Patent ID: 7118139
Filing Date: 2006-10-10
Classification: F16L,Y10S,Y10T

Abstract:
1. A flanged coupling device having a static ball-and-socket joint, the device comprising: a first coupling member having a cylindrical-surface seat and a sealing surface; a second coupling member having a concave sealing surface that is substantially spherical in shape between a minimum diameter and a maximum diameter; a two-barrier metal gasket placed between the sealing surfaces of the first and second coupling members, said gasket comprising: leak monitoring means; assembly means for assembling together the first and second coupling members so as to hold the gasket between their respective sealing surfaces; and means allowing a certain amount of angular deflection between the axes of the coupling members; wherein the radius of curvature R the means allowing a certain amount of angular deflection between the axes of the coupling members are provided first by a gap A between facing front faces of the two coupling members and by radial clearance δ due to the difference between the diameters of each of the holes in the flange of the first coupling member and each of the assembly means, the angle α between the axes of the coupling members is given by the following relationship: where: A in mm is the axial gap between the face of the first coupling member and the facing face of the second coupling member when the assembled coupling members are in alignment; R β is the tilt angle relative to the axis of the first coupling member of the tangent T to the spherical surface common to the gasket and to the second coupling member at the point where its outside diameter is at a maximum, where β lies in the range 27° to 33°; and the length of the radial clearance δ due to the difference in diameter between each hole in the first coupling member and each assembling means satisfies the relationship: where H in mm is the thickness of the flange of the first coupling member, the two-barrier metal gasket placed between the sealing surfaces of the first and second coupling members is held by a retaining ring and the metal gasket is made of a refractory nickel alloy made by powder metallurgy, suitable for withstanding hydrogen, and having a uniform fine-grain structure with isotropic properties and coated in sealing layers.