METHOD FOR CONSTRUCTION OF WELLS Russian patent published in 1999 - IPC

FIELD: mining industry. SUBSTANCE: method relates to construction of prospecting and operating wells, including vertical and inclined wells, and wells with horizontal end portion. According to method, bore-hole is drilled in compliance with preset profile, casing strings of different types are lowered including hidden perforated string beyond bore-hole. Casing strings are fastened by removable anchors. They are isolated in bore-hole by preliminary injection of heat-resistant, sedimentation-stable, high-structural, anticorrosive, viscous-plastic liquid acting as hydraulic seal in combination with hermetic separator of medium. Operating string is not perforated, it is fastened at well head to preceding pipe string with additional force against pushing out from bore-hole by weight of column of hydraulic seal liquid which brings its action on hermetic separator of medium from well head. Hermetic separator of medium is located in hidden perforated string above roof of productive bed. Located in its end is centralizer on rollers with hydraulic giant nozzle for washing out sediments and compensation of hydraulic-gas impacts from side of productive bed. Checking and control over annual spaces, casing clearances, and bore-hole spaces are effected by circulation of hydraulic seal liquid through hydraulic valves, medium control sensors which are installed above hermetic medium separators of all pipe strings. Removable anchors with hermetic separators are brought to transportation position. After preliminary separation of hydraulic seal liquid, tubular structures of strings together with their equipment are successively fully extracted and replaced. Application of aforesaid method ensures creation of structure which is not subjected to deformation, temperature effect, impact forces and other occurrences with possible control over annular spaces with extraction of tubular structures from bore-hole. EFFECT: higher efficiency. 4 cl, 1 dwg