目的 完成塑料薄膜在包裹丝饼前的焊接工作。方法 设计一种超声波封膜系统， 阐述系统结构及工作原理， 并分析塑料薄膜焊接质量的影响因素。结果 针对化纤行业的特殊使用环境， 结合了理论分析， 确定了系统的焊接条件。结论 该系统经实际应用， 运转良好， 具有推广价值。

This study was aimed to finish the welding work of the plastic film before packing spindle. An ultrasonic film-sealing system was designed, the structure and working principle of which were described, and the influencing factors of the welding quality for plastic film were analyzed. Considering the special environment of chemical fiber industry, combining theoretical analysis, the welding conditions of the system were determined. The system worked well in practical application, and is worth promoting.