Gängförband för borrsträng för slående bergborrning

摘要

In percussion rock drilling a screw joint for a drill run or drill string including male and female screw threads (5, 9) on the elements (1, 2) are joined together to form a drill string. Within the screw joint the male thread (5) and the female thread (9) have a trapezoidal shape and a slight conical inclination.