Title:
TUBULAR THREADED JOINT WITH TRAPEZOID THREADS HAVING CONVEX BULGED THREAD SURFACE
Document Type and Number:
WIPO Patent Application WO2002065012
Kind Code:
A9
Abstract:
The invention concerns a tubular threaded joint comprising two male and female threaded elements one screwed into the other with a specific torque wherein at least one thread surface under contact pressure (125) has prior to being screwed a continuous convex bulged shape over its bending radius length ranging between 2 and 60 mm and is in point-to-point contact with the corresponding surface (26) of the conjugate element. Such a threaded joint exhibits enhanced screwing and unscrewing strength. In one embodiment, the convex bulged surface (125) is a male or female thread flank and one of the male or female threads comprises a groove (31) emerging at the thread crest (29) to make, as the case may be, either the convex bulged flank (125) or the corresponding flank flexible. Such a geometry enables to accommodate contact variations between the flanks.
Inventors:
NOEL THIERRY (FR)
ROUSSIE GABRIEL (FR)
VARENNE EMMANUEL (FR)
ROUSSIE GABRIEL (FR)
VARENNE EMMANUEL (FR)
Application Number:
PCT/FR2002/000420
Publication Date:
July 24, 2003
Filing Date:
February 04, 2002
Export Citation:
Assignee:
VALLOUREC MANNESMANN OIL & GAS (FR)
SUMITOMO METAL IND (JP)
NOEL THIERRY (FR)
ROUSSIE GABRIEL (FR)
VARENNE EMMANUEL (FR)
SUMITOMO METAL IND (JP)
NOEL THIERRY (FR)
ROUSSIE GABRIEL (FR)
VARENNE EMMANUEL (FR)
International Classes:
F16B7/18; F16L15/02; F16L15/00; F16L15/06; (IPC1-7): F16L15/06
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