FIELD: combination working of metals, restoration and strengthening of cone threaded surfaces.
SUBSTANCE: tool used, mainly for working oil production pipes includes body having in outlet end working zone with threaded surface reciprocal to worked thread. In order to increase useful life period and to provide fault-free operation, threaded surface of tool has normal values of conicity, mean diameter in main plane, profile angle and pitch for worked thread. Threaded surface has height of thread profile more than normal profile height of worked thread but less than normal value of height of initial acute-angle profile from which standard rounding radius of profile indentation of worked thread is extracted. Rounding radius of apex of threaded surface profile may be less than standard rounding radius of indentation of worked thread but it is more than half of said value.
EFFECT: increased useful life period of worked parts.
2 cl, 3 dwg
