In the production process of plastic bottles, blow molding molds play a crucial role. However, due to improper operation, improper mold design or maintenance, some problems may occur during the use of blow molding molds. This article will analyze common problems with bottle blowing molds and provide corresponding solutions. At the same time, we will introduce professional guidance from HeYan Mold to help you better solve production problems.
1, Transition issues
Problem description: The transition problem mainly manifests in the change of bottle wall thickness from thick to thin, such as the thickness change from shoulder to middle or from bottom to middle. This may lead to issues such as incomplete bottom shaping and suboptimal contour of petal base.
Solution:
Check if the high-pressure filter on the side of the mold is unobstructed to ensure normal supply of high-pressure air.
Check the operation of the circuit valve to ensure accurate positioning during blowing.
Check the airflow control components for blowing air to ensure that the set values are correct and there are no internal blockages.
Ensure that the blowing process is completed as quickly as possible to avoid additional cooling of the PET material.
Keep all ventilation holes on the mold unobstructed.
Heyan Mold Tip: In response to transition issues, Heyan Mold recommends that customers regularly maintain and inspect the mold to ensure smooth operation of all components. At the same time, we provide professional mold design and optimization services to help customers solve transition problems and improve product quality.
2, Swelling of bottle mouth, blowing of bottle and gas leakage
Problem description: The screw area at the bottle mouth expands and conducts to the anti air groove. It is more severe when the weather is hot, and may be accompanied by a sound of air leakage.
Solution:
Adjust the position of the cooling plate and strengthen the protection of the thread area of the preform.
Using external cooling method to control the temperature of the thread area of the preform and the core rod.
Optimize the design of the cooling plate to improve the cooling effect.
Heyan Mold Tip: In response to issues such as bottle mouth expansion and gas leakage during bottle blowing, Heyan Mold recommends that customers pay attention to controlling the oven temperature and the conveying speed of bottle preforms to avoid overheating during heating. At the same time, we provide customized cooling system design solutions to help customers solve temperature control problems.
3, Neck curvature
Problem description: The protruding ring under the thread of the bottle mouth is displaced and not perpendicular to the centerline of the bottle body.
Solution:
Adjust the thickness of the material accumulation at the neck of the bottle to avoid deformation during mold closing.
Check the clamping condition of the convex ring on the top plate of the bottle blowing mold to ensure sufficient thermal clearance.
Correct the position of the conveying arm and the blowing center.
Heyan Mold Tip: Heyan Mold pays special attention to the accuracy and stability of bottleneck parts in the mold design and manufacturing process. We use advanced processing technology and high-quality materials to ensure the accuracy and durability of the mold, effectively avoiding the occurrence of neck bending problems.
4, Bottom line turns blue
Problem description: Pearlescent stripes appear along the bottom cutting line, and this area of the defective bottle is relatively thin.
Solution:
Adjust the mold design to ensure thicker material on the cross-section of the area.
Control the heating and cooling process to avoid excessive cooling or heating.
Heyan Mold Tip: To address the issue of blue bottom line, Heyan Mold recommends that customers optimize the heating and cooling system settings to ensure even heating and moderate cooling speed of the preform during the molding process. At the same time, we provide professional mold design and optimization services to help customers solve such problems.
5, Bottom damage
Problem description: There are often slight cracks at the bottom where the material accumulation is too thick, which may cause bursting during filling.
Solution:
Control the temperature at the end of the preform to avoid overcooling or overheating.
Adjust the gap between the stretching rod and the bottom of the mold to ensure accurate positioning.
Heyan Mold Tip: Heyan Mold pays attention to precise control of the gap between the stretching rod and the mold bottom during the mold design and manufacturing process. We use advanced processing technology and precision measuring equipment to ensure the accuracy and stability of the mold, effectively avoiding the occurrence of bottom damage problems.
6, The screw part of the bottle mouth is damaged
Problem description: The exhaust groove in the threaded area is subjected to undue tension.
Solution:
Ensure that the adjustment of the conveying arm is precise and error free.
Check the alignment of the blowing core and mold.
Control the temperature of the thread area of the preform to avoid overheating.
Heyan Mold Tip: In response to the issue of damaged screw parts at the bottle mouth, Heyan Mold recommends that customers pay attention to the adjustment accuracy of the conveying arm and blowing core, as well as temperature control in the thread area of the bottle preform. We provide professional mold debugging and maintenance services to help customers solve such problems, improve production efficiency and product quality. "
