甲醇装置用废热锅炉管板的修复

Repairing of tube-sheet of waste heat boiler in methand unit

甲醇装置用废热锅炉管板在使用过程中局部出现了裂纹,为保证设备的正常运行,需进行修复。由于换热管与管板材质均为低合金耐热钢,含有较多的Cr-Mo,空淬倾向大,焊接时易出现冷裂纹,同时为了消除焊接应力和焊缝金属组织,焊后必须进行热处理。结合Cr-Mo耐热钢的焊接特点、现场施工条件和缺陷情况,制定了管板修复方案,采用手工钨极氩弧焊对管板进行修复。实践证明,所制定的管板修复方案可靠,所选用的焊接方法、焊接材料、焊接工艺规范正确合理。

Some cracks were found on the tube sheet of waste heat boiler in methand unit when operating,to assure the equipment operated safely ,It needs to be repaired ,because of the material of tube and tube sheets are all the low alloy heat resistance steel.The alloy elements of Cr-Mo is more than the common low alloy steel,So it is easy to cause cold cracks when the repairing plan is not very reasonable.At the same time,The boiler tube sheets must be heat treated after welding to relief the stress and improve the weld metal miere structure,This can take many problems.So correctly chosen welding materials,strictly controlled welding heat input and reasonable welding procedure parameters are very important to the boiler tube sheets repairing plan.The article gains a reasonable repairing plan on the repairing of the boiler tube sheets using in methand unit.