辗扩参数对大型厚壁筒形件变形规律的影响

The Influence of Rolling Process Parameters on Strain Penetration of Heavy Thick-wall Cylindrical Parts

采用数值模拟的方法,建立了大型厚壁筒形件辗扩工艺模型,分析了辊系尺寸、筒形件尺寸和芯辊进给速度对∅712 mm/308 mm×902 mm筒件辗扩接触弧长和变形区应变分布规律的影响。结果表明,驱动辊半径为500 mm,芯辊半径为130 mm,筒形件内半径为164 mm(壁厚192 mm)时,筒件局部加载时的内外接触弧长之比最小,变形区应变分布的对称性好,变形穿透壁厚所需的压下量最小。驱动辊和芯辊半径分别为500 mm和130 mm条件下,芯辊进给速度为1.5 mm/s时,整个连续辗扩过程中筒件发生壁厚方向均匀的整体变形。辗扩结束后,筒形件中部大部分区域的应变平均值达到1.69.

The ring rolling model of thick-wall cylindrical parts was established by numerical simulation method.The influence of the size of rollers and cylindrical-parts,feeding velocities on contact arc lengths and strain distributions were simulated and analyzed.The results indicates that the minimum contact arc length,symmetrical strain distributions along thickness and the minimum reduction for strain penetration can be obtained in the local loading region with the 500 mm-radius driving roller,the 130 mm-radius idle roller and the 164 mm inner radius(192 mm wall thickness)cylindrical-part.When the feeding velocity was 1.5 mm/s,strain penetration can be met during the whole rolling process with the 500 mm-radius driving roller and the and the 130 mm-radius idle roller.Meanwhile,the uniform deformation occurred along the thickness of the cylindrical part,and the average equivalent strain was 1.69 at the most regions in the cylinder wall.