摘要 |
A threaded joint interconnects male and female parts of rock-drilling equipment, the female parts including an internal trapezoidal thread in the form of a helix thread ridge, which is delimited by a top and two flanks, a groove, having a bottom, running between two tops, and which thread ridge extends a plurality of turns between a front end and a rear end, the thread top touching an imaginary cylinder or cone that is concentric with a center axis of the female part. The bottom of the thread groove has a concave and partially circular cross-section shape along at least a part of the extension of the groove, and transforms into flanks via concave radius transitions, the radii of which decrease in the direction from the front end of the thread toward the rear one, at the same time as the radius of the groove bottom increases in the same direction. |