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

FIELD: engineering elements.

SUBSTANCE: invention relates to a threaded connection for steel pipes, containing a nipple (10) containing a section (11) with a conical external thread and a thrust part, and a coupling containing a section with a conical internal thread and a thrust part. In the screwed position wherein the thrust parts are adjoining, the depressions (13) on the section (11) with an external thread are adjoining the vertices on the section with an internal thread, interacting with the vertices, and gaps are provided between the vertices (12) on the section (11) with an external thread and the depressions on the section with an internal thread. In the longitudinal section containing the axis (CL) of the threaded connection pipe, the vertices (12) on the section (11) with an external thread are formed by a convex curve passing tangentially to first angular sections (12a) in the shape of an arc connecting the vertices (12) with the support sides (15) and to second angular sections (12b) in the shape of an arc connecting the vertices (12) with the embedded sides (14). A solid lubricating coating (30) is formed on the surface of the section (11) with an external thread.

EFFECT: invention is capable of preventing problems with screwing without loss in the productivity in relation to the threaded connection.

6 cl, 7 dwg, 1 tbl