制氢转化炉下猪尾管系的改造

Revamping of outlet pigtail systems of hydrogen reformer furnace

某制氢转化炉下猪尾管采用"弯管式下猪尾管+冷壁集气管"形式,投产十多年来,下猪尾管与炉管焊缝连接处多次出现泄漏,下猪尾管与冷壁集气管的连接部位也多次发现裂纹,下猪尾管系存在安全隐患。通过多次技术论证,2017年底对制氢转化炉进行了隐患治理改造,采用ASME B31. 3—2016最新的许用应力值,重新核算了下猪尾管,将下猪尾管规格由35 mm×5. 0 mm升级为35 mm×5. 5 mm,更换了全部下猪尾管。此次隐患治理,采用了多项新技术,如:重锤滑轮组悬吊下猪尾管、下猪尾管采用柔性伸缩保温套保温等,为弯管式下猪尾管系的改造积累了经验。

The outlet pigtails systems of a hydrogen reformer furnace is ＂bending pigtail pipe ＋ cold collector＂. In the past 10 years＇ operation, the leaking occurred many times at the weld connections between outlet pigtail and reformer tube. In addition, the connection between the outlet pigtail and cold collector also cracked many times. Therefore, the safety hazards existed in the outlet pigtail systems. At the end of 2017, the hydrogen reformer furnace was revamped to remove the safety hazards. In the revamp, the latest allowable stress in ASME B31. 3--2016 was applied to recalculate the pigtail pipe, and the specification of φ35mm×5.0mm mm was upgraded to φ35mm×5.5 mm. All the outlet pigtails were replaced. A number of state-of-the-art technologies have been applied in the trouble shooting, such as： the outlet pigtail is suspended by heavy hammer pulley block, and the outlet pigtail is heat insulated by flexible insulation jackect. Extensive experience has been accumulated for the revamping of outlet pigtail systems.