Abstract: Under the conditions of high temperature, high pressure and bundle vibration, crevices between tube and tube sheet are easily to appear in reaction effluent steam generator. From the view of residual contact pressure of hydraulic expansion, the pipe joint should adopt strength welding and strength expansion, the slotting position should be close to the shell side, the slotting width should be appropriately increased to about 7 mm, the expansion degree should be controlled at 4%~6%, and the NS1402 heat exchange pipe should be supplied in 960 ℃ protective atmosphere high temperature annealing state. In order to prevent alkali stress corrosion, the corrosion resistance of NS1402 in alkali stress corrosion environment is compared with that of common nickel and nickel based alloys, and their suitability to tubeside medium is discussed as well. It is concluded that NS3306, NS3105 or NS3102 can replace NS1402 as an alternative material for reaction effluent steam generator tube bundle upgrading. But the vibration of equipment, manufacturing requirements, service life and cost budget should be considered comprehensively.

Key words: reaction effluent, steam generator, leakage, slotting of pipe hole, expansion controlling, bright annealing, nickel based alloys

摘要： 反应流出物蒸汽发生器在高温、高压及管束振动的工况下,管孔贴胀处容易出现间隙而发生碱应力腐蚀破坏。从保证胀接残余接触压力的角度考虑,管接头应采用强度焊+强度胀,开槽位置应靠近壳程侧,开槽宽度应适度加大到7 mm左右,胀度控制在4%~6%,对NS1402换热管应采用960 ℃保护气氛高温退火状态供货。为防止碱应力腐蚀,比较了NS1402与常见的镍及镍基合金在碱应力腐蚀环境下的耐蚀性能,讨论了其是否适用于反应流出物蒸汽发生器管程介质的腐蚀环境,得出NS3306,NS3105或NS3102可替代NS1402作为反应流出物蒸汽发生器管束升级备选材料,但应综合考虑设备的振动、制造加工要求、使用年限及成本预算等因素。

关键词: 反应流出物, 蒸汽发生器, 泄漏, 管孔开槽, 胀度控制, 光亮退火, 镍基合金