- POSSIBLE CAUSES: Hold up particle
- SOLUTIONS: Change screen pack. Check Row Material Moisture. Check heat stability of master batch.
2. GELES, HARD OR UNPLASTICIZED PROFILE
- POSSIBLE CAUSES: Improper back pressure. Improper temp gradient. Moister in master batch.
- SOLUTIONS: Change temp. Profile. Use fine wire mesh. Reduce die lip opening. Reduce adaptor flow area. Change screw geometry. Pre-dry master batch.
- POSSIBLE CAUSES: Extruder surging. Film thickness variation across width. Spacer thickness variation. Improper drive Performance.
- SOLUTIONS: Refer problem III in general extrusion processing. Reduce throughput rate. Increase die volume. Adjust die lip. Check uniformity of die temp. Check spacer thickness. Use carbon steel blade. Check drive performance. Check temperature of orientation unit across width. Check flow velocity of hot air across width.
- POSSIBLE CAUSES: Excessive stretch ratio. Low orientation temp. Hold up particle in film. Very stiff film. Extruder surging
- SOLUTIONS: Increase stretch ratio. Increase orientation temperature. Refer problem of film puncture and gels, hard or unplasticized particles. Increase distance between die opening and water levels in tank.
5. LOW TENACITY / HIGHER ELONGATION
- POSSIBLE CAUSES: Low stretch ratio. Too soft film. Low orientation temp
- SOLUTIONS: Increase stretch ratio. Increase distance between die opening and water level in quenching tank. Increase orientation temp.
- POSSIBLE CAUSES: Tape too stiff Scratches on tape moving path.
- SOLUTIONS: Use anti fabrillation MB. Polish tape moving path. Use wear resistance material items.
7. SHRINKAGE IN FABRIC / CURVED TAPE
- POSSIBLE CAUSES: Residual stress in tape.
- SOLUTIONS: Check annealing system. Increase annealing temp. Check cooling efficiency of roller.
Mob/Whatsapp: (+ 84) 968737841
NHAT HUY GROUP - Leading manufacturer of PP Filler for PP woven from Vietnam
8th Floor, Han Viet Tower, 203 Minh Khai, Hanoi, Vietnam
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