PURPOSE: To provide the screwed joint of high durability by comprising a socket and the pipes, mounting a seal bushing in an annular space of the socket, forming the engagement parts on the pipe ends, and projecting the pipe over the unthreaded section.
CONSTITUTION: In a screwed joint structure of a socket 6 and the pipes 2, 3 having the threaded parts 7, 8, 10, 11, an annular space is defined on an unthreaded part 9 of the socket 6, and a seal bushing 16 is mounted in this annular space and fixed by the recesses 14 of the pipe ends. The form-locked engagement parts 21, 22 are formed on the pipe ends with the axial clearance 23, 23'. The pipe 2 is projected over an end of the unthreaded part 9 of the socket 6, and its outside diameter is slightly smaller than the radial elongation of a shoulder part 24 of the socket. As a result, the screwed pipe joint structure having the durability to a medium including hydrogen sulfide can be provided.
EERIHI KUATOFURIIKU
FURIIDORIHI RENTSUE
GERUHARUTO KURUUKU
YOOZEFU JIIKUMAIYAA
