Abstract: A plate and fin type heat exchanger in which different flowing fluids are placed in a segregated heat transfer relation and in which provision is made to deny opportunity for a leaked fluid from one flow or circuit to join or mix with fluid of another flow or circuit. A concept of vented buffer zones is used to protect against leakage through plate elements and through defined joints between plate and spacer elements. The concept allows and provides for relatively simple manifolding and for fabrication to conventional configurations using for the most part standard easily manufactured parts.

Abstract: A self-locating sealing assembly in which a compressible sealing member and an encircling retainer ring make an assembly for sealing non-grooved joints. The sealing assembly has special application to a standard type pipe flange having a relatively projected sealing surface. The sealing assembly has clip type locating means which make a peripheral engagement with the projected sealing surface concentrically to locate the sealing assembly and to hold it located while the joint is being closed.