• by MEOT
• visits
• 2024/3/19

Common problems with preform molds

1. Bottle mouth flash refers to a thin layer of material forming a bulge at the bottle mouth thread or at the mold closure. Generally, mold wear causes inaccurate mold closing, resulting in excessive material injection and flashing.

2. Poor preform mold closing includes poor preform mold closing and blow molding poor closing. The cause is similar to bottle mouth flash, which is caused by mold wear.

3. There is remaining material on the shoulder of the bottle, and a ring is embedded there. The cause is generally caused by uneven heating and rotation and uneven stretching of materials during blow molding.

4. There are impurities, black spots, foreign matter, unmelted particles, etc. in the bottle. The cause is usually a problem with the material processing before injection molding. For example, a clean mold will cause black spots on the bottle, impure material particles will cause the presence of foreign matter and incomplete melting, and the failure of the filter at the mouth of the central distributor will cause incompletely plasticized particles to enter the mold cavity, thereby causing the inside of the bottle to There are unablated particles.