【摘要】 随着连铸技术的发展,无缝钢管生产广泛采用水平连铸坯直接穿孔。但是,水平连铸坯的应用,使毛管的内外折缺陷数量也明显增加,其中,又以外折最为严重,以成都某钢管厂为例,外折约占毛管缺陷总量的 93. 3%,年经济损失近 320万元。研究了穿孔调整参数和管坯加热制度对连铸坯毛管外折的影响。适当减小导板距,增大轧辊距,减小穿孔椭圆度;适当提高管坯加热温度和延长加热时间,均能显著减少穿孔毛管的外折缺陷,提高金属收得率。生产实践证明,按照提出的工艺方案,外折数量可减少 40. 75%,经济效益显著。更多还原

【Abstract】 As the technology of continuous casting developing, a lot of billets of horizontal casting are used to pierce directly in production of seamless steel tube .But as well as the applicaton of horizontal continuous casting billets , the amount of disfigurement of pierced shell inner and outer fold is increasing apparently,especially the outer fold is the very seriousone. As the example of a certain tube plant in Chengdu, outer fold took up 93.3% of the amount,and the economic losts is nearly 3 million yuan per year. This paper studies the affection of piercing process factors to the shell’s outer fold of continuous casting billets. It can reduce the pierced shell’s outer fold defects greatly and improve the rate of metal utilization by reducing properly the distance of guiding plate, increasing the distance of roll grinders and reducing the eclipse degree. It can also get the same result by raising the tube billet’s heating temperature and prolonging its heating time. The production practice demonstated that according to the technics project,the outer default can be reduced to 40.75%,the economic benefit are remarkable.更多还原