Special round thread for rotary percussive drilling work with great ease of threading which speeds up work, whilst being able to work with a male/female thread or male/male thread with external coupling with a minimum length of 50 mm and a maximum length of 150 mm. The minimum length of the external coupling is 120 mm and the maximum is 250 mm. We are able to thread pipes up to 6.5 m in length. The minimum diameter that can be threaded is 60.3 mm and the maximum is 219 mm.