Maintenance of Injection Molding Machines: The "SPA" for Your Machine

1. Daily "Basic Care" Before Work Ends

• Wipe It Down: Use a dry cloth to clean off the machine’s surface oil and plastic residue (don’t use water; you don’t want to risk an electrical short).
• Check Oil Level: Glance at the hydraulic oil tank level (if it’s below the mark, top it up, just like you would with a car).
• Feel the Heat: Touch the hydraulic oil lines with the back of your hand—if it’s too hot, check the cooling system (normal temperature shouldn’t exceed 60°C).
• Listen for Odd Noises: When starting the machine, listen for any "creaking" noises (if you hear anything unusual, stop the machine and check immediately).

2. Weekly "Deep Clean"

• Tighten Screws: Use a wrench to go over all the screws on the machine (vibrations can loosen them, so don’t wait until they fall out).
• Clean Filters: Remove the hydraulic oil filter, soak it in diesel, and scrub off any metal shavings or impurities (a clogged filter can damage the oil pump).
• Check for Oil Leaks: Get down on the floor and look for any oil stains under the machine (if you see leaks, replace the seals right away).
• Lubricate Moving Parts: Apply grease to the guides and bearings (like oiling a bike chain to prevent dry grinding).

3. Monthly "Health Check"

• Replace Filters: Change the hydraulic oil filter every month (a dirty filter is like running with a mask on; the machine can’t "breathe" properly).
• Check Heating Elements: Use a temperature gun to check the heating bands on the barrel; replace any that aren’t heating evenly (this prevents the plastic from being undercooked).
• Clean the Barrel: After stopping the machine, shoot out any remaining material and flush the barrel with cleaning material (PP or PE) to avoid carbonized residue clogging the nozzle.
• Calibrate Parameters: Check the accuracy of pressure gauges and temperature controllers (if they’re inaccurate, it’s like an oven with erratic temperatures, and you won’t get good products).

4. Annual "Major Service"

• Change Hydraulic Oil: Drain the old oil, clean the tank, and refill with new oil (like changing the oil in a car; don’t skip this step).
• Inspect Electricals: Have an electrician check the motor and wiring for insulation (old machines can have frayed wires that could cause electric shocks).
• Disassemble the Screw: Have the manufacturer take out the screw and barrel, and polish them to remove rust (rust can contaminate the plastic).
• Replace Seals: Replace all hydraulic cylinder seals and O-rings (old rubber can leak, turning your machine into an "oil guzzler").

5. Common Problem "First Aid Kit"

• Hydraulic Oil Turns Black: Change the oil and filter immediately, and check if the oil pump is worn.
• Weak Injection: Check for clogged oil lines and screw wear (a worn screw is like a toothbrush with bristles worn down).
• Mold Won’t Close: Clean any debris from the guides and adjust the alignment (a misaligned mold is like a crooked-mouthed teapot that can’t pour properly).
• Plastic Leakage: Check if the heating bands or thermocouples are faulty, and if the barrel temperature is sufficient (if the plastic isn’t fully melted, it will flow erratically).

Easy-to-Remember Tips