| 摘要 |
PURPOSE:To keep the tightening force of a clamping bolt from decreasing when flanges are warmed up by high-temperature steam, by providing a protective layer of a substance with a low thermal conductivity around the clamping bolt for the contact portions of the flanges. CONSTITUTION:High-temperature steam S in a casing 1 flows into a bolt hole 6 through a steam hole 7 but the steam does not come into contact with a clamping bolt 3 and goes around a protective cylinder 9 of low thermal conductivity as shown by arrows. The steam S is then conducted to the next bolt hole through a communication hole 8 and finally flows into the low-temperature part of the casing 1. Thick flanges 2a, 2b are warmed up in a short time by the steam S but the bolt 3 is prevented by the protective cylinder 9 from being heated. For that reason, the tightening force of the clamping bolt 3 for the contact faces of the flanges 2a, 2b is kept high. |
