钢管斜连轧工艺参数对轧制力及荒管尺寸精度的影响

Effect of process parameters on rolling force and dimensional precision of tubes rolled by tandem skew rolling process

为分析斜连轧工艺参数对轧制力及荒管尺寸精度的影响,取工艺变参数及范围：顶头前伸量15～28 mm、穿孔段送进角7°～9°、穿孔段孔喉34～35 mm、轧管段轧辊转速182～190 r·min-1,在斜连轧实验机组上对Φ40、Φ42 mm的管坯进行单变量多组实验。结果表明：在实验参数范围内,随顶头前伸量增大,穿孔段轧制力减小,顶头轴向力先减小后增大;随送进角的增大,穿孔段轧制力减小,顶头轴向力微增大;当管坯直径一定时,随孔喉减小,轧制力增大,而当孔喉一定时,随管坯直径增大,轧制力增大。在穿孔段工艺参数一定时,轧管段轧辊速度不同的情况下,若张力轧制时穿孔段及轧管段轧制力均减小,相反若推力轧制时均增大。对斜连轧后荒管的分析结果显示微张力轧制得到的荒管壁厚精度达±0.2 mm,外径精度达±0.35 mm。

To analyze the effect of process parameters on rolling force and dimensional precision of tubes,multigroup univariate experiments were carried out on the TSR test mill for billets with diameters Φ40 and Φ42 mm,and the plug advance from 15 to 28 mm,feed angle from 7° to 9° in the piercing section,rolling gap from 34 to 35 mm in the piercing section,and roll rotation speed from 182 to190 r·min-1 in the rolling section were investigated as the process-related variables. The results show that the rolling force in piercing section decreases with the increase of plug advance,while the axial force of the plug decreases firstly and then increases. The rolling force in piercing section decreases with the increase of feed angle,while the axial force of the plug increases slightly. When the diameter of the billet keeps constant,the rolling force in piercing section increases with the decrease of the rolling gap. And when the rolling gap keeps constant,it increases with the increase of the diameter of the billet. Meanwhile,when the process parameters in piercing section keep constant,the rolling forces in both sections vary in two pattern under different roll rotation speed in rolling section. The rolling forces decrease with tension rolling,while increase with thrust rolling. Under the analysis of the rolled tubes,it is shown that the accuracy of the wall thickness,the diameter of the tube rolled by micro tension rolling are approximately ± 0. 2 mm and ± 0. 35 mm,respectively.