GB2273301A - Improved gage protection for rock bits - Google Patents
Improved gage protection for rock bits Download PDFInfo
- Publication number
- GB2273301A GB2273301A GB9321726A GB9321726A GB2273301A GB 2273301 A GB2273301 A GB 2273301A GB 9321726 A GB9321726 A GB 9321726A GB 9321726 A GB9321726 A GB 9321726A GB 2273301 A GB2273301 A GB 2273301A
- Authority
- GB
- United Kingdom
- Prior art keywords
- carbide
- insert
- rock bit
- gage
- set forth
- 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
Links
- 239000011435 rock Substances 0.000 title claims abstract description 42
- UONOETXJSWQNOL-UHFFFAOYSA-N tungsten carbide Chemical compound [W+]#[C-] UONOETXJSWQNOL-UHFFFAOYSA-N 0.000 claims abstract description 26
- 239000000843 powder Substances 0.000 claims abstract description 16
- 239000010941 cobalt Substances 0.000 claims abstract description 15
- 229910017052 cobalt Inorganic materials 0.000 claims abstract description 15
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims abstract description 15
- 229910052742 iron Inorganic materials 0.000 claims abstract description 7
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 7
- 229910052751 metal Inorganic materials 0.000 claims description 18
- 239000002184 metal Substances 0.000 claims description 18
- 239000011230 binding agent Substances 0.000 claims description 15
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 12
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 12
- 238000012423 maintenance Methods 0.000 claims description 7
- 239000000956 alloy Substances 0.000 claims description 3
- 229910045601 alloy Inorganic materials 0.000 claims description 3
- 230000000737 periodic effect Effects 0.000 claims description 3
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 3
- 229910052721 tungsten Inorganic materials 0.000 claims description 3
- 239000010937 tungsten Substances 0.000 claims description 3
- 239000002245 particle Substances 0.000 claims 8
- 230000002708 enhancing effect Effects 0.000 claims 2
- 238000000034 method Methods 0.000 claims 2
- 238000005245 sintering Methods 0.000 claims 2
- 239000011882 ultra-fine particle Substances 0.000 claims 2
- 238000005553 drilling Methods 0.000 abstract description 14
- 230000006835 compression Effects 0.000 abstract description 4
- 238000007906 compression Methods 0.000 abstract description 4
- 229910003460 diamond Inorganic materials 0.000 description 4
- 239000010432 diamond Substances 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 3
- 238000005755 formation reaction Methods 0.000 description 3
- 239000000314 lubricant Substances 0.000 description 3
- 239000012530 fluid Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- INZDTEICWPZYJM-UHFFFAOYSA-N 1-(chloromethyl)-4-[4-(chloromethyl)phenyl]benzene Chemical compound C1=CC(CCl)=CC=C1C1=CC=C(CCl)C=C1 INZDTEICWPZYJM-UHFFFAOYSA-N 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 239000000356 contaminant Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000003966 growth inhibitor Substances 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000002028 premature Effects 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C29/00—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides
- C22C29/02—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides
- C22C29/06—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides based on carbides, but not containing other metal compounds
- C22C29/08—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides based on carbides, but not containing other metal compounds based on tungsten carbide
-
- 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)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Mining & Mineral Resources (AREA)
- Materials Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Fluid Mechanics (AREA)
- Geochemistry & Mineralogy (AREA)
- Environmental & Geological Engineering (AREA)
- Composite Materials (AREA)
- Manufacturing & Machinery (AREA)
- Physics & Mathematics (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Earth Drilling (AREA)
Abstract
A rotary cone drill bit is disclosed as having ultra hard gage maintaining cemented tungsten carbide inserts which are formed from tungsten carbide powder having an average grain size of less than 1.0 micron, preferably in the range of from 0.05 to 0.5 microns cemented with Co, Ni or Fe. Preferably, the carbide is cemented with less than 16 weight percent cobalt. Such inserts have a hardness from 92.5 Rockwell A to 97.0 Rockwell A as compared with less than 92 Rockwell A for previous inserts. These heel row inserts significantly increase the wear resistance of the bit gage surfaces. When used in compression on the gage heel row these inserts will withstand the high impact loads encountered in hard tough rock bit drilling. <IMAGE>
Description
IMPROVED GAGE PROTECTION FOR ROCK BITS
The present invention relates to rotary cone rock bits having hard metal cutter inserts positioned on the rotary cones of a rock bit.
