To prevent the generation of a crack and defective appearance in a weld section of an end part owing to drawing by preliminarily making a cylindrical body having notches of the size suitable to drawing quantity in the end part and applying drawing to the end part thereof.

A flat plate 2 is formed into a cylindrical shape by bending, and the abutting end edges 2a are welded. In such a way, a cylindrical body 1 respectively having two notches 3 in both end parts 1a is made. Two notches 3 which are formed in each end part 1a are arranged in symmetrical positions. Drawing is applied to each end part 1a of the cylindrical body 1 with a press. For this purpose, the end parts 1a of the cylindrical body 1 are arranged vertically, the end parts 1a are pressed from the upside and downside with the press, and whereby drawing is executed so that first side edges forming each notch 3 abut on each other. Thus, the end part 1a of the cylindrical body 1 equivalent to the length corresponding to the depth of the notch 3 is gradually reduced in diameter at a ratio corresponding to the size of the notch 3. The abutting part of the notch is joined by welding.