Abstract: Pipe coupling comprising two flanges which can be fixed to the ends of the ipes and clamping means which bear on the flanges to sealingly connect the same, wherein the clamping means comprise an extensible member located between the flanges and defining a passage providing a communication between the pipes and at least one movable member controlling the elongation of the extensible member to make it sealingly bear against the flanges, the movable member bearing on the rear face of the flanges to prevent the moving apart thereof during the elongation of the extensible member.

Abstract: Flexible joint with two sealing lines having curvilinear portions, wherein it comprises two closed elementary joints of different length, whose axes are arranged in the same plane, joined together by a shaping template which cooperates at least with the outer joint by excrescences arranged on the outer periphery of the template and defining between them recesses at least level with the curvilinear portions of the joint, each excrescence having a groove in which is received the outer joint, each of the joints having an inner spring with contiguous turns closed on itself and at least one metal casing in which is fitted the spring.The invention more particularly relates to the construction of non-circular joints.

Abstract: Pipe coupling of the type comprising two end fittings which can be fixed to two parts of the circuit to be connected and an open collar constituted by a plurality of articulated elements, with which are associated tensioning means, said elements cooperating with the end fittings to bring the latter into tightly sealed contact during the utilization of the tensioning means, wherein the collar has at least one C-shaped spring connecting each of the articulated elements and giving the collar a semi-rigid structure, there being a clearance in a direction longitudinal with respect to the spring between the latter and each of the articulated elements in order to prevent the transmission of the tightening forces to the spring.

Abstract: The present invention relates to a self-locking union or fitting adapted to be placed between two parts of a circuit to be connected, of the type comprising two end pieces adapted to be fixed to two parts of the circuit to be connected, two half-shells having internal truncated surfaces engaging complementary external truncated surfaces formed on the end pieces, to urge the latter into tight contact when the two half-shells are urged radially towards each other, wherein automatic locking means are disposed on the sides of the two half-shells, each of the half-shells being made fast with one of the end pieces by connecting means allowing a radial displacement of the half-shell with respect to the corresponding end piece, while maintaining the axis of the end piece parallel to that of the half-shell. The invention also relates to a tool particularly adapted to tighten a union or fitting of this type.

Abstract: Metalloplastic flexible annular joint, wherein it comprises a first metal ring constituted by an inner metal spring with contiguous turns closed on itself and surrounding said spring, at least one metal envelope in which is embedded the spring, said envelope being extended by two parallel planar faces which extend in a transverse equatorial plane of symmetry of the joint, said faces having flared extensions moving away from said plane at a predetermined distance from the spring to partly surround a second solid elastomer plastic ring which is coaxial to the spring in such a way as to create between the two rings a sealed enclosure of limited volume which can be used for controlling the sealing of the joint.

Abstract: Flexible annular joint having on the one hand a central core constituted by a helical spring made from metal wire with contiguous coils, which is closed on itself and in the inoperative state has the shape of a continuous ring, and on the other hand at least one envelope surrounding the central core and having in the inoperative state a cross-section formed by a curve which is not closed on itself. The internal helical spring comprises at least one continuous wire whose cross-section is a circular segment whose angle at the center is between 180.degree. and 360.degree., the chord of said segment producing the outer surface of said spring.