Patent ID: 8011698

Claim:
An expandable tubular joint, comprising: a first tubular male element, comprising a first male threading and a ring shaped lip having a first axial stop surface at a free end of the first element; and a second tubular female element comprising a second female threading, matching the first threading, and a receiving element matching the male lip, having a second axial stop surface, the first threading being configured to be screwed into the second threading to bring the two stop surfaces into mutual contact, and a peripheral surface of the receiving element radially facing inwards, the female element comprising a first inclined shoulder facing towards the second axial stop surface, and a peripheral surface of the first tubular male element radially facing outwards and comprising a second inclined shoulder, a peripheral surface of the receiving element radially facing inwards comprising a ring shaped channel with a concave arc profile that presents a first flank axially facing towards said axial stop surfaces and a second flank axially facing in an opposite direction to said axial stop surfaces, the inclined shoulder fitting of the receiving element being defined by said first flank, the concave channel impressing a corresponding convex shape on the peripheral surface of the male lip during expansion, wherein, upon expansion of the joint, the inclined shoulders and said corresponding convex shape are at least locally in sealed mutual contact with radial interference.