Drilling string, threaded coupling, and rod adaptor for rotary drilling

A drill string for rotary drilling with underground mining machines, the drill string comprising:

• a first elongate drill string member having a main section and a male end;
• and
• a second elongate drill string member having a main section and a female end, the male end and the female end each having respective threads arranged to provide a thread coupling between the male end and the female end, the thread coupling enabling the male end to be secured inside the female end such that the male end and the female end overlap axially, wherein a thread lead of the respective threads of the male end and the female end is greater than a diameter of the male end and a diameter of the female end, wherein the thread lead is a distance along an axis of the respective thread that is covered by one complete rotation of the thread, and wherein the respective threads of the male end and the female end are right-handed threads.