EP0288775A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Earth working tool having a working element fabricated from cemented tungsten carbide compositions with enhanced properties
Assignee: Kennametal Inc
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Filing: 1988-03-31
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Granted: —
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Expires: 2008-03-31
Abstract
Abstract An earth working tool, such as a mining and construction cutter bit, has an elongated body, and a working element, such as a hard tip attached on a forward end of the body. The working element or hard tip is fabricated of a composition of essentially tungsten carbide of large grain size. The composition has one of a plurality of different percents, X, by weight of cobalt as a binder and one of a plurality of different Rockwell A scale hardnesses, Y. The cobalt percents X and hardnesses Y are paired in sets and have nominal values which satisfy the relationship: Y = 91 - 0.62X, where X is selected from within a range of from about 4.5 to 11.5 percent. Also, the values of Y in the sets of X and Y have upper and lower limits which satisfy the respective relationships: Y = 91.1 - 0.57X and Y = 90.9 - 0.67X, where X is selected from the aforementioned range of from about 4.5 to 11.5 percent. More particularly, each composition has one set of cobalt percent X and hardness Y values selected from a plurality of different sets of (X, Y) as follows: (4.5 +/- 0.3, 88.2 +/- 0.3), (5.0 +/- 0.3, 87.9 +/- 0.3), (8.5 +/- 0.5, 85.8 +/- 0.5) and (10.5 +/- 0.5, 84.5 +/- 0.6).
Inventors
- 👤 Mark S. Greenfield
- 👤 Edward V. Conley
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 06:28
CPC Classifications
C; C22; C22C; C22C29/00; C22C29/02; C22C29/06; C22C29/08; E; E21; E21C; E21C35/00; E21C35/18; E21C35/183; E21C35/1835; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12014; Y10T428/12028; Y10T428/12049; Y10T428/12056; Y10T428/12063; Y10T428/12139
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
106 words
An earth working tool, comprising: (a) an elongated body; and (b) a working element attached on a forward end of said body and being fabricated of a composition of essentially tungsten carbide of large grain size, said composition having one of a plurality of different percents, X, by weight of cobalt as a binder and one of a plurality of different Rockwell A scale hardnesses, Y, wherein said cobalt percents X and hardnesses Y are paired in sets and have nominal values which satisfy the relationship: Y = 91 - 0.62X, where X is selected from within a range of from about 4.5 to 11.5 percent.
Claim 2
Dependent Claim
106 words
An earth working tool, comprising: (a) an elongated body; and (b) a working element attached on a forward end of said body and being fabricated of a composition of essentially tungsten carbide of large grain size, said composition having one of a plurality of different percents, X, by weight of cobalt as a binder and one of a plurality of different Rockwell A scale hardnesses, Y, wherein said cobalt percents X and hardnesses Y are paired in sets and have nominal values which satisfy the relationship: Y = 91 - 0.62X, where X is selected from within a range of from about 4.5 to 11.5 percent.
Claim 3
Dependent Claim
46 words
The working tool as recited in Claim 1, wherein the values of Y in said sets of X and Y have upper limits which satisfy the relationship: Y = 91.1 - 0.57X, where X is selected from said range of from about 4.5 to 11.5 percent.
Claim 4
Dependent Claim
46 words
The working tool as recited in Claim 1, wherein said values of Y in said sets of X and Y have lower limits which satisfy the relationship: Y = 90.9 - 0.67X, where X is selected from said range of from about 4.5 to 11.5 percent.
Claim 5
Dependent Claim
60 words
An earth working tool, comprising: (a) an elongated body; and (b) a working element attached on a forward end of said body and being fabricated of a composition of essentially tungsten carbide of large grain size, said composition having 4.5 +/- 0.3 percent by weight of cobalt as a binder and a Rockwell A scale hardness of 88.2 +/- 0.3.
