To provide a catalyst apparatus easy to manufacture where a stopper 4 can be attached to a casing 2 with a catalyst mat 3 in between without applying excessively high surface pressure between a catalyst carrier 1 and the catalyst mat 3.
The catalyst mat 3 is mounted between the cylindrical catalyst carrier 1 and the casing 2. The stopper 4 having a shape of a ring is attached adjacently to the catalyst carrier 1 in the direction A of gas flow. A section 2B of the casing 2 facing an outer periphery of the stopper 4 is shrunk in diameter when forming the casing 2 by a process of diameter shrinking. An extension 3B of the catalyst mat 3 projecting from the end of the catalyst carrier 1 is pressed by the above section 2B of shrunk diameter and the stopper 4 and thus the stopper 4 is attached to the casing 2 with the pressed extension 3B of the catalyst mat 3 in between.
Hiromichi Kobayashi
Tomioka Kiyoshi