I. Case Study: Deformation Adjustment of 2-Cavity Automotive Structural Parts Made of PC + 20%GF Hot Runner
Initial Fault State: The product's length is 120mm, its width is 64mm, and it has a two-point hot runner gate. The maximum product deformation is approximately 2mm, and the yield is less than 60%. The target was not met, and repeated adjustments required over 4 hours.
Steps for Rapid Adjustment:
Initially, rectify the internal insert steel sheet's deformation to eliminate the interference caused by the insert's own deformation in the product deformation.
Using a high-temperature, low-pressure injection mode, increase the fixed mould temperature from 70℃ to 95℃ while maintaining the moving mould temperature at 110℃. This will reduce the melt pressure difference and molecular orientation within the mould cavity.
To prevent excessive local pressure at the gate, employ a pressure reduction and holding method that progressively reduces the holding pressure from 80bar to 30bar in steps. This method dynamically reduces the pressure in the internal mould cavity during cooling.
Result of Final Implementation: The yield rate was increased to 99%, and product deformation was reduced to below 0.1mm with only two trial mouldings and a total time of 25 minutes, fully satisfying the mass production requirements.
II. Case Study: Yield Enhancement for Automotive Exterior Parts with 16-Cavity Hot Runners
Initial Fault Status: The multi-cavity mold's appearance qualification rate was consistently maintained at 72%, with some cavities exhibiting dimensional drift, flash, and shrinkage issues. The rework rate was consistently high due to the traditional manual experience-based machine adjustments and repetitive trial mouldings, which resulted in over 8 hours of adjustment time per batch.
Rapid Adjustment and Implementation Steps: The basic parameter framework was locked in before machine operation by pre-optimizing the runner layout, injection pressure, and melt flow direction using 3D simulation to proactively avoid risks of stagnation and air trapping.
To ensure basic consistency between cavities, all cavity dimensional errors were controlled within 0.01mm during the processing stage, thereby reducing the difficulty of parameter adjustments at the source.
The injection moulding machine is endowed with an online monitoring system that captures real-time data on the flow rate, mould temperature, and injection pressure. The system eliminates the necessity for repeated manual parameter modifications by automatically compensating and adjusting when a deviation occurs in a cavity.
Final Implementation Results: The total machine setup time was reduced to 45 minutes, the appearance pass rate was increased to 98%, the overall yield stabilised at or above 95%, revision orders were essentially resolved, and the daily production capacity was increased by 30%.
III. Practical Example of Rapid Mould Change and Machine Setup for 3C Precision Connector Hot Runner Multi-Cavity Moulds
Initial State: The traditional mould change and setup process necessitated 15 trial runs and a 45-minute timeframe to achieve the desired outcome, resulting in a substantial loss of effective production time.
Steps for Implementing Rapid Adjustment: All external preparations are completed off-site using SMED rapid mould change technology. Mould change necessitates solely fundamental procedures, including mould locking and circuitry.
The temperature controller formula library contains the mature process parameters for this mould. The baseline parameters are immediately retrieved with a single click following the mould change, necessitating only a ±5% adjustment to the holding pressure and injection rate parameters for calibration.
Final Implementation Results: The total time required for mould changeover and machine setup was reduced to 18 minutes, production efficiency was increased by 53%, and the product qualification rate reached 99.2%, thereby eradicating the necessity for successive mould trials.
The preparation logic in these instances is seamlessly compatible with your existing hot runner multi-cavity precision injection moulding production line. These solutions can be directly referenced and reused by ordinary maintenance engineers, resulting in a substantial reduction in preparation time and an improvement in mass production yield.
