Star-shaped cracks at the bottom of the product after deep drawing

In the '2079851475616104458 (vacuum forming) production process, the product exhibits the quality defect of "Star-shaped cracks at the bottom of the product after deep drawing".The specific manifestation is Star-shaped radial cracks appear at the bottom of the product.This defect is more common when processing materials such as PP, PS, PET, PVC and ABS sheets, and its occurrence is usually related to unreasonable settings of sheet heating temperature, forming pressure/vacuum, mold temperature and cooling time.When the Star-shaped cracks at the bottom of the product after deep drawing 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 '2079851475616104458 machine, heating oven, mold and vacuum/air pressure system, and sheet heating temperature, forming pressure/vacuum, mold temperature and cooling time.

1. Excessive stretching at the bottom center.This factor causing the problem reflects that certain process conditions or material properties in '2079851475616104458 (vacuum forming) 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. Local defects in the sheet.This factor causing the problem reflects that certain process conditions or material properties in '2079851475616104458 (vacuum forming) 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 sheet heating uniformity and stretch ratio control 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 Star-shaped cracks at the bottom of the product after deep drawing through chain effects. In terms of equipment maintenance, the regular overhaul and accuracy confirmation of the '2079851475616104458 machine, heating oven, mold and vacuum/air pressure 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 Star-shaped cracks at the bottom of the product after deep drawing problem.

1. Reduce the bottom stretch ratio.Adjustments should follow the principle of gradual progress; each adjustment should not be too large, and a decrement of 5%~15% of the current value is recommended.After each adjustment, stably observe the product quality changes for at least 5~10 mold cycles, and continue adjusting only after confirming the improvement direction is correct; never make excessive one-step adjustments. 2. Use plug pre-stretching.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. 3. Check sheet quality.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 PP, PS, PET, PVC and ABS sheets should be strictly controlled to ensure the stability of forming quality from the source.

In summary, the causes of the "Star-shaped cracks at the bottom of the product after deep drawing" problem can be attributed to the combined action of multiple factors such as Excessive stretching at the bottom center, Local defects in the sheet.To solve this problem, it is necessary to start from aspects such as Reduce the bottom stretch ratio, Use plug pre-stretching 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 sheet heating uniformity and stretch ratio control.