More specifically, this invention relates to very hard, wear resistant cemented tungsten carbide inserts fitted particularly on the heel surface of a rotary cone for a rock bit. The heel surface of a cone for a roller cone bit, on which the tungsten carbide inserts are positioned is the only surface on the roller cone that is essentially perpendicular to the borehole bottom and parallel to the bit centerline at the moment of rolling contact of the heel surface with the borehole wall. In the drilling industry, maintenance of the gage circumference of a borehole is essential to prevent pinching of subsequent rock bits as they are lowered into the borehole for continued drilling. If the heel row of inserts of a roller bit becomes worn, the rock bit begins to drill an undersize borehole.Replacement of a worn rock bit with a new bit having a gage diameter that is larger than the gage of the borehole cut by the previous undersize rock bit means that the bit engages the wall of the borehole before it reaches the bottom. Consequently, as the new bit is lowered into the formation it becomes pinched, resulting in either catastrophic failure of the rock bit or drastically reduced rock bit life.
It is well known in the art to provide hard, wear resistant gage protection on the heel rows of the roller cones of a rock bit. For example, U.S. Patent
No. 3,727,705 describes cylindrical tungsten carbide inserts positioned on the gage heel row of a roller bit. This patent shows using standard hard ( < 92
Rockwell A) carbide heel row inserts positioned at different spacings and diameters on the heel row surface of each roller cone of the drill bit. This provides more dense and broader contact area of the inserts in contact with an abrasive earthen formation wall while drilling. Although this does provide somewhat better gage wear protection, it still has insufficient wear resistance to maintain bit gage diameter when drilling many very hard and abrasive rocks.
U.S. Patent No. 4,940,099 shows using normal hard grade ( < 92 Rockwell A) tungsten carbide heel row inserts alternating with softer grade tungsten carbide inserts having polycrystalline diamond (PDC) outer wear surfaces. While this arrangement does improve wear resistance of the bit gage surfaces in some applications, PDC insert breakage is still a serious problem because of the high impact loads encountered while drilling extremely hard and tough rock.
Polycrystalline diamond is extremely hard but very brittle. Its impact strength is an inverse function of its hardness.
It would be desirable to mitigate premature wear and/or breakage of the gage maintaining heel row cemented carbide inserts of a roller cone rock bit, thereby assuring a full gage well bore.
There is therefore provided in practice of this invention a carbide insert for use in a gage maintenance row of a rock bit comprising a cemented tungsten carbide powder with an average grain size of less than 1.0 micron. Preferably, this powder has a size range from 0.05 micron to 0.5 micron and a metal binder selected from the group consisting of cobalt, nickel and iron.
The present invention is one relating to rotary drill bits in which tungsten carbide cutting inserts are rigidly affixed in sockets in rotatable cones.
Further, a group of inserts in each cone define a heel or gage reaming row. These heel row inserts are made of cemented tungsten carbide having hardness ranging from 92.5 Rockwell A to 97.0 Rockwell A, which is significantly harder than inserts in present use, therefore making them superior for gage wear maintenance of a rock bit roller cone gage surface.
These heel row tungsten carbide inserts also have the toughness to withstand the high drilling impact loads that often fracture the prior art polycrystalline diamond compact heel row inserts.
These and additional features and advantages of this invention will become more fully apparent in the following description when considered in conjunction with the accompanying drawings wherein:
FIGURE 1 is a perspective view showing a roller cutter drill bit that embodies the principles of the invention; and
FIGURE 2 is fragmentary view in longitudinal section of roller cutter drill bit having a rotatable cutter cone supported thereon.
Figure 1 illustrates a rotary cone rock bit 10 fitted with tungsten carbide cutting inserts generally designated as 20. The bit consists of a bit body 12 threaded at a pin end 14 and having a cutting end generally designated as 16. Each leg 13 on the bit body supports a rotary cone 18 rotatably retained on a journal 25 cantilevered from each of the legs (Fig. 2).
The tungsten carbide drilling inserts 20 are, for example, rigidly affixed in circumferential rows on each of the rotary cones. Typically, these inserts as well as the heel row inserts 22 are press fitted under compression into insert retention sockets formed in the cones. The heel row gage reaming inserts 22 are rigidly mounted on the outer gage surface 21 of each rotary cone 18. The heel row inserts are essentially flush with the gage surface 21 of the rock bit roller cone 18.
The rock bit 10 further includes a drilling fluid passage through the pin end 14 that communicates with a plenum chamber (not shown) inside the body.
Typically one or more nozzles 15 are secured within bit body 12. The nozzles 15 direct drilling fluid from the plenum toward a borehole bottom. The upper portion of each of the legs 13 may have a lubricant reservoir 19 to supply a lubricant to each of the rotary cones 18.
