Abstract: Heat conductive fins (107) are welded along both sides of a belt-like member (105a) with a margin left along edges of the both sides, thereby to form a unit (105c). The unit (105c) is welded to a body (101) with the heat conductive fins (107) from the outside of each fin. Next, another belt-like member (105b) is covered over a gap between adjacent belt-like members (105a, 105a), and these members are welded from the outside. With this arrangement, there is no need to weld in a narrow and long space and the entire welding step is carried out from the outside, which makes it easier to assemble a cask.

Abstract: Heat conductive fins (107) are welded along both sides of a belt-like member (105a) with a margin left along edges of the both sides, thereby to form a unit (105c). The unit (105c) is welded to a body (101) with the heat conductive fins (107) from the outside of each fin. Next, another belt-like member (105b) is covered over a gap between adjacent belt-like members (105a, 105a), and these members are welded from the outside. With this arrangement, there is no need to weld in a narrow and long space and the entire welding step is carried out from the outside, which makes it easier to assemble a cask.

Abstract: The absorbing rods have a nearly the same shape as the shape of columnar control rods for PWR used in reactivity control of core in a reactor. The absorbing rods can shield neutrons, and are inserted in control rod guide pipes and measuring pipes in fuel assemblies.

Abstract: Heat conductive fins are welded along both sides of a belt-like member with a margin left along edges of the both sides, thereby to form a unit. The unit is welded to a body with the heat conductive fins from the outside of each fin. Next, another belt-like member is covered over a gap between adjacent belt-like members, and these members are welded from the outside. With this arrangement, there is no need to weld in a narrow and long space and the entire welding step is carried out from the outside, which makes it easier to assemble a cask.

Abstract: Heat conductive fins are welded along both sides of a belt-like member with a margin left along edges of the both sides, thereby to form a unit. The unit is welded to a body with the heat conductive fins from the outside of each fin. Next, another belt-like member is covered over a gap between adjacent belt-like members, and these members are welded from the outside. With this arrangement, there is no need to weld in a narrow and long space and the entire welding step is carried out from the outside, which makes it easier to assemble a cask.