| 摘要 |
PROBLEM TO BE SOLVED: To obtain a container suitable for filling the high pressure substance, to which a thick necked part is formed without using a dedicated heating device by performing press forming thickly to an only opening part in a prescribed range at the room temperature to a blind cylindrical stock, and performing necking press working at the room temperature to the thick opening part. SOLUTION: By performing the compression working of a tip part at the room temperature to the opening part of the blind long cylindrical stock, an only part in the prescribed range of the opening part is thickened and formed. By inserting a mandrel 30 into the cylindrical hole 28 of this stock, by pushing the mandrel 30 into a hole with a prescribed shape of a drawing die 32 while driving the mandrel 30 downward, and by making a thickened part project inside, the stock 34 is formed. The thickened part of the stock 34, which has been extended outside from a cylindrical outer peripheral surface, is extended in the inside of the cylindrical hole 28. By inserting the mandrel into the hole of this inside thickened part 36, and by performing press necking working so that an aperture is contracted by using a die from the surroundings of the outside of the inside thickened part 36, the necked part is formed. |
