The cooling behavior of highly crystalline polymers and the shrinkage stresses caused by uneven cooling. It explains how one-sided rapid cooling creates amorphous/crystalline imbalances, leading to warpage, internal stress, and reduced mechanical properties. The article also provides practical methods for detecting overcooling and recommends slowing or interrupting cooling to allow stress relief and annealing.
READ MORE
frequent screen changer clogging and pressure surges in extrusion and injection molding. It emphasizes that the problem is often caused by improper mesh configuration rather than material impurities, and presents a gradient screen pack structure using coarse support, medium transition, and fine filtration layers. Recommended mesh combinations are provided for conventional products, precision extrusion, and high-contamination recycling applications.
READ MORE
This article cautions against pursuing excessively short injection molding cycles (e.g., 2.8 seconds), outlining 20 improper high-speed practices and their consequences. It covers material degradation, gas entrapment, mold and machine component fatigue, hydraulic system damage, and mechanical failures, emphasizing that aggressive cycle reduction compromises part quality and equipment reliability rather than yielding genuine efficiency gains.
READ MORE
the use of three-dimensional response surface methodology (RSM) to optimize twin-screw extrusion parameters—temperature, screw speed, and throughput. By analyzing their interactions, RSM overcomes the limitations of traditional single-factor adjustments. Through a Box–Behnken design, response surfaces are generated to visualize performance sensitivity and identify a multi-objective optimum that balances mechanical properties with production efficiency.
READ MORE