DEVICE FOR CONNECTION OF DRILL PIPES Russian patent published in 2009 - IPC E21B17/02 

FIELD: oil and gas industry.

SUBSTANCE: invention is related to drill tool, namely, to devices for connection of drill pipes during rotary drilling of wells of different purpose. Mentioned result is achieved by the fact that device includes accessory in the form of lock nipple and coupling with thread, at the ends of which two ratchet semi-clutches are installed being rigidly connected to them, and their contact surfaces are arranged in the form of protrusions and their congruent cavities, for perception and transfer of torque moment simultaneously with threaded joint. Height of protrusions and cavities at every ratchet semi-clutch is defined from analytical expression: H=0.8 S / Z, where H is height of protrusion or cavity depth, S is thread pitch, Z is number of protrusions or cavities in every ratchet semi-clutch. Pitch of thread that joins lock nipples and coupling makes value that is equal to not more than j of its working part length. On internal surface of every ratchet semi-clutch there are through longitudinal grooves for installation of fixators in them, which are arranged in the form of L-shaped planks with springs, and width of planks is slightly less than width of through longitudinal grooves.

EFFECT: increased reliability with tight connection of drill pipes, and also prevention of their tightening against effect of considerable torsional forces that occur in process of well drilling.

4 cl, 5 dwg