As shown in Figure 2, each rotary cone head section 18 has ball bearings 24 positioned in a raceway 23 to rotatably affix the cone 18 to the journal 25.
Further bearing means are provided, such as the main journal bearing 26, the journal nose thrust button 27 and the journal thrust washer 28. Sealing means, such as an O-ring 29, are used to retain lubricant in the bearings and to exclude contaminants.
A plurality of tungsten carbide drilling inserts 20 are rigidly affixed in circumferential rows on each rotary cone 18. The gage maintaining heel row inserts 22 are rigidly mounted in compression and are normal to and essentially flush with the gage surface 21 to provide gage wear protection and to maintain a full gage well bore.
New technology has now made possible the manufacture and use of tungsten carbide (WC) powders considerably smaller than 1.0 micron, having a size range of 0.05 micron to 0.5 micron. This is many times smaller than the greater than one micron powders currently used in the hardest grade (90.0 Rockwell A to 92.5 Rockwell A) cemented carbide inserts for rock bit gage protection. Using these new ultra fine grained WC powders with appropriate grain growth inhibitors (such as vanadium carbide), and an appropriate binder such as cobalt (less than 16% by weight), ultra hard (92.5
Rockwell A to 97.0 Rockwell A) cemented tungsten carbide inserts can commercially be made. Although tungsten is the preferred carbide former for use in this invention, carbides of all the metals in Group IV
A, V A, and VI A of the periodic system, or an alloy thereof, can theoretically be used for this purpose.
Also cobalt is the preferred binder metal for use in this invention, but nickel and iron can be used advantageously.
The carbide heel row inserts 22, described above, have the toughness to withstand high impact drilling conditions when used in compression of a press fit heretofore described.
It should be apparent from the foregoing description that the present invention provides significant advantages. When drilling very tough abrasive rock formations these novel carbide gage reaming inserts 22 have the hardness to provide significantly better gage wear protection for a rock bit than do state of the art tungsten carbide gage inserts; thereby greatly extending the useful life of the bit. Under very high impact drilling conditions this invention can withstand much higher impact loads without breakage than do polycrystalline diamond compacts. This also significantly extends the useful life of the bit.
It will of course be realized that various modifications can be made in the design and materials of the present invention without departing from the spirit thereof. Thus while the principal preferred construction and materials of the invention have been explained and illustrated in what is now considered to represent its best embodiments, it should be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.
Claims (13)
1. A rotary cone rock bit comprising:
a bit body;
at least one rotary cutter cone mounted for rotation on the bit body;
a plurality of cemented carbide cutting inserts mounted in the cutter cone; and
a plurality of cemented carbide gage inserts in a gage maintenance row on the cutter cone, such a gage insert comprising a carbide powder with an average grain size of less than 1.0 micron and a metal binder selected from the group consisting of cobalt, iron and nickel, said gage insert having a hardness in the range of from 92.5 Rockwell A to 97.0 Rockwell A.
2. The rotary cone rock bit as set forth in
Claim 1 wherein said carbide powder is formed from a metal selected from Groups IV A, V A, VI A of the periodic system or an alloy thereof.
3. The rotary cone rock bit as set forth in either one of Claims 1 or 2 wherein the carbide powder is formed from tungsten.
4. The rotary cone rock bit as set forth in any of the preceding claims wherein the metal binder is cobalt.
5. The rotary cone rock bit as set forth in any of the preceding claims wherein the cobalt content is less than 16 percent by weight.
6. The rotary cone rock bit as set forth in any of the preceding claims wherein the particle size of the carbide is in the range of from 0.05 to 0.5 microns.
7. A method of enhancing the wear resistance and toughness of sintered cemented carbide inserts comprising the steps of;
compacting ultra fine tungsten carbide particles having an average grain size of less than 1.0 micron,
cementing said ultra fine particles with a cobalt metal binder, and
sintering said carbide particles and said metal binder into suitable insert shapes.
8. A cemented tungsten carbide insert for use in a gage maintenance row of a rock bit comprising tungsten carbide powder with an average grain size of less than 1.0 micron and a metal binder of cobalt being less than 16 percent content by weight.
9. The insert as set forth in Claim 8 wherein the carbide insert has a hardness from 92.5 Rockwell A to 97.0 Rockwell A.
10. The insert as set forth in Claim either one of Claims 8 or 9 wherein the particle size of the carbide is in the range of from 0.05 to 0.5 microns.
