WELLHEAD Russian patent published in 1997 - IPC

FIELD: drilling of oil and gas wells, particular, their testing in the process of drilling by tubular formation tester; applicable in equipment of drill pipe string. SUBSTANCE: installed in the body on bearings is hollow vertical bore with branch. Branch is made in form of T-piece and accommodates cylindrical shutoff and sealing device made in form of horizontal shutoff shaft with control valve. Control valve when moving may close the branch. Shutoff shaft is installed on square thread and has remote drive in form of wheel enveloped by full-line through angle of 180 deg and installed on horizontal shutoff shaft. Full-line branches form a closed ring. EFFECT: simplified process of well testing. 2 dwg