Mining or in situ disintegration of hard material – Cutter tooth or tooth head – Wear resistant feature for tool body
Reexamination Certificate
1997-08-27
2001-01-09
Lillis, Eileen D. (Department: 3673)
Mining or in situ disintegration of hard material
Cutter tooth or tooth head
Wear resistant feature for tool body
C299S108000, C299S110000, C075S240000, C051S309000, C428S698000
Reexamination Certificate
active
06170917
ABSTRACT:
BACKGROUND
The present invention pertains to a pick-style tool such as, for example, a road planing tool or a point attack mine tool or an open-face longwall tool, which has a hard insert at the axially forward end. Such pick-style tools have been typically used to penetrate the earth strata or other substrates (e.g., asphalt roadway surfaces) wherein the pick-style tool is carried, either in a rotatable or a non-rotatable fashion, by a drive member (e.g., drum or chain).
The typical pick-style tool has a hard insert affixed at the axially forward end. The hard insert is the part of the pick-style tool that first impinges upon the earth strata or other substrate. The hard insert is comprised of a tungsten carbide cermet (WC-cermet), also known as cobalt cemented tungsten carbide and WC—Co. Here, a cobalt binder (Co-binder) cements tungsten carbide particles together. Although hard inserts made of a WC-cermet having a Co-binder have achieved successful results, there are some drawbacks.
One drawback is that up to about 45 percent of the world's primary cobalt production is located in politically unstable regions (e.g., political regions that have experienced either armed or peaceful revolutions in the past decade and could still experience additional revolutions). About 15 percent of the world's annual primary cobalt market is used in the manufacture of hard materials including WC-cermets. About 26 percent of the world's annual primary cobalt market is used in the manufacture of superalloys developed for advanced aircraft turbine engines—a factor contributing to cobalt being designated a strategic material. These factors not only contribute to the high cost of cobalt but also explain cobalt's erratic cost fluctuations. Consequently, cobalt has been relatively expensive, which, in turn, has raised the cost of the WC-cermet hard insert, as well as the cost of the overall pick-style tool. Such an increase in the cost of the pick-style tool has been an undesirable consequence of the use of the Co-binder for the hard insert. Therefore, it would be desirable to reduce cobalt from the binder of WC-cermet hard inserts.
Furthermore, because of the principal locations of the largest cobalt reserves, there remains the potential that the supply of cobalt could be interrupted due to any one of a number of causes. The unavailability of cobalt would, of course, be an undesirable occurrence.
Pick-style tools operate in environments that are corrosive. While the WC-cermet hard inserts have been adequate in such environments, there remains the objective to develop a hard insert which has improved corrosion resistance while maintaining essentially the same wear characteristics of WC-cermet hard inserts.
While the use of WC-cermet hard inserts have been successful, there remains a need to provide a hard insert that does not have the drawbacks, i.e., cost and the potential for unavailability, inherent with the use of cobalt set forth above. There also remains a need to develop a hard insert for use in corrosive environments which possess improved corrosion resistance while maintaining essentially the same wear characteristics of WC-cermets having a Co-binder.
SUMMARY
In one embodiment, the invention is a pick-style tool which comprises an elongate tool body that has an axially forward end and an axially rearward end. A hard insert is affixed to the tool body at the axially forward end. The composition of the hard insert comprises about 5 weight percent (wt. %) to about 27 wt. % binder, and about 73 wt. % to about 95 wt. % tungsten carbide (WC). The binder comprises a cobalt-nickel-iron-binder (Co—Ni—Fe-binder).
In another embodiment, the invention is a hard insert for use in a pick-style tool having an elongate tool body with an axially forward end. The hard insert is affixed to the tool body at the axially forward end. The composition of the hard insert comprises about 5 wt. % to about 27 wt. % binder, and about 73 wt. % to about 95 wt. % tungsten carbide (WC). The binder comprises a Co—Ni—Fe-binder.
In still another embodiment, the invention is a rotatable cutting tool comprising an elongate tool body that has an axially forward end with a hard insert affixed to the tool body at the axially forward end. The composition of the hard insert about 5 wt. % to about 27 wt. % binder. The binder comprises at least about 40 wt. % cobalt but not more than about 90 wt. % cobalt, at least about 4 wt. % nickel, and at least about 4 wt. % iron. The tungsten carbide has a grain size of about 1 micrometer (&mgr;m) to about 30 &mgr;m.
The invention illustratively disclosed herein may suitably be practiced in the absence of any element, step, component, or ingredient that is not specifically disclosed herein.
