Sealing element for composite pipes and pipe joint including said element

Claim 1

AUTOMATICALLY SEALED JOINED BETWEEN TWO COMPISITE TUBULAR ELEMENTS EACH OF WHICH IS PROVIDED WITH A BELL END AND A SPIGOT END AND EXTERNALLY ON THE CYLINDRICAL PART THEREOF WITH A THIN RIGID SHEATH WHICH TERMINATES AT A DISTANCE FROM THE ENDS OF THE CORRESPONDING TUBULAR ELEMENT, SAID JOINT COMPRISING A SEALING RING HAVING AN ANNULAR POLYGONAL-SECTIONED MASSIVE BODY PORTION EXTENDED BY AN ANNULAR LIP PORTION WHICH TERMINATES IN AN ANNULAR BULGE PORTION HAVING A RADIAL EXTENT LESS THEN THAT OF THE MASSIVE BODY PORTION AND HAS A CONSTRICTION ADJACENT THE MASSIVE BODY PORTION TO WHICH IT IS CONNECTED INTERNALLY BY A FIRST ANNULAR SHOULDER AND EXTERNALLY BY A SECOND ANNULAR SHOULDER WHICH HAS A RADIAL EXTENT SUBSTANTIALLY HALF THE RADIAL EXTENT OF SAID MASSIVE BODY PORTION, SAID SEALING RING BEING DEFORMED RADIALLY IN THE PART THEREOF CORRESPONDING TO SAID MASSIVE BODY PORTION BETWEEN THE INNER FACE OF THE BELL END OF ONE OF THE TUBULAR ELEMENTS AND THE PART OF THE SPIGOT END OF THE OTHER TUBULAR ELEMENT WHICH IS DEVOID OF SAID SHEATH, WHEREAS THE LIP PORTION OF THE SEALING RING DIRECTED TOWARD THE ENTRANCE OF THE BELL END IS ELASTICALLY CLAMPED ON THE THIN SHEATH OF SAID OTHER TUBULAR ELEMENT AND THE END FACE OF SAID THIN SHEATH ABUTS AGAINST THE FIRST SHOULDER OF SAID SEALING ELEMENT.