钢管2026，Vol.55Issue(4)：34-37,4.DOI:10.19938/j.steelpipe.1001-2311.2026.4.34.37
14MnVNb无缝钢管外折缺陷产生原因分析
Analysis on Causes for Outer Fold Defect of 14MnVNb Seamless Steel Pipe
王辉 1彭杨 1肖国梁 1田汉蒲1
作者信息
- 1. 衡阳华菱钢管有限公司,湖南 衡阳 421001
- 折叠
摘要
Abstract
Addressing the outer fold defect as occurring in the X60Q pipeline steel pipe rolled from the 14MnVNb CC billet,the causes of the defect are identified via relevant analysis,and then improvement measures are proposed.The analysis result shows that the outer fold defect is originated by the surface transverse cracks of the CC billet.And the said cracks are caused by a number of factors,including the nozzle leakage in the moving section of the continuous cast-ing machine,and the high-temperature failure of the sealing ring,which leads to uneven local cooling of the billet and a low temperature of the billet at the inlet of the straightening machine.Accordingly countermeasures are taken,including substituting the nozzle metal sealing ring for the fluorine rubber sealing ring,reducing the secondary cooling specific water rate to 0.15 L/kg and increasing the CCM withdraw speed to 0.30 m/min.As a result the CC billet temperature at the stra-ightening inlet is raised to 882℃,and the ultrasonic testing qualification rate is increased from 81.93%to 93.75%.The above mentioned study reveals the mechanism of influence on the occurrence of the CC billet surface crack by the CC billet temperature at the straightening machine inlet,providing an engineering reference for preventive control of similar outer fold defect of the steel pipe.关键词
无缝钢管/14MnVNb/连铸坯/外折缺陷/横裂纹/拉矫温度Key words
seamless steel tube/14MVNb/CC billet/outer fold defect/transverse crack/straightening machine inlet temperature引用本文复制引用
王辉,彭杨,肖国梁,田汉蒲..14MnVNb无缝钢管外折缺陷产生原因分析[J].钢管,2026,55(4):34-37,4.
