Irregular color spots on the parison surface

In the injection '2079851475616104457 production process, the product exhibits the quality defect of "Irregular color spots on the parison surface".The specific manifestation is Uneven color spots or color differences appear on the parison surface.This defect is more common when processing materials such as PET, PP, HDPE and PS, and its occurrence is usually related to unreasonable settings of injection pressure, parison temperature, blowing pressure and mold temperature.When the Irregular color spots on the parison surface situation is severe, it will cause a series of chain quality defects in the product's appearance, dimensional accuracy, mechanical properties and other aspects, which not only reduces the product's functionality and safety 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 injection '2079851475616104457 machine, core rod, parison mold, blow mold and transfer mechanism, and injection pressure, parison temperature, blowing pressure and mold temperature.

1. Uneven dispersion of color masterbatch.Uniformity runs through all stages of the forming process.Uneven temperature, uneven pressure distribution, uneven cooling and uneven material mixing all lead to discreteness in product quality.Ensuring the uniform distribution of physical quantities is a prerequisite for obtaining products with good consistency and stable quality. 2. Insufficient screw mixing capability.This factor causing the problem reflects that certain process conditions or material properties in injection '2079851475616104457 do not meet the optimal forming requirements.Such problems are often cumulative and concealed, and should be investigated and verified as key focus items during process debugging and finalization to ensure hidden dangers are eliminated at the source. 3. Batch differences of raw materials.Material selection and handling are the foundation of forming quality.The intrinsic properties of the resin such as molecular weight, molecular weight distribution and melt index determine its processing window and final performance.Factors such as excessive moisture content of raw materials, mixed impurities and improper regrind ratios will all cause various defects during processing. In terms of equipment maintenance, the regular overhaul and accuracy confirmation of the injection '2079851475616104457 machine, core rod, parison mold, blow mold and transfer mechanism are not in place, causing the actual operating parameters of the equipment to deviate from process requirements, which will also become a potential inducement of the Irregular color spots on the parison surface problem.

1. Use color masterbatch with good dispersibility.Before introducing new tools, new materials or new methods, sufficient applicability evaluation and small-batch verification should be carried out.It is recommended to first conduct offline tests or simulation analyses outside production conditions, and introduce them into the formal production line only after confirming effectiveness and safety.Keep proper change management records to facilitate subsequent traceability and experience accumulation. 2. Improve the capability of the screw mixing section.When implementing adjustments, it is recommended to use the single-factor variable method, adjusting only one parameter at a time and fully evaluating the effect, to avoid simultaneous changes of multiple parameters making the cause of the problem untraceable.The adjustment amplitude 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. 3. Check the batch consistency of raw materials.Inspection work should establish a standardized checklist, specifying inspection items, technical standards, inspection frequency and responsible persons.Key equipment components should be regularly disassembled to check the condition of hidden parts, and judgment should not be based solely on operating appearance.Inspection results should be recorded in detail and a trend analysis mechanism established to predict potential failures. In terms of material management, incoming inspection of raw materials and in-process testing of work-in-progress should be strengthened, and key performance indicators of PET, PP, HDPE and PS should be strictly controlled to ensure the stability of forming quality from the source.

In summary, the causes of the "Irregular color spots on the parison surface" problem can be attributed to the combined action of multiple factors such as Uneven dispersion of color masterbatch, Insufficient screw mixing capability.To solve this problem, it is necessary to start from aspects such as Use color masterbatch with good dispersibility, Improve the capability of the screw mixing section and take 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.