线材减定径机辊环在轧制过程中的应力状态及开裂原因分析

Cause analysis of stress state and cracking of roll ring in Reducing Sizing Mill

针对线材减定径机辊环的使用工艺状况,采用有限元方法分析轧制过程中的应力状态,探讨辊环产生裂纹的原因。减定径机辊环在轧制中的应力状态呈两向压应力和一向拉应力,沿孔槽的等效应力值分布从槽底向槽口逐渐减小,且不同孔型形状和孔型充满率沿孔槽的应力分布变化不同。由于其特有的孔型形状和不同于椭圆孔、圆孔的应力值分布,扁圆孔(Lemon孔)辊环极易产生裂纹甚至开裂。

To investigate the cause of cracking and collapse of roll rings in the actual production,the stress state of roll ring in Reducing Sizing Mill,which was analyzed by the finite element method,consists of two compressive stress in circumferential and radial direction,and one tensile stress in axial direction. Distribution of stress value along the groove of the roll ring during rolling,which presents as decreasing from the bottom to the notch of grooves,varies as different pass shapes and fill ratios. Cracking and even collapsing occur usually on the roll rings with Lemon grooves,due to the oblate shapes and different stress distribution.