Patent ID: 8561725

Claim:
A bottom hole assembly comprising a first drill collar in communication with a drilling string and a drill bit, wherein the first drill collar is formed substantially entirely from a metal matrix material comprising a matrix of tungsten carbide particles having at least one metal alloy disposed within spaces between said particles, wherein the first drill collar has a bore extending therethrough for permitting flow of drilling fluids, wherein the first drill collar comprises a first yield strength and the drilling string comprises a second yield strength, and wherein the metal matrix material and the at least one metal alloy minimize lateral movement or vibration of the first drill collar during drilling; and a transition drill collar disposed between the drilling string and the first drill collar, wherein the transition drill collar comprises a third yield strength greater than the first yield strength and less than the second yield strength such that lateral movement and vibration of the drilling string is transferred to the transition drill collar prior to transference of the lateral movement and vibration to the first drill collar, wherein the first drill collar comprises a first channel extending therethrough on a first side of the first drill collar and a second channel on a second side of the first drill collar opposite the first side, and wherein the second channel prevents unbalancing of the first drill collar.