Automotive exhaust component and method of manufacture

An internal combustion engine system having an exhaust system comprising a catalytic converter, having interior and exterior surfaces said catalytic converter 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.

A multi-stage 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 connecting said gas inlet port and said gas outlet port, 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 and comprising a plurality of cascaded subsections;
• 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;
• said catalytic converter having been produced by a process comprising:
• i. providing a seamless metallic tube having a first end and a second end, said preform being adapted to be formed into said housing;
• ii. swaging said first end to form said gas inlet port and said inlet transition section;
• iii. swaging said second end to form said gas outlet port and said outlet transition section;
• iv. swaging said intermediate section to form said subsections;
• and
• v. inserting said catalytic elements in said subsections.