THREADED CONNECTION OF DRILL STRING SECTIONS Russian patent published in 2021 - IPC E21B17/42 

FIELD: mining industry.

SUBSTANCE: invention relates to drilling equipment and concerns the connection of sections of drilling screws or pipes in drill strings. The threaded connection of the drill string sections contains a coupling and a nipple mated to each other by a cylindrical non-self-braking, predominantly rectangular, thread. The initial part of the body of the inlet turn of the nipple thread is provided with a hook protruding above its working surface. The width of the screw groove of the thread exceeds the width of the screw protrusion associated with it by at least the height of the mentioned hook. The last turn of the coupling thread is limited by a cylindrical recess. The body of at least this turn of the coupling thread at the outlet to the recess is crossed by a groove, which, in the semi-unscrewed position of the threaded connection, has the possibility of coupling with the hook of the inlet turn of the nipple.

EFFECT: elimination of spontaneous, unauthorized unscrewing of the threaded connections of the drilling string, leading to its loss.

3 cl, 5 dwg