排水管作为基础设施，其成型质量直接影响居民的生活，因此对排水管的成型质量要求越来越高。以聚氯乙烯（PVC）建筑排水管为研究对象，以熔体温度、保压压力、模具温度和冷却时间4个因素为试验变量，以排水管的翘曲变形量为响应目标，建立L₉（3⁴）正交试验。结果表明：熔体温度对制件的翘曲变形影响较大，当熔体温度、模具温度、保压压力以及冷却时间分别为180 ℃、60 ℃、70 MPa和10 s时，制件的翘曲变形量相对较小，为2.624 0 mm。通过Moldflow模流分析软件对优化后的工艺参数进行验证，结果达到实际生产要求。

Drainage pipes, as infrastructure, have a direct impact on the quality of residents' lives due to their molding quality, which is why the requirements for the molding quality of drainage pipes are becoming increasingly stringent. Taking polyvinyl chloride (PVC) building drainage pipes as the research subject, and considering the melt temperature, holding pressure, mold temperature, and cooling time as four experimental variables, with the warpage deformation of the drainage pipe as the response target, an L₉(3⁴) orthogonal test was established. The results indicated that the melt temperature had a significant effect on the warpage deformation of the part. When the melt temperature, mold temperature, holding pressure, and cooling time were set at 180°C, 60°C, 70 MPa and 10 s, respectively, the warpage deformation of the part was relatively small, at 2.624 0 mm. The optimized process parameters were verified using Moldflow mold flow analysis software, and the results met the actual production requirements.