Dalian Youyan Plastic Machinery Co., Ltd.
Couplet: Feng Manager
Phone/fax:086-0411-86260347
Hand:18624289888
13604263838
Mail box:21272059@qq.com
Network access:www.dlyouyan.com
Address: Chinese Lushunkou District of Dalian City, the three streams town (take Tuchengzi Dalian to Lushun Road westbound vehicle airport about 200 meters in front of about 100 meters)
Three-layer Co-extrusion Blown Film Machine: Common Faults & Solutions
This core composite film production equipment often malfunctions due to raw material properties, process parameters and component conditions. Common faults, causes and remedies are listed below.
1. Unstable Bubble Swing & Offset
**Causes**
Uneven air ring airflow, fluctuating extrusion temperature, inconsistent raw material melting, ambient air disturbance, unstable haul-off speed.
**Solutions**
Clean and repair air ring for even wind speed; calibrate temperature control within ±2℃; dry materials to moisture content below 0.1% and stabilize screw speed; seal workshop and install wind shields; inspect haul-off motor and frequency converter.
2. Uneven Film Thickness
**Causes**
Improper die gap, uneven die temperature, mismatched fluidity of three-layer materials, fluctuating winding tension.
**Solutions**
Adjust die gap deviation under 0.05mm; replace defective heating rings; adopt materials with similar melt index; calibrate tension controller.
3. Film Holes & Tearing
**Causes**
Impure raw materials, insufficient bubble cooling, die buildup and scratches, excessive haul-off tension.
**Solutions**
Replace filter screen regularly; boost air volume and raise cooling line height; clean carbon deposits and polish die surface; reduce tension within safe stretching limit.
4. Surface Crystal Spots & Fish Eyes
**Causes**
Undried materials, carbon deposits inside screw and die, excessive recycled cross-linked materials.
**Solutions**
Dry materials at specified temperature and duration; clean internal residue with purging compound; limit recycled material proportion below 30%.
5. Insufficient & Fluctuating Extrusion Output
**Causes**
Worn screw, blocked hopper, clogged filter, inadequate melting temperature.
**Solutions**
Replace severely worn screw; clear hopper blockage and equip vibratory feeder; change screen when pressure difference exceeds 0.5MPa; raise extrusion temperature properly.
6. Irregular Winding
**Causes**
Asynchronized haul-off and winding speed, misaligned winding shaft, uneven lateral tension.
**Solutions**
Tune speed matching ratio; calibrate shaft parallelism; balance edge and middle film tension.
Daily Preventive Measures
Regularly clean screw, die and air ring; strictly screen raw materials; archive process data and fault records; periodically inspect and replace vulnerable parts.
The above measures effectively fix common faults, improving film quality and production efficiency.
