Daily Maintenance
Perform daily maintenance at the start of each shift or after every 8 hours of operation. These checks take approximately 10–15 minutes.
Pre-Start Inspection (Beginning of Shift)
| Item | Check Point | Criteria |
|---|---|---|
| Hydraulic oil level | Sight glass on tank | Between 2/3 and 3/4 of sight glass |
| Hydraulic oil temperature | Controller HMI or oil thermometer | 20–55°C (ideal), < 60°C (alarm) |
| Coolant flow | Flow indicator / return sight glass | Steady flow, no air bubbles |
| Lubrication system | Grease reservoir level | ≥ 1/3 full |
| Lubrication lines | Visual check at lubrication points | Oil present at all points |
| Tie bar nuts | Visual check | No visible loosening or shifting |
| Safety doors | Open/close both front and rear doors | Smooth operation, switches click |
| Emergency stop | Press and release each E-stop button | Immediate stop, proper reset |
| Hydraulic leaks | Floor under machine, hose connections | No active drips or puddles |
| Oil filter indicator | Vacuum/pressure gauge on filter | Within green zone |
| Barrel heater bands | Visual check | No discoloration, no loose wires |
| Thermocouples | HMI temperature readout | Stable readings, no open-circuit alarms |
| Screw / barrel area | Visual check | No material leakage from nozzle or vent |
During Operation Checks
| Item | Observation | Action if Abnormal |
|---|---|---|
| Abnormal noise from pump | Steady hum, no knocking/grinding | Stop machine, inspect pump coupling and mounting |
| Abnormal vibration | Smooth cycle motion | Check tie bar tension, leveling, anchor bolts |
| Oil temperature trend | Rising toward 55°C+ | Check cooler, clean if needed |
| Cycle time drift | Compared to baseline | Check hydraulic valves, accumulators, material |
| Product quality variation | Weight, dimensions, flash | Check mold, process parameters |
End of Shift
- Clean the machine area — remove oil, plastic drool, and debris
- Record oil temperature at end of shift
- Log any alarms or unusual observations in the machine logbook
- If the machine will idle > 8 hours, purge the barrel with a heat-stable material (e.g., PP or HDPE)
⚠️
Never leave the machine with heat-sensitive material (e.g., PVC, POM) in the barrel during an extended shutdown. Purge immediately.