Threaded tube joint having a metal-to-metal seal

Claim 1

A JOINT FOR METALLIC TUBULAR ELEMENTS EMBODYING MALE AND FEMALE MEMBERS HAVING ENGAGEABLE THREADS OF RELATIVELY LONG PITCH DISPOSED ON A RELATIVELY STEEP TAPER, WITH THE THREADS HAVING LOAD BEARING AND NON-LOAD BEARING FLANKS, THE LOAD BEARING FLANKS HAIVNG A NEGATIVE FLANK ANGLE, AND NON-LOAD BEARING FLANKS HAVING A POSITIVE FLANK ANGLE FORM ABOUT 30* TO ABOUT 60*, THE SAID FEMALE MEMBER HAVING FULL THREADS, AND SAID MALE MEMBER HAVING VANISHING THREADS, SAID THREADS ON SAID MALE MEMBER, WHEN SAID JOINT IS MADE UP, BEING ENGAGED THROUGHOUT THEIR LENGTH, AND SAID MALE AND FEMALE MEMBERS HAVING COMPLEMENTARY TAPERED SEALING SURFACES AXIALLY DISPLACED AND RADIALLY OFFSET FROM SAID THREADS SO AS TO MAKE FULL CONICAL SURFACE CONTACT THROUGHOUT SUBSTANTIALLY THEIR OVER-LAPPED LENGHT, WITH ONLY SURFACE DEFORMATION OF THE COMPLEMENTARY SEALING SURFACE; ONES, AT LEAST, OF SAID COMPLEMENTARY SEALING SURFACES BEING CONTOURED TO PRESENT A SCALLOPED PROFILE, SAID SCALLOPOED PROFILE BEING CONSTITUTED BY CIRCUMFERNTIALLY EXTENDING POCKETS, AND THE TAPERED SEALING SURFACE ON SAID FEMALE MEMBER TERMINATING IN AN INTERNAL SHOULDER SPACED FROM THE END OF THE TAPERED SEALING SURFACE OF THE MALE MEMBER WHEN SAID JOINT IS FULLY MADE UP AND TONGED, WHEREBY UPON EACH NEW MAKE UP AND DISASSEMBLY OF SAID JOINT, FRESH INCREMENTS OF COMPLEMENTARY SEALING SURFACES COME INTO ENGAGEMENT.