Patent ID: 7252808

Claim:
A catalytic converter for an internal combustion engine exhaust system, and the converter having interior and exterior surfaces comprising: a. a single-piece, seamless metallic housing; b. a tubulated gas inlet port in said housing through which exhaust gas is introduced; c. a tubulated gas outlet port in said housing through which the exhaust gas is discharged; d. a tubulated intermediate section of said housing having an inlet end and an outlet end, said intermediate section having a plurality of rib; e. an inlet transition section connecting said inlet port and said inlet end of said intermediate section; f. an outlet transition section connecting said outlet end of said intermediate section and said outlet port; and g. a plurality of cascaded catalytic elements contained within said intermediate section and through which said exhaust gas passes sequentially when flowing between said gas inlet port and said gas outlet port; the interior surfaces of said intermediate section said inlet and outlet transition sections and said gas inlet and outlet ports having been swaged and being smooth and substantially ridge-free.