Poor Demolding / Mold Sticking

The part sticks to the cavity or core and cannot be demolded normally. When demolding is difficult, a "hissing" adhesion tearing sound can be heard at the moment of mold opening, whitening or tearing marks appear on the part surface, and obvious ejector whitening or dents occur at the ejector pin positions. In severe mold sticking, part of the material remains in the cavity and requires shutdown for manual cleaning, which not only prolongs the production cycle but may also damage the cavity surface. For multi-cavity molds, sticking in individual cavities can also cause abnormal filling of the remaining cavities.

1. Process parameter factors: insufficient demolding draft angle, insufficient mold polishing, excessive holding pressure, insufficient cooling. 2. Temperature factors: the settings of barrel temperature and mold temperature directly affect melt fluidity, cooling rate, and crystallization behavior; low temperature is a common cause of filling and molding quality problems, and precise control is required according to the material's recommended processing window.

1. Process parameter optimization and adjustment: increase the demolding draft angle, polish the cavity, reduce holding pressure, extend cooling time, use release agent in appropriate amounts. 2. Systematic troubleshooting method: troubleshoot item by item in the order of "parameters -> material -> mold -> equipment". First adjust the parameters that are easiest to change, such as injection pressure and temperature, and observe the effect; if there is no improvement, check the drying and fluidity of the raw material; further check mold venting and gate design; finally check the mechanical condition of the equipment (check ring, screw). Change only one variable at a time to determine the root cause. 3. Preventive management: establish standardized process parameter cards and quality control limits for each mold/product, and regularly conduct process capability index (CPK) evaluation. For recurring problems, use fishbone diagram or 5Why analysis to trace the root cause, and fix the countermeasures as PFMEA control points.

This problem is a typical manifestation of poor demolding/mold sticking in '2079851475616104452; the core of the solution lies in eliminating the root cause of the defect through systematic optimization of process parameters (temperature, pressure, speed) and rationality checks of mold design. It is recommended to start with process parameter adjustment and gradually go deeper into the equipment and mold levels.