Trimming (punch cutting) burrs

In the '2079851475616104458 (vacuum forming) production process, the product exhibits the quality defect of "Trimming (punch cutting) burrs". The specific manifestation is that burrs appear at the trimmed edge of the product. This defect is relatively common when processing materials such as PP, PS, PET, PVC, ABS sheets, and its occurrence conditions are usually related to the unreasonable settings of sheet heating temperature, forming pressure/vacuum level, mold temperature, and cooling time. When the "Trimming (punch cutting) burrs" 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 '2079851475616104458 machine, heating oven, mold, and vacuum/air pressure system, and sheet heating temperature, forming pressure/vacuum level, mold temperature, and cooling time.

1. Cutting knife wear. Mechanical wear and looseness during long-term equipment operation will cause clearance changes, precision decline, and unstable operation, thereby causing various process and quality problems. Establishing a regular inspection and preventive maintenance system for equipment operating status and promptly repairing or replacing worn parts is a necessary measure to maintain equipment precision and process stability. 2. Improper cutting knife clearance. This factor causing the problem reflects that certain process conditions or material characteristics in '2079851475616104458 (vacuum forming) processing have not met the optimal molding requirements. Such problems are often cumulative and hidden, and should be investigated and verified as key focus items during process debugging and finalization to ensure that hidden dangers are eliminated at the source. 3. Insufficient punching pressure. Pressure directly determines the filling ability of the melt during the forming process and the effect of conforming to the mold. Insufficient pressure results in incomplete filling and poor replication accuracy; excessive pressure may cause secondary defects such as flash and excessive internal stress. The pressure setting should comprehensively consider factors such as material viscosity, product dimensions, and mold structure. In terms of equipment maintenance, the regular overhaul and precision 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 the process requirements, which will also become a potential inducement of the "Trimming (punch cutting) burrs" problem.

1. Replace or regrind the cutting knife. When replacing parts, original factory spare parts of the same or higher specifications should be selected to ensure that the installation accuracy and fitting tolerances meet the equipment technical requirements. After replacement, relevant parameters need to be recalibrated and trial runs performed to verify the effect; normal production can only be resumed after confirming that expectations are met. It is recommended to establish a spare parts life cycle management ledger. 2. Adjust the clearance. 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. 3. Increase the punching pressure. When implementing adjustments, it is recommended to adopt 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. 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 PP, PS, PET, PVC, ABS sheets should be strictly controlled to ensure the stability of molding quality from the source.

In summary, the causes of the "Trimming (punch cutting) burrs" problem can be attributed to the combined action of multiple factors such as Cutting knife wear, Improper cutting knife clearance. Solving this problem requires starting from aspects such as Replace or regrind the cutting knife, Adjust the clearance 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 sheet heating uniformity and stretch ratio control.