2Cr13合金管热轧穿孔工艺探讨

Discussion on Hot-piercing Process for 2Cr13 Alloy Steel Pipe

介绍2Cr13合金管热轧穿孔内螺纹的形成原因,分析增大顶头均壁段锥角的利弊,并优化其热轧穿孔工艺参数。分析认为:热轧生产2Cr13合金钢管的穿孔参数调整,一次咬入位置和二次咬入位置距离应控制在不超过2.2个螺距,同时顶前压下率在6.5%以内为宜;一旦出现异常停机,及时将管坯退回加热区加热,即使出现前卡,也要谨慎调整辊距,以微调顶头前伸量作为首要调整方式;合理的工模具设计直接决定着后期产品的质量和生产效率;2Cr13产品实现了多次批量化的生产实践表明合金元素含量14%~16%的高合金钢产品可以通过热轧生产方式生产。

Reasons for the inner spiral defect of the 2Cr13 alloy steel pipe as occurring during the hot-piercing process are described here in the essay.The advantages and disadvantages as brought about by increasing the taper of the plug reeling section are analyzed,and the hot-piercing process parameters are optimized.The analysis leads to the conclu-sion which covers the following aspects.The piercing parameters need to be properly adjusted,i.e.,the distance between the first bite position and the secondary one should be controlled as less than 2.2 pitches,and the pre-piercing screwdown rate should be controlled within 6.5%.Once the mill is accidentally stopped,the billet must be promptly withdrawn into the heating area for reheating.Even in case of front-end sticking,the roll space has to be carefully adjusted,taking the method of trimming the plug front-extending amount as the prior adjustment measure.Proper design of the molds/dies will directly determine quality and production efficiency of the follow-up products.The practice of numerous massive produc-tions of the serial 2Cr13 products demonstrates that the pipes in high-alloy steel as containing 14%~16%alloy elements can be produced by means of the hot-rolling manufacturing process.