Hot runner system is "core material delivery pipe" in injection mold production. When used smoothly, it can improve efficiency and reduce costs; when problems arise, it's a bottomless pit of money—at best, production stoppages and mold repairs, product scrapping; at worst, the entire system will be destroyed.
This article, starting from actual production, breaks down five most common hot runner problems: material leakage, poor gate appearance, temperature runaway, blockage and degradation, and short lifespan with high maintenance. It explains symptoms and root causes of these faults, how mold design, product design, procurement, and cost control departments can proactively prevent them, fostering cross-departmental collaboration to avoid pitfalls and nip problems in bud.

01 Material Leakage: The Most Costly Sudden Failure, Nine Times Out of Ten It's Due to "Pressure"

Material leakage is overflow of molten plastic from undesigned locations. It's the most destructive problem in hot runner systems. Minor repairs cause production stoppages and downtime, while major repairs can render the entire system unusable.