CAP1400核电站设备闸门焊后热处理工艺

Post-welding heat treatment process of equipment hatch for CAP1400 nuclear power plant

CAP1400设备闸门因结构尺寸较大(插入板外径8.5 m),焊后热处理(简称PWHT)保温区间较窄(595～620℃),以及较大的板厚差(封头板厚36 mm,插入板、套筒及法兰板厚130 mm),其整体PWHT工艺难度较大。通过测定热处理炉温度的均匀性,建立有效加热区域,在该区域内进行封头法兰组件及插入板套筒组件的炉内焊后整体热处理试验,分析试验过程控制方法及热处理曲线,为大型贯穿组件的PWHT提供理论和数据支持。

With its large structure size (the outer diameter of inserted plate is 8.5 m),narrow interval (595~620 ℃) of the post-welding heat treatment(PWHT),and major difference of plate thickness (the thickness of dome head is 36 mm,the thickness of insert plate,penetration sleeve as well as flange are all 130 mm),the PWHT process for equipment hatch is a big challenge. In this paper,the temperature uniformity of heat treatment furnace is measured to establish an effective heating area,which guarantees the precision range of heat treatment temperature. In this area,PWHT tests for module of dome head and flange and module of insert plate and penetration sleeves are carried out in furnace. The analysis results of tests procedure and heat treatment curves provide theoretical and data support for CAP1400 large penetration assembly PWHT.