高压配电盒设计开发中，安装面的平面度直接影响安装精度、抗疲劳性能以及密封性能。针对某高压配电盒在初始工艺下安装面平面度不合格的问题，采用计算机辅助工程技术对其注塑成型过程进行模拟，并设计正交试验探究平面度的工艺优化方案。结果表明：保压时间对平面度的影响程度为极显著，料筒温度和模具表面温度对平面度的影响程度为显著，注射时间对平面度的影响程度为不显著。最优工艺参数组合为A₂B₃C₁D₃。优化工艺模拟验证结果显示：平面度由初始工艺的2.756 9 mm下降为1.532 9 mm，优化率达到44.4%，满足设计要求。充填过程、缩痕、熔接线及注射压力结果也均满足要求。采用优化工艺进行试模，样品外观及平面度合格，验证了此优化工艺的可行性。

In the design and development of high voltage distribution box, the flatness of installation surface directly affects the installation accuracy, anti-fatigue performance and sealing performance. Aiming at the problem that the flatness of the installation surface of a high voltage distribution box is unqualified under the initial process, the injection molding process was simulated by computer aided engineering technology, and the orthogonal test was designed to explore the process optimization scheme of flatness. The results show that the influence of holding time on flatness is extremely significant, the influence of barrel temperature and mold surface temperature on flatness is significant, and the influence of injection time on flatness is not significant. The optimum combination of process parameters is A₂B₃C₁D₃. The simulation results of the optimized process show that the flatness is reduced from 2.756 9 mm to 1.532 9 mm, and the optimization rate reaches 44.4%, which meets the design requirements. The filling process, shrinkage mark, welding line and injection pressure results also meet the requirements. The appearance and flatness of the samples are qualified by the optimized process, which verifies the feasibility of the optimized process.