| 摘要 |
PURPOSE:To reduce thermal stress and improve the reliability thereof by a method wherein a high-temperature part helical coil heat transfer tube and low and middle-temperature part helical coil heat transfer tube are separated by an intermediate connection tube while the former is supported and suspended by a high- temperature part support beam and the latter is suspended and supported by the low and middle-temperature part support beam. CONSTITUTION:The helical coil heat transfer tube 8 is divided into the upper helical coil heat transfer tube 8a part and the lower helical coil heat transfer tube 8b part and both of them are connected by the intermediate connection tube 10 while the upper helical heat transfer tube 8a is suspended and supported by the upper support beam 15 and the lower helical coil heat transfer tube 8b is suspended and supported by the lower support beam 18. Accordingly, the thermal expansion of the upper helical heat transfer tube 8a is absorbed by the intermediate connection tube 10 so as not to affect to the lower helical coil heat transfer tube 8b or a lower connection tube 13 while the lower connection tube 13 is enough to absorb only the thermal expansion of the lower helical coil heat transfer tube 8b, therefore, the thermal stress may be reduced remarkably. |
