Patent ID: 7513534
Filing Date: 2009-04-07
Classification: F16L

Abstract:
1. A threaded element of a threaded tubular connection comprising: a threading with at least one threaded portion, each threaded portion comprising, starting from an end of the at least one threaded portion located on a side of a front end of the threaded element, a first engaged thread zone with at least three threads of substantially constant width, a medial thread zone having a plurality of threads with said substantially constant width, and a last engaged thread zone with at least three threads of said substantially constant width; a helical groove formed substantially radially to at least partially open at a thread crest, wherein the groove is formed in said at least three threads of one or both of the first engaged thread zone and the last engaged thread zone, and geometrical characteristics of the groove reducing a stiffness of at least the at least three threads of substantially constant width and having the groove in one or both of the first and last engaged thread zones compared with a stiffness of the threads in the medial thread zone having said substantially constant width such that the stiffness of the threads in said medial zone with said substantially constant width is greater than the stiffness of the at least three threads of substantially constant width in the one or both of the first and last engaged thread zones and having the groove.