Based on the previously established three-level wear assessment criteria for hot runner sheaths (appearance, performance, and service life), the following repair solutions are precisely tailored to different wear levels:
Minor Wear: Only surface polishing and grinding are performed to clean shallow scratches and dirt. High thermal conductivity silicone grease is applied, and temperature measurement accuracy is calibrated. No additional coating treatment is required, resulting in extremely low cost.
Moderate Wear: The old, detached coating is thoroughly removed. A new nano-ceramic coating is prepared using a thermal spraying process to restore insulation and wear resistance, allowing for continued operation under normal conditions.
Severe Wear: The deformed areas are reshaped and then coated with a PVD tungsten carbide coating. Sheaths that cannot be reshaped are directly replaced, completely avoiding the risks of adhesive leakage and electrical leakage.
Graded repair maximizes the restoration of sheath performance and extends the overall lifespan of the hot runner while controlling costs.
