Provided is a compact threaded joint which has excellent sealing performance against
internal pressure and sealing performance against
external pressure, has excellent strength against compressive loads, and can maintain sealing performance against
external pressure even when repeated loads are applied. Provided is a compact threaded joint in which
external pressure seal sections (21, 31) and
internal pressure seal sections (23, 33) are provided in front of and behind threaded sections (22, 32), a
nose section (24) for maintaining
internal pressure sealing performance is provided at the tip of a pin (2), and torque shoulder surfaces (25, 35) are provided at the tip of the
nose section (24). When a
compressive load is applied, a portion of the
compressive load is applied by contact between the
insertion surfaces of the threaded portions (22, 32). Furthermore, by reducing the shoulder angle (theta) of the torque shoulder surfaces (25, 35), the amount of press-fit of the male buckle (2) with respect to the female buckle (3) and the amount of radially inward shrinkage deformation of the opening end of the female buckle (2) when a
compressive load is applied are reduced, and accumulation of damage in the vicinity of the outer sealing surface is suppressed.