1. Visual & Document Check
First verify machine model, manufacturing year, serial number and maintenance records. Check overall frame for heavy rust, cracks, oil leakage and missing parts. Confirm the whole line matches the configuration listed: twin screw extruder, mould, vacuum calibration table, haul-off, cutter and stacking unit.
2. Core Extruder Parts
- Screw & Barrel: Check surface erosion, scratches and flight wear. Heavy wear will reduce plasticizing performance and output. Measure gap if possible.
- Gearbox & Motor: Run the machine without material. Listen for abnormal noise, vibration and oil leaks. Check motor temperature and current stability.
- Heating & Temperature Control: Test all heating zones and thermocouples. Stable temperature control is critical for PVC profile quality.
3. Vacuum, Cooling and Haul-off System
- Vacuum tank: Check vacuum pump performance, seal leakage and vacuum stability. Poor vacuum causes profile bubbles and dimension errors.
- Cooling water circuit: Check pipe blockage, water leakage and uniform cooling.
- Haul-off: Test belt clamping and pulling synchronisation. Slipping will result in unstable profile size.
4. Cutter & Electrical Control Cabinet
Check cutting unit for smooth cutting, no burrs and accurate length. Open electrical cabinet, inspect PLC, frequency converter and wiring aging. Test emergency stop and safety alarms.
5. On-Site Trial Run Suggestion
A live test run with PVC raw material is highly recommended. Observe profile surface, dimensional tolerance, extrusion stability and current fluctuation during production. Record defects and negotiate repair or part replacement before shipment.
Final Tip
A full inspection reduces investment risk. We supply well-tested used PVC profile production lines with complete pre-shipment inspection, spare parts support and after-sale technical service. Contact us for available second-hand PVC profile extrusion lines.
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