济钢中厚板质量问题分析及其控制

Analysis of quality problems and quality control of medium plate produced by Jigang

济钢中厚板的主要质量问题是裂纹、探伤不合、钢板分层。裂纹主要与热送有关,探伤不合和钢板分层则与连铸坯的中心质量密切相关。通过降低铸坯中心的偏析和疏松,避免了中心裂纹的产生。实施真空处理和铸坯缓冷,增加轧制道次压下率等措施,有利于提高探伤合格率和降低分层率。

The main quality problems of medium plate produced by Jigang are crack,nonconformity in ultrasonic flaw detection,and plate lamination.Crack defects are mainly related with hot-delivered slab,nonconformity in ultrasonic flaw detection and steel lamination are closed to the center quality of continuous casting slab.In order to solve the problems,a series of measures were taken.They included： reducing the segregation and porosity in central region of slab to avoid center crack,adopting vacuum degasing process and slow cooling of slab,increasing pass reduction rate,etc.These measures are helpful to improving the conformity rate in ultrasonic flaw detection and reducing the lamination rate.