Abstract: A manufacturing method of a catalyst container includes forming a plate member that is partially different in plate thickness or material by joining material plates that are different in plate thickness or material by welding; bending the plate member that is partially different in plate thickness or material to form a hollow material, wherein the hollow material is formed by bending the plate member and joining opposing sides thereof by welding; and changing a sectional shape of the hollow material by a spinning process.

Abstract: Individual plate members (W1, W2, W3, W4, W5) that are different in plate thickness or material are joined together by mush seam welding to form hollow material (W, W′), and the rigidity is controlled in individual parts. By spinning the rigidity material (W, W′), a junction (1b) and a cone (1c) are formed in an optimum shape, and a hollow member (1) is manufactured. Thus, the hollow member (1) smooth in juntion and high in welding strength is obtained in spite of thin plate material. When this hollow member (1) is used in a catalyst container, the sealing performance is excellent without being accompanied by an increase in radiant noise or an increase in weight.