大型厚壁封头热锻成形中降低成型载荷的策略

Strategy of Decreasing Forming Load in Hot Forging of Heavy Thick-wall Sealing Head

大型厚壁封头严苛的使用性能要求其采用整体锻造方法生产,但锻造企业通常不具备足够的设备能力以满足封头整体锻造超高的力能需求。基于刚粘塑性有限元模拟平台DEFORM-3D,对大型厚壁封头上砧旋转锻造成形原有的工艺方案进行了模拟仿真,分析了产生折迭缺陷和锻造载荷超限的原因。优化上砧形状为马鞍型,并确定上砧的运动轨迹为单周压下量为100 mm,每压下一次后上砧旋转角度为24°。对优化后的工艺方案进行仿真计算。结果表明,工艺优化有效地将所需的成形载荷降到了设备能力允许的范围之内,并使整体锻造的封头无折迭缺陷。研究结果对提高封头整体锻造的可行性及改善大型厚壁封头的成形质量具有重要的指导意义。

The forging process for the heavy thick-wall sealing head is required to meet the severe service condition, whereas the forging factories often face with the insufficient forging capacity to execute the forging process. Based on the rigid-viscoplastic FEM platform DEFORM-3D, the upper anvil swaging forging process was simulated to analyze the cause of the fold defect and much higher forming load. The configuration of the upper anvil was optimized in the shape of saddle, meanwhile, the reduction of per revolution was determined as 100 mm and the rotary angle of per reduction of the upper anvil was decided as 24°. The optimized process was numerically simulated. The results show that the forming load to execute the forging process is decreased to available range and the fold is avoided in the finished forgings. The research is very helpful to improve the feasibility of forging process and forming quality of heavy thick-wall sealing head.