WELDED HEAT EXCHANGER AND METHOD OF MAKING

摘要

A corrosion resistant weldment heat exchanger for exchanging heat between fluids including a tube bundle having spaced tubes of flattened cross section between generally elliptical ends of corrosion resistant metal that is either copper, aluminum, brass or stainless steel and through which tubes one of the fluids flows and over the outer surface of which tubes a second fluid flows for exchange of heat between the fluids through the walls of the tubes. Headers are provided at opposite ends of the tube bundle also of the corrosion resistant metal and into which headers the ends of the tubes extend in close fitting fluid flow relationship and the tube ends and the portions of the headers receiving the tube ends being of elliptical configuration to provide an elliptically shaped joint. The tube ends and the headers are joined at the elliptical joint configurations by welds consisting substantially only of the metal of the tube ends and headers previously heated without the use of an added welding metal to a molten state by an inert gas-shielded electric arc in order to protect the welds from contamination during their formation.