11. A cemented carbide insert for use in a rock bit comprising carbide powder with an average grain size of less than 1.0 micron and a metal binder selected from the group consisting of cobalt, iron and nickel.
12. A rock bit substantially as described herein with reference to the accompanying drawings.
13. An insert for use in a rock bit substantially as described herein with reference to the accompanying drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US97956192A | 1992-11-20 | 1992-11-20 |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB9321726D0 GB9321726D0 (en) | 1993-12-15 |
| GB2273301A true GB2273301A (en) | 1994-06-15 |
| GB2273301B GB2273301B (en) | 1996-10-30 |
Family
ID=25526963
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9321726A Expired - Fee Related GB2273301B (en) | 1992-11-20 | 1993-10-21 | Improved cage protection for rock bits |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2273301B (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1999010552A1 (en) * | 1997-08-27 | 1999-03-04 | Kennametal Inc. | A ROTARY EARTH STRATA PENETRATING TOOL WITH A CERMET INSERT HAVING A Co-Ni-Fe-BINDER |
| US6010283A (en) * | 1997-08-27 | 2000-01-04 | Kennametal Inc. | Cutting insert of a cermet having a Co-Ni-Fe-binder |
| US6022175A (en) * | 1997-08-27 | 2000-02-08 | Kennametal Inc. | Elongate rotary tool comprising a cermet having a Co-Ni-Fe binder |
| US6024776A (en) * | 1997-08-27 | 2000-02-15 | Kennametal Inc. | Cermet having a binder with improved plasticity |
| US6170917B1 (en) | 1997-08-27 | 2001-01-09 | Kennametal Inc. | Pick-style tool with a cermet insert having a Co-Ni-Fe-binder |
| US8323372B1 (en) * | 2000-01-31 | 2012-12-04 | Smith International, Inc. | Low coefficient of thermal expansion cermet compositions |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1266966A (en) * | 1968-05-15 | 1972-03-15 | ||
| GB1450654A (en) * | 1973-01-26 | 1976-09-22 | Gen Electric | Abrasion resistant cemented carbide |
| US4950328A (en) * | 1988-07-12 | 1990-08-21 | Mitsubishi Metal Corporation | End mill formed of tungsten carbide-base sintered hard alloy |
| US5009705A (en) * | 1989-12-28 | 1991-04-23 | Mitsubishi Metal Corporation | Microdrill bit |
-
1993
- 1993-10-21 GB GB9321726A patent/GB2273301B/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1266966A (en) * | 1968-05-15 | 1972-03-15 | ||
| GB1450654A (en) * | 1973-01-26 | 1976-09-22 | Gen Electric | Abrasion resistant cemented carbide |
| US4950328A (en) * | 1988-07-12 | 1990-08-21 | Mitsubishi Metal Corporation | End mill formed of tungsten carbide-base sintered hard alloy |
| US5009705A (en) * | 1989-12-28 | 1991-04-23 | Mitsubishi Metal Corporation | Microdrill bit |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1999010552A1 (en) * | 1997-08-27 | 1999-03-04 | Kennametal Inc. | A ROTARY EARTH STRATA PENETRATING TOOL WITH A CERMET INSERT HAVING A Co-Ni-Fe-BINDER |
| US5992546A (en) * | 1997-08-27 | 1999-11-30 | Kennametal Inc. | Rotary earth strata penetrating tool with a cermet insert having a co-ni-fe-binder |
| US6010283A (en) * | 1997-08-27 | 2000-01-04 | Kennametal Inc. | Cutting insert of a cermet having a Co-Ni-Fe-binder |
| US6022175A (en) * | 1997-08-27 | 2000-02-08 | Kennametal Inc. | Elongate rotary tool comprising a cermet having a Co-Ni-Fe binder |
| US6024776A (en) * | 1997-08-27 | 2000-02-15 | Kennametal Inc. | Cermet having a binder with improved plasticity |
| US6170917B1 (en) | 1997-08-27 | 2001-01-09 | Kennametal Inc. | Pick-style tool with a cermet insert having a Co-Ni-Fe-binder |
| US8323372B1 (en) * | 2000-01-31 | 2012-12-04 | Smith International, Inc. | Low coefficient of thermal expansion cermet compositions |
| US8956438B2 (en) | 2000-01-31 | 2015-02-17 | Smith International, Inc. | Low coefficient of thermal expansion cermet compositions |
Also Published As
| Publication number | Publication date |
|---|---|
| GB9321726D0 (en) | 1993-12-15 |
| GB2273301B (en) | 1996-10-30 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20111021 |