大规格中碳非调质圆钢超声波探伤不合格的改善研究

Study on Improvement of Ultrasonic Flaw Detection in Large Size Medium Carbon Nonquenched and Tempered Round Steel

通过对φ110大规格49MnVS3圆钢超声波探伤不合格的原因进行定位分析,认为主要为连铸坯中心疏松遗传所致。对拉速、M-EMS和F-EMS、轻压下等连铸工艺参数进行了优化研究。结果表明,当拉速为0.6 m/min、M-EMS和F-EMS的扭矩分别设定为130和420 cm·cN时可以使φ110圆钢探伤合格率提高至94%以上。

The positioning analysis of the ultrasonic flaw detection on φ110 large-size 49 MnVS3 round steel was carried out, which was considered to be mainly due to the central porosity of the continuous casting billet. The process parameters of continuous casting such as drawing speed, M-EMS and F-EMS, and light pressure were optimized. The results show that when the drawing speed is 0.6 m/min, the torque of M-EMS and F-EMS is set to 130 cm·cN and 420 cm·cN, respectively,the φ110 round steel inspection qualification rate can be increased to more than 94%.