Container bottle neck deformation (material overflow)

During the extrusion '2079851475616104457 production process, the product exhibits the quality defect of "Container bottle neck deformation (material overflow)". Specifically manifested as deformation of the bottle neck area or overflow flash appearing. This defect is relatively common when processing materials such as HDPE, PP, PVC, and PC, and its occurrence conditions are usually related to unreasonable settings of melt temperature, extrusion speed, blowing air pressure, and mold temperature. When the Container bottle neck deformation (material overflow) 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 extruder, die head, die, mold clamping mechanism, and blowing system, as well as melt temperature, extrusion speed, blowing air pressure, and mold temperature.

1. Poor alignment between the blow rod and the die. This factor leading to the problem reflects that certain process conditions or material properties in extrusion blow '2079851475616104453ing have not met the optimal molding requirements. Such problems often have cumulative and hidden characteristics, and should be investigated and verified as key focus items during process debugging and finalization to ensure that hidden dangers are eliminated from the source. 2. Temperature at the bottle neck area too high. Temperature is the core factor affecting melt fluidity and viscosity. Setting the temperature too high will cause the melt viscosity to decrease, insufficient melt strength, and even thermal degradation; if the temperature is too low, the melt fluidity is poor and plasticization is insufficient, making it impossible to fill or mold smoothly. A reasonable temperature window should be optimally determined within the recommended range according to the melting characteristics and thermal stability of the material. 3. Insufficient mold clamping force. This factor leading to the problem reflects that certain process conditions or material properties in extrusion blow '2079851475616104453ing have not met the optimal molding requirements. Such problems often have cumulative and hidden characteristics, and should be investigated and verified as key focus items during process debugging and finalization to ensure that hidden dangers are eliminated from the source. In terms of equipment maintenance, inadequate regular overhaul and accuracy confirmation of the extruder, die head, die, mold clamping mechanism, and blowing system cause the actual operating parameters of the equipment to deviate from the process requirements, which can also become a potential inducement of the Container bottle neck deformation (material overflow) problem.

1. Calibrate the blow rod position. Calibration work should use standard instruments that have been verified as qualified by legal metrological verification institutions, and be carried out strictly in accordance with the specified cycle and method. The calibration results should form a written technical report, giving the deviation value and expanded uncertainty. Out-of-tolerance equipment should be immediately taken out of service and marked for repair, and can only be restored to use after passing recalibration. 2. Strengthen cooling of the bottle neck area. Before implementing this measure, its feasibility and expected effect should be fully evaluated, and the details of the plan should be communicated and confirmed with relevant technical personnel; during implementation, changes in key quality indicators should be closely monitored, and the adjustment effect should be recorded and fed back in a timely manner to form reusable process experience. 3. Increase the mold clamping force. When implementing adjustments, it is recommended to adopt the single-factor variable method, adjusting only one parameter at a time and fully evaluating the effect, to avoid multiple parameters changing simultaneously making the cause of the problem untraceable. The adjustment magnitude should be small rather than large; each adjustment is recommended to be controlled within 5%~10% of the original value, and after adjustment, run stably for at least 3~5 mold cycles to observe the effect. 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 HDPE, PP, PVC, and PC should be strictly controlled to ensure the stability of molding quality from the source.

In summary, the causes of the "Container bottle neck deformation (material overflow)" problem can be attributed to the combined action of multiple factors such as poor alignment between the blow rod and the die and temperature at the bottle neck area too high. Solving this problem requires starting from aspects such as calibrate the blow rod position and strengthen cooling of the bottle neck area, 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 control and parison temperature uniformity.