Patent ID: 8313264

Claim:
A joint comprising a first flanged member and a second flanged member adapted for a pressure equipment device, said first and second flanged members each comprising: at least one flanged end having an end surface comprising a load transferring surface through which forces are transferred when connecting together said first and second flanged members in an assembled state, wherein, for the first flanged member, at least a portion of the load transferring surface in an unstressed condition is concave in a radial direction, such that the at least the portion of the load transferring surface is defined by a concave curve function, said load transferring surface is concave in the radial direction over at least an area that is subjected to deformation when the first flanged member is assembled together with said second flanged member, and any first point on the at least the portion of said load transferring surface and any second point of the at least the portion of said load transferring surface distal to the first point meeting a plane inclined in the radial direction of said first flanged member, wherein said load transferring surface has an outermost abutment point in a cross section of the first flanged member, the outermost abutment point configured to abut against the end surface of the second flanged member when assembled together with said corresponding second flange member, the outermost abutment point being the abutment point situated farthest in the radial direction from the central axis of the first flanged member, said load transferring surface has an innermost abutment point in a cross section of the first flanged member, the innermost abutment point configured to abut against the end surface of the second flanged member when assembled together with said corresponding second flange member, the innermost abutment point being the abutment point situated nearest in the radial direction from the central axis of the first flanged member; and a boring passing through the end surface of the first flanged member at a radial distance from a central axis of the first flanged member greater than the radial distance from the central axis of the first flanged member to the innermost abutment point, and less than the radial distance from the central axis of the first flanged member to the outermost abutment point, wherein the load transferring surface of the first flanged member faces the load transferring surface of the second flanged member before assembly and is inclined in the radial direction outwards to form an angle in radial cross-section, the angle being such that a distance between the two load transferring surfaces increases in the radial direction outwards, said inclined load transferring surfaces being concave.