THREADED CONNECTION WITH HIGH RADIAL LOADS AND SELECTIVELY PROCESSED SURFACES Russian patent published in 2012 - IPC F16L15/06 

FIELD: machine building.

SUBSTANCE: threaded connection has preload between nipple thread grooves and coupling thread projections; at that, preload value is 1% - 5% of average connection thickness. Thread profile radius from groove to support end is 0.20 to 0.40 mm; and surface of connection is subject to processing involving shot-blasting strengthening of the beginning and end part of threaded nipple zone. In other versions the preload can be provided between grooves of coupling thread and projections of nipple thread. Threaded connection screwing methods are described.

EFFECT: invention improves threaded connection reliability.

5 cl, 5 dwg