Abstract: Most of the drill pipes used by coal mine drilling rigs are connected by conical thread joints, which have good alignment and meet the working condition of one-way rotation and torsion, but can not rotate in reverse. A new type of self -locking forward and reverse drill pipe structure in the rod was studied to realize the mechanical self-locking of thread pair connection and the automatic release of drill pipe machinery. From the back to the previous releases, the drill pipe connection has good rigidity, large bearing torque and good stability, which can meet the requirements of automatic addition of drill pipe.