238346C1 (en) * 2003-01-20 2004-10-20 Гончаров Виталий Степанович Gaseous thermal spraying method

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4597456A (en) * 1984-07-23 1986-07-01 Cdp, Ltd. Conical cutters for drill bits, and processes to produce same
DE19747385A1 (en) * 1997-10-27 1999-04-29 Linde Ag Manufacture of molded parts

Citations (6)

* Cited by examiner, † Cited by third party
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
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

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5347307A (en) * 1976-10-13 1978-04-27 Tone Boring Co Tricone bit cone and process for production thereof

Patent Citations (8)

* Cited by examiner, † Cited by third party
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
FR2263991A1 (en) * 1974-03-13 1975-10-10 Minnesota Mining & Mfg
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
EP0005285A1 (en) * 1978-04-26 1979-11-14 SKF Industrial Trading & Development Co, B.V. Process for applying a dense layer of cermets or cemented carbides to a metal object

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0089155A3 (en) * 1982-03-05 1983-12-07 Rolls-Royce Plc Composite articles and a method for their manufacture
FR2546448A1 (en) * 1983-05-25 1984-11-30 Maschf Augsburg Nuernberg Ag COATED METALLIC OBJECT AND METHOD FOR MANUFACTURING THE SAME
EP0169717A3 (en) * 1984-07-23 1986-12-30 Cdp, Ltd. Rolling cutters for drill bits, and processes to produce same
EP0322224A3 (en) * 1987-12-23 1990-03-07 Precision Castparts Corp. Method of forming a metal article from powdered metal
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
WO2002077314A3 (en) * 2001-03-26 2004-03-11 Bodycote Imt Inc Corrosion resistant component and method for fabricating same
US6878412B2 (en) 2001-03-26 2005-04-12 Bodycote Imt, Inc. Corrosion resistant component and method for fabricating same
GB2376242A (en) * 2001-05-01 2002-12-11 Smith International Roller cone bits with wear and fracture resistant coatings
US6615935B2 (en) 2001-05-01 2003-09-09 Smith International, Inc. Roller cone bits with wear and fracture resistant surface
GB2376242B (en) * 2001-05-01 2005-11-23 Smith International Roller cone bits with wear and fracture resistant surface
RU2238346C1 (en) * 2003-01-20 2004-10-20 Гончаров Виталий Степанович Gaseous thermal spraying method

Also Published As

Publication number Publication date
JPS6343550B2 (en) 1988-08-31
CA1162182A (en) 1984-02-14
DE3071100D1 (en) 1985-10-24
AU539718B2 (en) 1984-10-11
JPS5697093A (en) 1981-08-05
AU6438680A (en) 1981-06-11
NL7908745A (en) 1981-07-01
EP0030055B1 (en) 1985-09-18

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