The principle, method and tool to determine the fluidity of thermoplastics using Archimedean spiral method are introduced. In addition, the factors influencing injection molding coefficient are introduced, which can provide practical process with reference as well. 主要介绍阿基米德螺旋线法测定热塑性塑料流动性能的原理、测定方法和工具,对注射成型系数的影响因素进行了探讨,可供指导生产实践参考。