Patent ID: 7290623

Claim:
A drill string for a rotary-vibratory drill comprising a plurality of drill pipes, each of the drill pipes having a longitudinal axis and at least one end; a female connector member and a male connector member being between the ends of adjacent said drill pipes, the female connector member having a first portion which mates with a first of the adjacent drill pipes and a second portion extending away from the first of the drill pipes, the male connector member having a first portion which mates with a second of the adjacent drill pipes and a second portion extending away from the second of the drill pipes, the second portion of the female connector threadedly engaging the second portion of the male connector, one of said each drill pipe and the connectors having a plurality of spaced-apart slots adjacent to the end of the drill pipe and communicating outwardly at the end, the slots being parallel to the longitudinal axis, each of the connectors being connected to one of the adjacent drill pipes by welding extending about an adjacent said end of the one drill pipe and along the slots.