Patent ID: 6206115
Filing Date: 2001-03-27
Classification: E21B

Abstract:
An earth-boring bit comprising:a bit body;at least one earth disintegrating cutter, the cutter being generally conically shaped and rotatably secured to the bit body;a plurality of teeth formed on the cutter, at least one tooth of the teeth comprising:a steel stub integrally formed with and protruding from the cutter, the stub having a pair of flanks which incline toward each other relative to an axis of the tooth and terminate in a top;a carburized layer formed on the flanks and the top to a selected depth, the depth of the carburized layer being substantially uniform on all surfaces of the stub;the distance between the flanks, measured perpendicular to the axis at the top, being greater than twice the depth of the carburized layer;a layer of tube hardfacing coated on the top and flanks of the stub and forming an apex for the tooth; andwherein the hardfacing has a thickness measured along the axis of the tooth from the top of the stub to the apex formed by the hardfacing which is at least 3/16 inch.