Based on the previously established three-level wear grading standard for hot runner sheaths, precise repair is required according to the wear level:
Level 1 (Minor Wear): Polish shallow scratches with 1200-grit sandpaper, clean, apply high thermal conductivity silicone grease, and calibrate temperature measurement accuracy. No additional coating treatment is needed.
Level 2 (Moderate Wear): Thoroughly remove the flaked old coating, apply a nano-ceramic coating using thermal spraying to restore insulation and wear resistance.
Level 3 (Severe Wear): Reshape the deformed area and deposit a PVD tungsten carbide coating. Sheaths that cannot be repaired should be replaced directly to avoid the risk of glue leakage and electrical leakage.
Graded repair maximizes the restoration of sheath performance and extends the overall lifespan of the hot runner system while controlling costs.
