Traceability and quality improvement of Forming Defects in glass packaging bottles

Glass bottles are widely used in the fields of food, daily chemicals and medicine, with strict requirements for both appearance and internal quality. Defects such as bubbles, scratches and pockmarks not only affect the appearance, but also reduce the thermal shock resistance and pressure resistance performance. The thermal shock threshold of containers with crack defects can be reduced to 50% of that of intact bottles. Bubbles mostly occur during the melting stage. Excessive moisture content of raw materials, poor uniformity of compound materials, and unstable atmosphere in the kiln can cause residual gases such as CO₂ and SO₂ in the glass liquid. The erosion and shedding of refractory materials, as well as the presence of impurities in broken glass, can also form bubble nuclei. Research shows that when the clarification temperature is below 1450℃ and the insulation is insufficient, the residual bubble rate increases by 3 to 5 times. Surface scratches and pockmarks mainly come from the molding process. The material droplets fall eccentrically and rub against the mold wall, causing scratches. If the surface wear and roughness of the mold exceed the standard, it will replicate to the bottle body and cause a pitted surface. When the temperature difference between the initial mold and the final mold exceeds 30℃, cold spots and texture defects increase significantly, and the smoothness decreases. The mismatch of process parameters exacerbates defects. Excessive cutting marks from the feeding machine, unstable blowing pressure, and mismatch between the machine speed and the cooling rhythm can all cause surface defects. Data shows that the machine speed fluctuates by more than ±5 units, and the rate of uneven thickness and spot defects increases by approximately 8%. To enhance quality, it is necessary to implement full-process control: strengthen the screening of raw materials and the purification of broken glass, and strictly control the moisture content; Optimize the temperature control of the kiln and the clarification process to ensure the homogenization of the glass liquid. Improve the processing accuracy and surface hardness of molds, and carry out regular maintenance. Precisely match the blanking, machine speed, air pressure and cooling parameters to stabilize the forming temperature field. After optimization, the defect rate of a certain enterprise dropped from 6.2% to 1.5%, and its production efficiency increased by 12%.