Threaded tube joint

摘要

A threaded tube joint for oil extraction industry has a trapezoidal thread and a toroidal sealing surface ( 11 ) placed at its end near the thread and engages, for sealing, a corresponding frusto-conical sealing surface ( 12 ) wherein the toroidal sealing surface ( 11 ) has a radius Rs value comprised within the range given by the formula $\frac{E}{2\mathrm{Vo}}{\left(\frac{b}{2.15}\right)}^2<=\mathrm{Rs}<={\frac{\mathrm{delta}.E^2{\mathrm{tn}}_n^3{\mathrm{OD}}^2}{240\mathrm{pi}.{\mathrm{sigma}}_{\mathrm{ad}}^2{\mathrm{wt}}^2\left(1-{\mathrm{upsilon}}^2\right)}\left[\frac{3\left(1-{\mathrm{upsilon}}^2\right)}{R_n^2{\mathrm{tn}}^2}\right]}^{3/4}.$