METHOD OF MANUFACTURE OF CASING CENTRALIZER Russian patent published in 2003 - IPC

FIELD: drilling of oil and gas wells; applicable in manufacture of centralizers designed for fastening of casing strings in wells of any type. SUBSTANCE: method includes making rings integral with centering ribs. Centralizer rough workpiece is stamped from sheet springy steel. Performed for one operation are cutting out from rectangular sheet of, at least, a row of windows with formation of connectors and bands, bending of workpiece into cylinder, connecting of cylinder ends to form rings from bands, upsetting of cylindrical workpiece in axial direction with profiling of connectors into curves of centering ribs, and finished product is subjected to heat treatment. After cutting-out of windows in sheet, rectangular sections for formation of hinged lock members are cut-out on band ends, hinged lock members are bent, and lock members, after imparting cylindrical shape to workpiece, are interconnected by installing steel rods into their holes. Band ends are connected by welding. EFFECT: reduced labor input in manufacture of centralizers and their costs, simplified production process, increased productivity of labor, simplified designs of machining attachments and extended field of centralizer application. 3 cl, 8 dwg