Processing Machinery
7 조회수
HDPE film bubble instability (spiral swing)
문제 현상
The film bubble swings in a spiral shape, the frost line fluctuates, and the film thickness changes periodically.
원인 분석
Low melt strength, spiral disturbance of the air ring airflow, too low frost line or excessive die lip shear heat can all induce spiral film bubble instability.; when troubleshooting on site, verify item by item according to this mechanism, and avoid blindly adjusting the machine based only on experience
해결 방법
①Switch to a high molecular weight low melt index formulation; ②open the air vent wider or reduce the air volume to weaken the airflow impact; ③raise the frost line height; ④widen the die gap to reduce shear heat.
핵심 요약
Spiral swing is a comprehensive problem of melt strength and airflow stability; the formulation and air ring are adjusted in both directions, and the effect is judged by a stable frost line.; after confirming effectiveness, solidify the parameters and practices into the work instruction to prevent recurrence
이 정보가 도움이 되었나요?
0 명이 도움이 되었다고 합니다
의견 주셔서 감사합니다!