# Injection Mold Maintenance Checklist > Source: https://netray.co/tools/injection-mold-maintenance-checklist > Publisher: Netray (netray.co), AI and integration engineering for ERP and manufacturing systems. > Section: Free Tools ## Short answer A practical preventive maintenance checklist for injection molds, from daily checks at the press to full overhaul and storage. ## Category maintenance ## Industry Plastics and Injection Molding ## Audience - Mold maintenance technician - Toolroom supervisor - Molder - Plant manager ## Tool **Kind:** checklist **Scoring Note:** Mark each item as done. A mold with any critical item open should not return to production until it is cleared. **Groups:** #### At the press (every setup and each shift) **Items:** **Text:** Confirm mold ID and cavity count match the job and the set-up sheet **Critical:** true **Text:** Check that clamps, straps or hooks are secure and bolts are the correct length **Critical:** true **Text:** Verify water lines are connected to the correct circuits and there are no leaks **Critical:** true Check for flash, short shots or burn marks on the first off-tool parts Confirm hot runner temperatures reach setpoint and zones are balanced **Text:** Inspect parting line and ejector pins for damage before closing at low pressure **Critical:** true **Text:** Verify low-pressure mold protection is on and the setting is correct **Critical:** true Record shot count and any abnormal event on the mold log Check that the mold is clean and free of oil, grease and rust preventative before run #### Preventive maintenance at a set shot interval **Items:** Clean vents and check vent depth, including vent slots at end of fill Clean and lubricate guide pins, bushings and slides with approved grease Check and lubricate ejector pins, sleeves and return pins; replace bent or galled ones **Text:** Inspect cores, cavities and parting line for wear, galling and peening **Critical:** true Check shut-off surfaces for wear that could cause flash **Text:** Test cooling channels for flow and blockage; note pressure drop versus baseline **Critical:** true Inspect water fittings, O-rings and seals; replace any that are weeping **Text:** Check heater bands, thermocouples and wiring on hot runner manifold and nozzles **Critical:** true Verify slide, lifter and angle pin wear plate condition and clearance Check limit switches, sensors and hydraulic or pneumatic lines on core pulls Inspect gate area for wear, erosion or damage and confirm gate vestige is in spec Check locating ring, sprue bushing seat and nozzle radius match Check texture and polish for wear or damage and record any refurbishment need #### Overhaul (annual or at a major shot count) **Items:** **Text:** Fully disassemble, clean and degrease all plates and components **Critical:** true Measure critical cavity and core dimensions against the drawing or baseline Check plate flatness, parallelism and parting line fit with bluing **Text:** Replace worn components: ejector pins, bushings, springs, seals, heaters **Critical:** true Descale and pressure test cooling circuits; consider flushing with approved descaler Test hot runner heaters for resistance and insulation, and replace nozzle tips as needed Re-polish or re-texture as required and approve against the sample Reassemble, torque bolts to specification and test all moving components **Text:** Run a sample shot and confirm parts meet the dimensional report **Critical:** true Update the mold history record with work done, parts replaced and sign-off #### Storage and removal from service **Items:** **Text:** Purge the cavity of resin and blow out water lines before pulling the mold **Critical:** true Spray cavity and core surfaces with rust preventative and close the mold Fit protective covers and close-up clamps or bolts on the parting line Cap water fittings and hot runner connections **Text:** Tag the mold with its status, last shot count and any known issues **Critical:** true Store off the floor on a rack rated for the mold weight in a dry area Record location in the tooling system or ERP asset record ## Content **Intro:** A mold that is maintained on a plan runs longer, makes better parts and creates fewer line stoppages. This checklist groups the work into four levels so a toolroom can adopt it as a base and tailor the intervals to each tool. **Sections:** #### How to use the checklist **Body:** Print it or complete it on screen and export to PDF or Excel. The first group belongs to the setter at the press, the second to the toolroom at a shot-count interval, the third to a full overhaul and the fourth to storage. Critical items are those that, if missed, risk tool damage, safety incidents or scrap. Add tool-specific items, such as a particular slide or lifter inspection, and save a copy per mold so the history is on record. #### Setting the intervals **Body:** There is no single correct number of shots between PM events. A simple commodity mold in soft resin may go many hundred thousand shots, while a glass-filled or abrasive resin mold needs attention far more often. Many shops start with a shot count tied to the tool class and shorten it based on what the inspection finds: wear on vents, pins and shut-offs, flash trends and cooling performance. Review every finding and reset the interval, rather than treating the first guess as permanent. #### What to record **Body:** A PM that is not recorded cannot be improved. Keep the shot count, date, work done, parts replaced, measurements and the person who signed it off. Cooling pressure drop, vent depth and pin wear trends predict failures before they happen. In many ERPs and CMMS tools, a mold can be an asset with a counter, so a PM work order can trigger from shot count rather than the calendar. The same record supports customer audits on tool control. #### Common mistakes **Body:** Cleaning molds with metal tools or abrasive pads damages polish and shut-offs. Using the wrong grease can contaminate parts, especially for medical or food contact. Storing a mold without rust preventative, or with water left in the circuits, causes corrosion that shows up at the next startup. Skipping vent cleaning is the leading cause of burn marks and short shots after a long run. Finally, failing to update shot counts makes any interval based PM guesswork. **Cta:** If you want mold shot counts to trigger maintenance work orders in your ERP or CMMS, we can help set that up. Ask for a short review. **Faq:** #### How often should an injection mold be serviced? **Answer:** It depends on the resin, tool complexity and run volume. Many shops use shot-count triggers set by tool class and then adjust from inspection findings. Abrasive or glass-filled resins and complex tools need shorter intervals. #### What is the most common cause of mold wear? **Answer:** Abrasive fillers such as glass fiber, flash that hammers shut-off surfaces, poor cleaning practice and lack of lubrication on slides and pins are leading causes of wear. #### How should I clean a mold safely? **Answer:** Use brass or plastic tools and approved mold cleaners, never steel scrapers or abrasive pads on polished surfaces. Dry thoroughly and apply the right rust preventative before storage. #### Should mold maintenance be tracked in the ERP? **Answer:** If your ERP or CMMS supports asset counters, yes. Track shot counts, PM history and location so maintenance triggers on usage rather than the calendar. ## Search terms injection mold maintenance checklist, mold preventive maintenance checklist, mold maintenance schedule, plastic injection mold PM, mold cleaning checklist, mold storage procedure, mold maintenance log --- Talk to an engineer: https://netray.co/contact?intent=erp_ai | Machine catalog: https://netray.co/agent/catalog.json