Braze alloy

Abstract

A braze alloy is described which includes indium and / or thallium as alloying elements. For example, between about 0.5% and about 10% by weight of indium (In) and / or thallium (Tl) can be added to a braze alloy to reduce the braze temperature without substantially effecting braze strength. Braze alloys that are alloyed to including indium (In) and / or thallium (Tl) can be use in brazing cutting elements to drilling tools. These alloying elements may also be added to braze alloys used for other applications to reduce braze temperature.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit under 35 U.S.C. §120 as a continuation of U.S. application Ser. No. 10 / 692,926, filed Oct. 24, 2003, titled “Improved Braze Alloy for Drilling Applications,” and incorporated by reference.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT [0002] Not applicable. BACKGROUND OF INVENTION [0003] 1. Field of the Invention [0004] The present invention relates to a braze alloy. More particularly, the present invention relates to a braze alloy having alloying elements added to reduce braze temperature. [0005] 2. Background Art [0006] Earth boring tools, and in particular drill bits, are commonly used in the oil and gas industry for drilling well bores. FIG. 1 shows one example of a conventional drilling system for drilling through earth formation. The drilling system includes a drilling rig 1 used to turn a drill string 2 which extends downward into a well bore 4. Connected to the end of the dril...

AI Technical Summary

Benefits of technology

[0013] The present invention provides a braze alloy that includes indium and/or thallium. In one aspect, a braze alloy comprises at least about 0.5% to about 10% by weight of at least one selected from the group of indium (In) and thallium (Ti). In one or more em

Problems solved by technology

This temperature restriction greatly limits the number of alloys that can be used as braze alloy for cutting elements with ultrahard material because most brazing alloys that provide sufficient shear strength for bonding cutting elements to a drill bit also require brazing at temperatures above 1350° F. Therefore, alloys suitable for brazing cutting elements with ultrahard material thereon have been limited to only a couple of alloys which offer low enough brazing temperatures to avoid damage to the ultrahard layer and high enough braze strength to retain cutting elements on drill bits.

Brazing at high temperatures, such as around 1350° F. has also been found to result in a build up of residual stresses in the ultrahard material which can increase the chances of cutting elements cracking and chipping during drilling.

As a result, cutters brazed at higher temperatures typically have a higher chance of cracking and chipping in the field because of the higher stresses developed due to exposure to brazing temperatures.

This is a primary reason for cutting element loss, which can result in over loading of adjacent cutting elements which can lead to premature failure of the bit.

Additionally, when a cutting element falls out of its support structure on the bit, the fallen cutting element may get jammed against the bit, causing further bit damage and accelerating the premature failure of the bit.

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