| 摘要 |
PURPOSE:To make it possible to easily and effectively manufacture the tank by forming the top plate and the bottom plate into an inverted bowl shape of the substantially same contour and forming expanded tube portions in the openings of these plates. CONSTITUTION:A top plate 6 and a bottom plate 7 are formed into an inverted bowl shape of the substantially same contour. Their spherical diameters R1 and sizes of expanded tub portions r1, r2 and t1 are quite the same. Further, the superimposition allowance t2 of a drum body 3 and the expanded tube portion becomes easily located by the R parts 6c and 7c of the expanded tube portion, and is substantially the same on the circumference. The top plate 6 and the bottom plate 7c are formed into an inverted bowl shape of the same contour, and the expanded tube portions are provided in the openings thereof, whereby metal molds for manufacturing the top plate 6 and the bottom plate can be used in common for male mold as well as feamale mold, the manufacturing process can be simplified, and invertment for manufacturing metal molds can also be reduced. At the same time, locating of the drum body 3 and the top plate 6 can be facilitated and the welding thereof can be carried out easily. |
