Patent 7871133 was granted and assigned to Schlumberger on January, 2011 by the United States Patent and Trademark Office.
In one aspect of the invention, a degradation assembly comprises an impact tip brazed to a carbide bolster. A stem protrudes from the bolster, being adapted to be retained within a bore connected to a driving mechanism. A locking fixture is disposed within the bore and locking the stem to a wall of the bore.