Mold Maintenance and Repair Guide - Extending Tool Life
Injection mold maintenance guide: preventive maintenance schedules, common repair issues, surface restoration, and storage best practices.
Why Mold Maintenance Matters
Regular maintenance prevents downtime, maintains quality, extends tool life. A well-maintained mold produces 500k to 5M cycles depending on steel and application.
Preventive Maintenance Schedule
After Each Run
Clean cavity and core surfaces
Check and clean vents
Apply rust preventive
Lubricate pins and bushings
Document part count
Weekly (50k-100k cycles)
Visual inspection for wear, pitting, corrosion
Check ejector pin heights (0.02-0.05 mm clearance)
Verify cooling channel flow and temperature
Inspect hot runner system
Monthly (200k-500k cycles)
Disassemble and clean all plates
Inspect parting line surfaces
Replace worn pins and springs
Check heater bands and thermocouples
Common Repairs
Parting line damage: micro-welding + re-machining ($200-800)
Ejector pin wear: replace pins ($50-300 per pin)
Gate wear: re-cut or replace inserts ($100-500)
Cooling leaks: weld and re-drill ($200-1000)
Hot runner leaks: replace seals/nozzles ($500-3000)
Surface Restoration
Polishing: Diamond paste (0.5-6 micron)
Chrome Plating: 0.05 mm layer restores dimensions
PVD Coating: TiN, TiAlN, DLC for wear resistance
Storage
Store molds vertically
Climate-controlled: 20-25C, under 50% humidity
Apply heavy rust preventive
Wrap in VCI paper
Tag with part number, cycle count, last service date