Abstract: An improved plate-type heat exchanger and a method for joining the plates thereof is disclosed. The heat exchanger includes a core containing a plurality of spaced parallel plates. The core is attached to the housing of the heat exchanger by means of a spray weld process and a standard weld process. In the spray weld process a filler metal is deposited on the core and the housing frame at the joint where the end portion of the plates and the housing frame meet. The filler metal used in the spray weld process forms a spray weld fillet which increases the thickness of the plates. The standard weld process further secures the plates to the heat exchanger housing frame.

Abstract: A seal is disclosed having a member of castable material. The member has a first surface and a second surface, and at least one aperture formed in the member during the casting of the member. A seal is positioned in the aperture in the member. The seal is positioned in the aperture during the casting of the member whereby the seal is secured to the member of castable material and forms a fluid tight joint with the first surface of the member.