Poor venting of the blow mold

During the injection '2079851475616104457 production process, the product exhibits the quality defect of "Poor venting of the blow mold". Specifically manifested as the air in the mold cavity being unable to be discharged during '2079851475616104457. This defect is relatively common when processing materials such as PET, PP, HDPE, and PS, and its occurrence conditions are usually related to unreasonable settings of injection pressure, parison temperature, blowing air pressure, and mold temperature. When the Poor venting of the blow mold situation is severe, it will cause a series of chain-reaction quality defects in the product in terms of appearance, dimensional accuracy, mechanical properties, etc., which not only reduces the usability and safety of the product, but also directly increases the scrap rate and production cost. Therefore, this problem requires systematic diagnosis and optimization from multiple dimensions, including material selection, the condition of the injection '2079851475616104457 machine, core rod, parison mold, blow mold, and transfer mechanism, as well as injection pressure, parison temperature, blowing air pressure, and mold temperature.

1. Vent holes or vent grooves clogged or insufficient in number. Mold venting is a basic condition to ensure smooth filling of the melt. When venting is poor, the air in the mold cavity is compressed to form a high-pressure air cushion, which hinders melt flow and causes problems such as insufficient filling, burnt, and weld lines. A reasonable venting design should consider the venting position and venting gap to ensure that air is discharged in time. In addition, insufficient overall coordination between parison wall thickness uniformity and transfer temperature control is also a factor that cannot be ignored; there are complex interactions and coupling relationships among the various process parameters, and the deviation of any single parameter may aggravate the degree of Poor venting of the blow mold through chain effects.

1. Clean the vent holes. Cleaning work should be incorporated into the equipment preventive maintenance plan, and the cleaning frequency should be reasonably determined according to the actual conditions of the processed material and the operating cycle. Use dedicated cleaning tools and cleaning materials to avoid scratching the cavity surface or electrolytic corrosion caused by improper operation. After cleaning, re-check and confirm that the key clearances are accurate. 2. Add vent grooves or use porous metal venting inserts. The installation of equipment or accessories should strictly follow the installation manual; the key mating surfaces must be cleaned and checked for damage before installation. Fastening bolts should be tightened evenly according to the specified torque values and diagonal sequence; after installation, use precision measuring tools to verify whether the installation accuracy meets the technical requirements. It is recommended to formulate a preventive checklist for the Poor venting of the blow mold problem, incorporate parison wall thickness uniformity and transfer temperature control into the scope of daily inspections, and conduct online monitoring of key parameters through the SPC statistical process control method to achieve early warning and rapid response to problems. In terms of material management, incoming inspection of raw materials and in-process inspection of work-in-progress should be strengthened, and the key performance indicators of PET, PP, HDPE, and PS should be strictly controlled to ensure the stability of molding quality from the source.

In summary, the causes of the "Poor venting of the blow mold" problem can be attributed to the combined action of multiple factors such as vent holes or vent grooves clogged or insufficient in number. Solving this problem requires starting from aspects such as clean the vent holes and add vent grooves or use porous metal venting inserts, and adopting systematic governance measures. In actual production, it is recommended to establish a prevention and rapid response mechanism for this problem, achieving stable production and continuous improvement through parison wall thickness uniformity and transfer temperature control.