ANTI-FLIGHT DEVICE Russian patent published in 2001 - IPC

FIELD: oil and gas industry, prevention of fall of drilling equipment on face of well. SUBSTANCE: anti-flight device includes upper and lower adapters, shaft. Bearing ring is installed in upper part of shaft and shock-absorbing unit with cone and anchoring mechanism are mounted for interaction beneath. Symmetric shaped grooves are made in shaft beneath cone. Shaped grooves include short and long sections. These sections are interconnected by leveling section with inclination angle of 45 degrees. Long section extends from lower part of cone to lower adapter. Length of short section is equal to doubled length of minimal injury of tool during lowering- lifting operations. Distance from lower part of cone to upper part of short section of shaped groove is equal to height of anchoring mechanism. One-way locking device is installed in shaped groove, at entrance of leveling section into long one. Through hole in which sheared lockpin fixing cone is placed is drilled in cone and shaft. Anchoring mechanism is made of body mounted on shaft for axial movement and double action grippers installed uniformly over circumference of body and spring-loaded against it. Lower parts of grippers has form of chuck jaws and their upper parts carry teeth. Anchoring mechanism includes ring put on body, girdling grippers and presenting axis with reference to which grippers swing. Casing is mounted in lower part of body for radial rotation relative to it and is made fast to it in axial direction. Diametrically opposite guiding pins are interference fitted perpendicular to axis of mechanism. EFFECT: increased functional reliability of device. 5 dwg