Safety Precautions
To protect personnel, maintain performance, and prolong machine life, observe the following rules during operation and maintenance:
• Operators must be trained and fully familiar with the machine’s structure, performance, and operating procedures before starting or handling the equipment.
• Do not start the machine if safety devices are missing, damaged, or ineffective.
• Avoid contact with moving or heated parts while the machine is running.
• Only one person should operate the machine at a time, except when installing secure molds under supervision.
• Never run the screw at high speed (>30 RPM) without material in the groove—this can cause scoring of the barrel and screw.
• Heat the cylinder from room temperature to set point within approximately 3 minutes. Allow cold residue to soak for at least 10 minutes before beginning plasticizing to prevent damage.
• Start cooling water circulation early; adjust flow rate gradually once oil temperature rises by 5–10°C. Maintain oil temperature below 55°C.
• Lubrication must strictly comply with operational requirements. Insufficient lubrication may lead to wear, seizure, or failure—especially in clamping mechanisms like tie bars and bushings.
• Regularly inspect electric heating coils for looseness due to thermal expansion. Tighten promptly upon detection.
• Always ground the machine properly and periodically check electrical insulation to prevent shock hazards.
• After long-term storage or initial use, allow the oil pump to idle for several minutes before full operation.
⚠️ Warning: Improper operation, neglected maintenance, or misuse can result in serious injury, equipment damage, or reduced lifespan.
Routine Inspection Checklist
Daily Checks
✔️ Wear appropriate work attire
✔️ Check for loose or disconnected heating rings
✔️ Ensure nozzle temperature control functions correctly ("0" setting verified)
✔️ Test all switches—especially safety doors and emergency stop buttons
✔️ Inspect mold fixing screws for tightness
✔️ Verify circulating coolant supply and flow
✔️ Monitor hydraulic oil level in reservoir
✔️ Examine lubricating lines and joints for leaks
Weekly Checks
✔️ Confirm proper lubrication across all moving parts
✔️ Inspect position sensor screws for loosening
✔️ Validate thermocouple connections and responsiveness
✔️ Measure ground wire resistance
✔️ Check pressure tubing and fittings for signs of leakage or wear
Periodic Maintenance (Based on Usage)
Interval |
Task |
Every 3 months |
Assess hydraulic oil condition; replace if contaminated. Clean filters: suction, breather, return. Replace as needed. |
Every 2,000 machine hours |
Lubricate mold thread rods. Inspect high-pressure hoses. Replace if worn. |
Every 5,000 machine hours |
Replace hydraulic oil and tank breather filter. |
Every 25,000 machine hours / Max 5 years |
Replace hydraulic cylinder seals, friction rings, and high-pressure hoses as required. |
Lubrication System
Use only specified thin oil and hydraulic fluid to avoid compromising lubrication effectiveness.
• All lubrication points are indicated in the attached diagram.
• Centralized, computer-controlled quantitative lubrication system ensures consistent delivery.
• Typical refueling frequency: every 30–50 mold cycles, lasting ~10 seconds per cycle.
🔧 New Machine Note: Before commissioning, manually prime each lubrication line and point to eliminate air pockets.
Barrel and Screw Cleaning Procedures
Contaminated materials or color changes require timely cleaning to maintain product quality and prevent degradation.
When to Clean?
• Changeover to new material: recommended purge.
• Color change after 20–30 shots: partial or complete clean depending on contamination level.
• Surface defects (uneven thickness, streaks): likely caused by residual buildup in feed zone, check valve, or screw tip.
Types of Cleaning
Partial Cleaning
Focus on:
• Nozzle orifice
• Sealing surface of the cylinder head
• Front of the screw near the nozzle
• Tip of the screw
✅ Use protective gloves, goggles, and mask. Work cautiously.
Complete Cleaning
Required when:
Products show uneven texture or subtle blemishes
Residue accumulates in critical areas (feed throat, screw root, non-return valve)
High-performance resins used (e.g., polycarbonate, nylon)
Caution: Heating releases toxic fumes. Ventilate thoroughly. Isolate cleaning area from active operations.
Step-by-Step Complete Cleaning Process
1) Preparation:
Keep barrel warm—never completely cool.
Purge leftover material through the nozzle at medium injection speed.
2) Heating:
Reheat barrel using all heaters.
After ~15 minutes, remove nozzle and plug.
Continue heating until residual material softens enough to rotate the screw gently.
3) Disassembly:
Remove heater bands.
Unscrew the cylinder head.
Extract the screw, keeping it supported between templates.
4) Cleaning:
Scrape excess residue with cloth-wrapped wooden stick.
Use brass brush wrapped in fine gauze (grade 240–280) to polish interior surfaces.
Avoid grinding sealing faces.
Brush threads clean.
5) Post-Cleaning Protection:
Apply anti-rust oil to all exposed metal surfaces.
Coat threads with HSC ointment before reinstallation.
⚠️ Critical: Allow all components to reach thermal equilibrium before assembly. Mismatched temperatures risk warping or cracking.
Screw Cleaning
Gently heat the screw uniformly—do not concentrate flame on one spot.
Max temperature: 400°C — beyond this risks loss of hardness and wear resistance.
Burn off residues with propane torch; immediately brush clean.
Polish screw surface with emery cloth.
Apply HSC-ointment only—no other grease or lubricant. Others carbonize and jam the coupling.
❗ Never force-fit mismatched components. Align thrust collar precisely during installation.
Screw Head (Front End) Maintenance
Remove using spanner wrench—note: left-hand thread.
Clean internal threads and shut-off ring carefully.
Polish pressure ring and thrust collar.
Reassemble with correct orientation.
PPE Required: Gloves, face shield, respirator—especially when removing hot components.
Nozzle Maintenance
1. Remove plastic buildup by burning.
2. Brush clean with steel wire.
3. Polish gently with fine emery cloth.
❌ Never grind around the sealing surface.
Reinstall only after confirming alignment and temperature balance.
Hydraulic Oil Replacement
Follow manufacturer guidelines based on usage intensity.
Procedure:
1. Drain old oil via pump or siphon through port A.
2. Thoroughly clean tank—remove sludge/residue.
3. Open cover and inspect base.
4. Refill with approved hydraulic fluid meeting GB7631.2-87 standard.
5. Never mix different brands or grades.
♻️ Pollution Control: Dispose of used oil responsibly—return to supplier or authorized facility.
Air Filter Maintenance
• Open housing.
• Replace filter core.
• Close securely.
❗ Improper sealing causes leaks. Do not start motor until confirmed installed.
Oil Filter Cleaning
Located inside hydraulic tank.
Tools Needed:
• Soft brush
• Approved solvent
• Clean rags
Steps:
1)Power off machine.
2)Drain hydraulic oil.
3)Open tank.
4)Remove and clean filter.
5)Reinstall.
Hose Clamp & Hose Inspection
Check regularly according to maintenance schedule.
Replace hoses immediately if any of these conditions occur:
• Skin damage affecting braid integrity.
• Brittle or cracked outer layer.
• Deformation under pressure/bending.
• Bulging, blistering, or splitting.
• Seal deformation impairing function.
• Collar corrosion or separation.
• Exceeded shelf life or working hours.
Protective Door Viewport Cleaning
• Wipe with soft cloth dampened in mild detergent solution.
• Rinse with clean water.
❌ Never use abrasive cleaners, solvents, or rough fabrics.