Spiral marks on the inner wall of the product

In the extrusion '2079851475616104457 production process, the product exhibits the quality defect of "Spiral marks on the inner wall of the product".The specific manifestation is Spiral texture appears on the inner wall of the product.This defect is more common when processing materials such as HDPE, PP, PVC and PC, and its occurrence is usually related to unreasonable settings of melt temperature, extrusion speed, blowing pressure and mold temperature.When the Spiral marks on the inner wall of the product 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 extruder, head, die, mold clamping mechanism and blowing system, and melt temperature, extrusion speed, blowing pressure and mold temperature.

1. Rotation of the blow pin or rotational disturbance of the airflow.This factor causing the problem reflects that certain process conditions or material properties in extrusion '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. 2. Unstable flow of the parison inner wall.This factor causing the problem reflects that certain process conditions or material properties in extrusion '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. In addition, the insufficient overall coordination of parison wall thickness control and parison temperature uniformity is also a factor that cannot be ignored; there are complex interactions and coupling relationships among the process parameters, and the deviation of any parameter may aggravate the degree of Spiral marks on the inner wall of the product through chain effects. In terms of equipment maintenance, the regular overhaul and accuracy confirmation of the extruder, head, die, mold clamping mechanism and blowing system 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 Spiral marks on the inner wall of the product problem.

1. Check whether the blow pin is loose and rotating.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. 2. Optimize the blow hole structure to make the airflow uniform.Optimization work must be based on accurate diagnosis of the root cause of the problem; blind attempts must be avoided.It is recommended to first determine the key influencing factors and their interactions through process DOE test methods or historical production data analysis, and then carry out targeted parameter optimization and structural improvement to achieve twice the result with half the effort. It is recommended to formulate a preventive checklist for the Spiral marks on the inner wall of the product problem, incorporate parison wall thickness control and parison temperature uniformity into the daily inspection scope, 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 testing of work-in-progress should be strengthened, and key performance indicators of HDPE, PP, PVC and PC should be strictly controlled to ensure the stability of forming quality from the source.

In summary, the causes of the "Spiral marks on the inner wall of the product" problem can be attributed to the combined action of multiple factors such as Rotation of the blow pin or rotational disturbance of the airflow, Unstable flow of the parison inner wall.To solve this problem, it is necessary to start from aspects such as Check whether the blow pin is loose and rotating, Optimize the blow hole structure to make the airflow uniform 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 control and parison temperature uniformity.