METHOD OF EXTRACTION OF BROKEN THREADED MEMBERS FROM HOLE WITH INNER THREAD Russian patent published in 1997 - IPC

FIELD: mechanical engineering; repair of threaded joints with broken male member. SUBSTANCE: according to proposed method conical axial hole is made in broken threaded member and thread is cut in hole by taper tap. Direction of thread cut in hole should be opposite to direction of thread in female part. Then bolt with taper thread is turned into conical hole, torque is applied to bolt and broken threaded member is taken out. Description of invention provides mathematical ratio for choosing maximum diameter of conical hole. EFFECT: facilitated extraction of broken member. 2 cl, 1 dwg