Assel轧机轧制薄壁管壁厚螺旋性不均研究

Study on spiral wall thickness unevenness of thin-walled tubes rolled by Assel rolling mill

针对Assel轧管机轧制薄壁管时出现内螺纹缺陷问题,采用三维有限元分析软件Simufact,对X20Cr13钢管典型规格160mm×6.5mm Assel斜轧过程进行数值模拟。研究了不同芯棒运动方式、送进角及轧辊辗轧带线型对斜轧后荒管内螺纹深度的影响。结果表明：全浮动芯棒轧后荒管所产生的内螺纹深度最小,固定芯棒次之,拉力芯棒最差;随着送进角逐渐增大,轧后荒管的内螺纹深度逐渐加深;双曲线型辗轧带更有利于控制轧后荒管的内螺纹深度,双曲线辗轧带条件下,轧件在轧制过程中所产生的扭转变形量要较直线型辗轧带小大约35%。

In view of the internal thread defect of thin-walled tubes rolled by Assel 3-roll skew rolling mill,Assel cross-rolling process of X20 Cr13 steel tube with typical specification of160 mm×6.5 mm was numerically simulated by using 3 Dfinite element analysis software Simufact.The influences of different mandrel movement modes,feeding angles and rolling strip profiles on the depth of internal thread were studied.The results show that the depth of the internal thread of steel tube rolled by the full floating mandrel is the most shallow,the second is that of the fixed mandrel and that of the pull mandrel is worst,and it will be gradually deepened when the feed angle increases;the hyperbolic rolling strip is more conducive to controlling the internal thread depth of the rolled tube.Under the condition of hyperbolic rolling strip,the amount of twist deformation of the rolled tube in the rolling process is about 35% smaller than that of the straight rolling strip.