REFERENCES:
patent: Re. 30807 (1981-12-01), Elders
patent: Re. 34180 (1993-02-01), Nemeth et al.
patent: 2162574 (1939-06-01), Dawihl et al.
patent: 2202821 (1940-06-01), Balke
patent: 3514271 (1970-05-01), Yates
patent: 3816081 (1974-06-01), Hale
patent: 4049380 (1977-09-01), Yih et al.
patent: 4083605 (1978-04-01), College et al.
patent: 4556424 (1985-12-01), Viswanadham
patent: 4593776 (1986-06-01), Salesky et al.
patent: 4642003 (1987-02-01), Yoshimura
patent: 4743515 (1988-05-01), Fisher et al.
patent: 4869329 (1989-09-01), Kar et al.
patent: 4907665 (1990-03-01), Kar et al.
patent: 4971485 (1990-11-01), Nomura et al.
patent: 5066553 (1991-11-01), Yoshimura et al.
patent: 5186739 (1993-02-01), Isobe et al.
patent: 5219209 (1993-06-01), Prizzi et al.
patent: 5541006 (1996-07-01), Conley
patent: 5658395 (1997-08-01), Wahlberg et al.
patent: 5697042 (1997-12-01), Massa et al.
patent: 5716170 (1998-02-01), Kammermeier et al.
patent: 5766742 (1998-06-01), Nakamura et al.
patent: 5776588 (1998-07-01), Moriguchi et al.
patent: 5776593 (1998-07-01), Massa et al.
patent: 5806934 (1998-09-01), Massa et al.
patent: 5821441 (1998-10-01), Kawamura
patent: 6024776 (2000-02-01), Heinrich et al.
patent: 29617040 (1997-03-01), None
patent: 1543214 (1968-10-01), None
patent: 2273301 (1994-06-01), None
patent: 46-15204 (1971-04-01), None
patent: 50-110909 (1975-09-01), None
patent: 53-21016 (1978-02-01), None
patent: 54-29900 (1979-03-01), None
patent: 61-194147 (1986-08-01), None
patent: WO9621052 (1996-07-01), None
patent: 9721844 (1997-06-01), None
U.S. application No. 08/918993, Heinrich et al., filed Aug. 27, 1997.
U.S. application No. 08/918982, Heinrich et al., filed Aug. 27, 1997.
U.S. application No. 08/921996, Heinrich et al., filed Aug. 27, 1997.
Grewe et al.: “Substitution of cobalt in Cemented Carbides,” Metall (Berlin (1986) 40(2), 133-140, XP002086162 [Translation].
L. J. Prakash et al.: “The influence of the Binder Composition on the Properties of WC—Fe/Co/Ni Cemented Carbides,” Mod. Dev. Powder Metal, vol. 14, 1981, XP002085832.
Chemical Abstracts, vol. 121, No. 22, Nov. 1994, Abstract No. 261210. (J. M. Guilemany et al.: “Mechanical-Property Relationships of Co/WC and Co—Ni—Fe/WC Hard Metal Alloys,” Int. J. Refractory Metals & Hard Materials, (1994), 12(4), 199-206).
B. Uhrenius et al.: “On the Composition of Fe—Ni—Co—WC-based Cemented Carbides,” vol. 15, 1997, pp. 139-149, XP002085833.
H. Grewe et al.: “Substitution of Cobalt in Cemented Carbides,” Metall (Berlin) (1986), 40)2), 133-40, XP002086162.
Chemical Abstracts, vol. 126, No. 9, Mar. 1997, Abstract No. 121055. (Yoshihiro Minato et al.: “Tungsten Carbide-Based Hard Alloys Having High Impact Resistance for Tools,” JP 08 302441 A (Sumitomo Electric Industries, Japan)).
Chemical Abstracts, vol. 114, No. 6, Feb. 1991, Abstract No. 47911. (Noribumi Kikichi et al.: “Manufacture of Surface-Coated Tungsten Carbide-Based Cermets for Cutting Tools,” JP02 022454 (Mitsubishi Metal Corp., Japan)).
Chemical Abstracts, vol. 108, No. 12, Mar. 1988, Abstract No. 99568. (Sokichi Taktau et al.: “Alumina-Coated (Mitsubishi Metal Corp., Japan) Sintered Alloys for Cutting Tools,” JP 62 047123 (Toshiba Tungaloy Co., Ltd, Japan)).
Copies of International Search Reports mailed Dec. 14, 1998, in Application Nos. PCT/IB98/01297, PCT/IB98/0129
Heinrich Hans-Wilm
Schleinkofer Uwe
Schmidt Dieter
Wolf Manfred
Kennametal Inc.
Kreck John
Lillis Eileen D.
Prizzi John J.
LandOfFree
Pick-style tool with a cermet insert having a Co-Ni-Fe-binder does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Pick-style tool with a cermet insert having a Co-Ni-Fe-binder, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pick-style tool with a cermet insert having a Co-Ni-Fe-binder will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2482514