Claim 6
Dependent Claim
60 words
An earth working tool, comprising: (a) an elongated body; and (b) a working element attached on a forward end of said body and being fabricated of a composition of essentially tungsten carbide of large grain size, said composition having 4.5 +/- 0.3 percent by weight of cobalt as a binder and a Rockwell A scale hardness of 88.2 +/- 0.3.
Claim 7
Dependent Claim
60 words
An earth working tool, comprising: (a) an elongated body; and (b) a working element attached on a forward end of said body and being fabricated of a composition of essentially tungsten carbide of large grain size, said composition having 5.0 +/- 0.3 percent by weight of cobalt as a binder and a Rockwell A scale hardness of 87.9 +/- 0.3.
Claim 8
Dependent Claim
60 words
An earth working tool, comprising: (a) an elongated body; and (b) a working element attached on a forward end of said body and being fabricated of a composition of essentially tungsten carbide of large grain size, said composition having 5.0 +/- 0.3 percent by weight of cobalt as a binder and a Rockwell A scale hardness of 87.9 +/- 0.3.
Claim 9
Dependent Claim
60 words
An earth working tool, comprising: (a) an elongated body; and (b) a working element attached on a forward end of said body and being fabricated of a composition of essentially tungsten carbide of large grain size, said composition having 8.5 +/- 0.5 percent by weight of cobalt as a binder and a Rockwell A scale hardness of 85.8 +/- 0.5.
Claim 10
Dependent Claim
60 words
An earth working tool, comprising: (a) an elongated body; and (b) a working element attached on a forward end of said body and being fabricated of a composition of essentially tungsten carbide of large grain size, said composition having 8.5 +/- 0.5 percent by weight of cobalt as a binder and a Rockwell A scale hardness of 85.8 +/- 0.5.
Claim 11
Dependent Claim
60 words
An earth working tool, comprising: (a) an elongated body; and (b) a working element attached on a forward end of said body and being fabricated of a composition of essentially tungsten carbide of large grain size, said composition having 10.5 +/- 0.5 percent by weight of cobalt as a binder and a Rockwell A scale hardness of 84.5 +/- 0.6.
Claim 12
Dependent Claim
60 words
An earth working tool, comprising: (a) an elongated body; and (b) a working element attached on a forward end of said body and being fabricated of a composition of essentially tungsten carbide of large grain size, said composition having 10.5 +/- 0.5 percent by weight of cobalt as a binder and a Rockwell A scale hardness of 84.5 +/- 0.6.
Claim 13
Dependent Claim
107 words
An earth working tool, comprising: (a) an elongated body; and (b) a working element attached on a forward end of said body and being fabricated of a composition of essentially tungsten carbide of large grain size, said composition having one of a plurality of different percents, X, by weight of cobalt as a binder and one of a plurality of different Rockwell A scale hardnesses, Y, wherein said cobalt percents X and hardnesses Y are paired in sets, (X, Y), as follows: (4.5 +/- 0.3, 88.2 +/- 0.3), (5.0 +/- 0.3, 87.9 +/- 0.3), (8.5 +/- 0.5, 85.8 +/- 0.5) and (10.5 +/- 0.5, 84.5 +/- 0.6).
Claim 14
Dependent Claim
107 words
An earth working tool, comprising: (a) an elongated body; and (b) a working element attached on a forward end of said body and being fabricated of a composition of essentially tungsten carbide of large grain size, said composition having one of a plurality of different percents, X, by weight of cobalt as a binder and one of a plurality of different Rockwell A scale hardnesses, Y, wherein said cobalt percents X and hardnesses Y are paired in sets, (X, Y), as follows: (4.5 +/- 0.3, 88.2 +/- 0.3), (5.0 +/- 0.3, 87.9 +/- 0.3), (8.5 +/- 0.5, 85.8 +/- 0.5) and (10.5 +/- 0.5, 84.5 +/- 0.6).
References Cited (Backward Citations)
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