The main objective of a heat exchanger or heat recovery system is the recovery of the energy by transferring the heat of the air that is extracted from the inside of a premise to the air that is driven outside. While An exhaust heat recovery system turns waste heat energy in exhaust gases into electric energy for batteries or mechanical energy reintroduced on the crankshaft. The technology is of increasing interest as car and heavy-duty vehicle manufacturers continue to increase efficiency, saving fuel and reducing emissions. A typical example, Metalli developed a series of exhaust gas recovery heat exchangers for auto cars which help save fuel consumption efficiency and reduce environment pollution.