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AssigneeSmith International, Inc.
InventorsKumar T. Kembaiyan, Thomas W. Oldham, John (Youhe) Zhang
Estimating the term…
Drill bit reinforcing members or blanks of this invention are formed from high-strength steels having a carbon content less than about 0.3 percent by weight, a yield strength of at least 55,000 psi, a tensile strength of at least 80,000 psi, a toughness of at least 40 CVN-L, Ft-lb, and a rate of expansion percentage change less than about 0.0025%/° F. during austenitic to ferritic phase transformation. In one embodiment, such steel comprises in the range of from about 0.1 to 0.3 percent by weight carbon, 0.5 to 1.5 percent by weight manganese, up to about 0.8 percent by weight chromium, 0.05 to 4 percent by weight nickel, and 0.02 to 0.8 percent by weight molybdenum. In another example, such steel comprises in the range of from about 0.1 to 0.3 percent by weight carbon, 0.9 to 1.5 percent by weight manganese, 0.1 to 0.5 percent by weight silicon, and one or more microalloying element selected from the group consisting of vanadium, niobium, titanium, zirconium, aluminum and mixtures thereof.
A reinforcing member disposed within an earth-boring drill bit formed from a high-strength steel having a carbon content less than about 0.3 percent by weight, having a chromium content of up to about 0.8 percent by weight, and having a yield strength of at least 55,000 psi, a tensile strength of at least 80,000 psi, and a toughness of at least 40 CVN-L, Ft-lb.
An earth-boring drill bit comprising:
An earth-boring drill bit comprising:
Dependencies are inferred from the claim text.