Abstract: Slurry steam generator is an important heat capture and energy saving equipment in catalytic cracking unit. Whether the equipment can run efficiently for a long period directly affects the energy consumption index level of the catalytic unit. In 2019, after a catalytic unit expansion and transformation project was completed and started in a refinery, two new slurry steam generators had leakage faults in tube bundle within one month, which had a great impact on the normal operation of the whole unit. After opening the cover and maintenance, it was found that a wide range of cracks occurred in the heat affected zone of the welding between the tubeplate and the heat exchange tube, resulting in the cracking of the evaporator tubeplate and the leakage of oil slurry. The tube bundle design, material and welding process are improved to effectively solve the tube plate cracking fault of oil slurry steam generator. The improved heat exchanger operates well and ensures the long term and stable operation of the unit.

Key words: slurry steam generator, tube sheet, cracking, temperature difference, SCC, sulphur content, welding stress

摘要： 油浆蒸汽发生器是催化裂化装置的重要取热节能设备，该设备能否长周期高效运行,直接影响到催化裂化装置运行能耗指标水平的高低。2019年,某炼油厂1号催化裂化装置扩能改造项目完成投运后，新增的两台油浆蒸汽发生器在1个月内,相继发生管束内漏故障，对整套装置的正常运行产生较大影响。开盖检修后检查发现两台管束管板与换热管焊接热影响区都发生大范围裂纹，导致蒸发器管板开裂油浆内漏。针对该故障从管束设计、材料、焊接工艺等方面进行了改进，有效地解决了油浆蒸汽发生器管板开裂故障，改进后的换热器运行状况良好，确保了装置长周期安稳运行。

关键词: 油浆蒸汽发生器, 管板, 开裂, 温差, 应力腐蚀开裂, 硫含量, 焊接应力