二急冷换热器是大庆乙烯九号裂解装置中,将经过了一急冷锅炉冷却的裂解气进一步进行冷却的设备,属于第三类压力容器。其壳程介质为饱合水蒸气,设计压力11.8MPa,设计温度343.3℃。由于工况条件恶劣,经过几年运行,该设备发生损坏,需要修复。 为节省工期,尽快恢复生产,决定只更换损坏的换热器芯子。为了能将芯子顺利抽出,需将壳体割开,待新芯子就位后,再对壳体进行焊接。壳体材料 Second quench heat exchanger is Daqing ethylene cracker on the 9th, will be after a cooling boiler cooling cracked gas for further cooling equipment, belonging to the third type of pressure vessel. The shell-side medium is saturated steam, design pressure 11.8MPa, design temperature 343.3 ℃. Due to poor working conditions, after several years of operation, the equipment is damaged and needs to be repaired. To save time, restore production as soon as possible and decide to replace only the damaged heat exchanger core. In order to be able to successfully extract the core, the need to open the shell until the new core in place, and then shell welding. Shell material