| 摘要 |
PURPOSE:To prevent the deformation due to rotation stopping welding and absorb the thermal expansion of a heat shielding plate due to a temperature difference by providing a flat plate with a pin between the heat shielding plate and a nut at the stopping end of a tie rod for fixing the heat shielding plate. CONSTITUTION:In order to fix a heat shielding plate 11, screw threads are tapped at several places in the radial and circumferential directions of a thick lower tube plate 8 to attach tie rods 17, corresponding to the diameter of a heat transfer tube 9, vertically. One small hole is provided on the upper surface of the heat shielding plate 11 in order to fit a flat plate 19 with a pin. The flat plate 19 with pin is incorporated between the heat shielding plate 11 and a nut 18 in the condition of metal touch and is clamped by the nut 18. In order to prevent looseness between the nut 18 and the tie rod 17, rotation preventing welding is applied on the whole periphery of the flat plate 19 with pin, the nut 18 and the tie rod 17 respectively. The flat plate 19 with pin is provided to prevent the looseness by welding indirectly without applying the rotation preventing welding directly on the nut 18 and the heat shielding plate 11. |
