冷轧连续退火炉内带钢焊缝开裂成因与预防措施

Cause Analysis and Preventive Measures of Weldseam Breakage in Cold Rolling Continuous Annealing Furnace

山东某钢厂连续退火机组,出现多次焊缝在退火炉加热段开裂事故。经过对炉内开裂焊缝分析,发现焊缝热影响区强度低于母材强度是退火炉内焊缝断带的直接原因,下焊轮高度低、焊轮表面存在焊渣是造成焊缝质量不好的主要因素。通过焊接前检查下焊轮与夹钳台水平高度相差在±0.5 mm以内,以及对焊轮使用更换标准频次的精细化管理,降低了焊缝在连续退火炉断裂事故。

In a continuous annealing unit of a steel plant in Shandong province,weldseam cracks occurred several times in the annealing furnace heating section.Through the analysis of the cracking weld in the furnace,it is found that the direct cause of the weldseam breakage in the annealing furnace is that the strength of the heat affected zone of the weld is lower than that of the base material.By checking the horizontal height difference between the welding wheel and the clamp platform within±0.5 mm before welding,as well as the fine management of the standard frequency of replacement of the welding wheel,the accident of weldseam breakage in continuous annealing furnace can be reduced.