Abstract: A compound tapered flange assembly for sealing axially aligned flanged tubular members. Opposed annular recesses are formed in each flange. Each recess has a radial shoulder tapered with respect to a transverse plane disposed between the flanges such that the axial distance between the radial plane and the shoulder at a maximum diameter is greater than the axial distance from the plane to the shoulder at a minimum diameter. Each recess also has an inside frustoconical surface tapered with respect to the longitudinal axis with a minimum inside diameter adjacent the shoulder, and a maximum inside diameter adjacent a face of the flange. A bifrustoconical annular seal ring has outside and end surfaces complementarily tapered to engage the shoulder and the inside surface of the recesses.

Abstract: A heat exchanger closure connection including a shell closure flange extending outwardly from the shell and including a shell closure flange sealing surface. A tube closure flange extends outwardly from an inner tube, which is positioned within the shell, and includes axially spaced apart first and second sealing surfaces. A first seal ring is positioned between the first seal surface of the tube closure flange and the shell closure flange sealing surface. A split ring assembly is fitted within a groove in the tube closure flange and in abutting engagement with the shell closure flange. A locking flange is positioned about the tube closure flange engaging the first seal ring.

Abstract: Disclosed is a high pressure flow line connection. The connection includes a tubular male member, a tubular female member and a seal ring positioned between the male and female members. The male and female members have mating frusto-conical tapered surfaces, with the angle of taper of the female member being less than that of the male member. The seal ring has inner and outer tapered surfaces having angles of taper equal to those of the male and female members, respectively. The seal ring includes a radially outwardly extending lip adjacent the maximum outside diameter thereof. The male member, female member, and seal ring are cooperatively figured such that the seal ring lip remains spaced apart from the female member but optimum sealing engagement is achieved.