301L方钢管裂纹产生原因分析及控制措施

Analysis and Control Measures for Cracks in 301L Square Steel Pipe

301L-1/8材料广泛应用于滚弯焊接的方钢管中,在现场检测中发现,301L-1/8的方钢管在端部折弯处出现裂纹,通过PT检测,由金相观察确定了裂纹的存在。从硬度、金相等方面分析裂纹产生机理,最后将折弯内径由2倍的板厚改变为3倍的板厚,通过检测发现裂纹得到消除。

The 301L-1/8 material is widely used in rolled welded square steel pipes.During on-site inspection,cracks were found at the end bending of the 301L-1/8 square steel pipe.Through PT testing,the existence of cracks was determined through metallographic observation.This paper analyzes the mechanism of crack formation from aspects such as hardness and gold,and finally changes the bending inner diameter from 2 times the plate thickness to 3 times the plate thickness.Through inspection,it was found that the crack was eliminated.