LOCK CONNECTION OF HOLLOW BORING FLIGHTS Russian patent published in 2004 - IPC

FIELD: well-boring equipment. SUBSTANCE: device has interconnected engagement parts in form of projections and grooves of coupling and nipple of pipe ends being connected, at least one insert in form of a plate, placed in bed hollow, which is formed by connection of coupling and nipple, and insert clamp, which is placed in insert groove. Plate is figurate with thinned central portion and widened end portions with side cylindrical surfaces. Outer surfaces of nipple and coupling have pairs of stops with hollows, forming said bed hollow in a form, congruent to the form of said plate end parts. EFFECT: increased reliability of lock connection. 4 dwg