THREADED CONNECTION FOR STEEL PIPES Russian patent published in 2021 - IPC F16L15/04 

FIELD: pipelines.

SUBSTANCE: invention relates to a threaded connection for steel pipes, containing a nipple (10) and a coupling (20). The nipple (10), in the order from the front end of the nipple (10) to the body (11) of the nipple pipe (10), comprises an annular thrust surface (12), an annular sealing surface (13) adjacent to the thrust surface (12), and a section (14) with an external thread. The coupling (20), in the order from the body (21) of the coupling pipe (20) to the front end of the coupling (20), comprises an annular thrust surface (22), an annular sealing surface (23) adjacent to the thrust surface (22), and a section (24) with an internal thread. The thrust surface (12) of the nipple and the thrust surface (22) of the coupling are declined relative to the plane perpendicular to the axis (CL) of the pipe in the nipple (10) screwing direction. The diameter (Dpi) of the inner circumferential edge (12a) of the thrust surface (12) of the nipple is smaller than the diameter (Dbi) of the inner circumferential edge (22a) of the thrust surface (22) of the coupling.

EFFECT: invention ensures sufficient sealing capacity relative to the external pressure even when using a thick-walled steel connection pipe.

5 cl, 2 tbl, 4 dwg