Blow-out (burst bottle)

In the stretch '2079851475616104457 production process, the product exhibits the quality defect of "Blow-out (burst bottle)". The specific manifestation is that the preform ruptures during the stretch blow '2079851475616104453. This defect is relatively common when processing materials such as PET, PP, PC, and its occurrence conditions are usually related to the unreasonable settings of stretching temperature, stretch ratio, blowing pressure, and preform heating uniformity. When the "Blow-out (burst bottle)" situation is severe, it will cause a series of chain quality defects in the product in terms of appearance, dimensional accuracy, mechanical properties, etc., which not only reduces the functionality and safety of the product in use, but also directly increases the scrap rate and production cost. Therefore, this problem requires systematic diagnosis and optimization from multiple dimensions such as material selection, the status of the stretch '2079851475616104457 machine, heating oven, stretch rod, and blow mold, and stretching temperature, stretch ratio, blowing pressure, and preform heating uniformity.

1. Preform temperature too high causing over-stretching. Temperature is the core factor affecting melt fluidity and viscosity. A temperature set too high will cause the melt viscosity to decrease, insufficient melt strength, and even thermal degradation; a temperature that is too low results in poor melt fluidity and insufficient plasticization, making it impossible to fill or form smoothly. A reasonable temperature window should be optimized and determined within the recommended range according to the melting characteristics and thermal stability of the material. 2. Stretching speed too fast. The speed parameter affects the flow state and time allocation of the melt during the forming process. A speed that is too slow causes premature cooling and insufficient filling; a speed that is too fast causes melt fracture, air entrapment, and shear overheating. The optimization of the speed curve should make the melt flow smoothly and orderly in the cavity. 3. Uneven preform wall thickness. The uniformity of wall thickness distribution is directly related to the mechanical properties of the product and the consistency of cooling shrinkage. Excessive wall thickness differences will cause inconsistent cooling rates, with sink marks and warpage in thick-walled areas and insufficient strength in thin-walled areas. Wall thickness design should follow the uniform wall thickness principle, and wall thickness changes should transition smoothly. In terms of equipment maintenance, the regular overhaul and precision confirmation of the stretch '2079851475616104457 machine, heating oven, stretch rod, and blow mold are not in place, causing the actual operating parameters of the equipment to deviate from the process requirements, which will also become a potential inducement of the "Blow-out (burst bottle)" problem.

1. Reduce the preform temperature. Adjustments should follow the principle of gradual progress; the amplitude of each adjustment should not be too large, and it is recommended to decrease by 5%~15% of the current value. After each adjustment, observe the product quality changes stably for at least 5~10 mold cycles, and continue adjusting only after confirming that the improvement direction is correct; avoid one-step excessive adjustment. 2. Reduce the stretching speed. 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, closely monitor changes in key quality indicators, promptly record and feedback the adjustment effect, and form reusable process experience. 3. Improve the preform wall thickness uniformity. Optimization work must be based on an accurate diagnosis of the root cause of the problem, and blind attempts must be avoided. It is recommended to first determine the key influencing factors and their interactions through the process DOE test method or historical production data analysis, and then carry out parameter optimization and structural improvement in a targeted manner to achieve twice the result with half the effort. In terms of material management, incoming inspection of raw materials upon arrival and in-process inspection of work-in-progress should be strengthened, and the key performance indicators of PET, PP, PC should be strictly controlled to ensure the stability of molding quality from the source.

In summary, the causes of the "Blow-out (burst bottle)" problem can be attributed to the combined action of multiple factors such as Preform temperature too high causing over-stretching, Stretching speed too fast. Solving this problem requires starting from aspects such as Reduce the preform temperature, Reduce the stretching speed and adopting systematic governance measures. In actual production, it is recommended to establish a prevention and rapid response mechanism for this problem, and achieve stable production and continuous improvement through preform heating uniformity and biaxial stretch orientation control.