WPC Composite Board Machine Commissioning and Operation Manual

                                                                 WPC Composite Board Machine Commissioning Operating Instructions

I. Pre-Commissioning Preparations

(1) Equipment Inspection

1. Mechanical System: Conduct a comprehensive inspection of all connection points across production line equipment, including bolts and nuts on extruders, haul-offs, cutters, and mixers, ensuring they are securely fastened with no signs of loosening; Verify the installation accuracy of transmission components (gears, chains, belts), ensuring proper meshing, appropriate tension, and absence of jamming or abnormal wear. Confirm adequate lubrication of moving parts such as guide rails and sliders, with grease type conforming to equipment specifications and oil circuits free from leakage.

2. Electrical System: Verify correct wiring within distribution boxes, ensuring secure terminal connections with no loose, short-circuited, or faulty contacts. Inspect wiring polarity of electrical components (motors, sensors, inverters) for accuracy and confirm reliable earth protection. Test responsiveness of control elements (emergency stop buttons, operation switches) to ensure immediate power disconnection upon actuation.

3. Hydraulic / Pneumatic System: Verify oil levels in hydraulic reservoirs and air pressure within specified limits in pneumatic air tanks. Hydraulic oil must be filtered free of contaminants, and compressed air must undergo drying and purification treatment. Inspect hydraulic and pneumatic pipe joints and valves for leaks, ensuring all seals are intact. Test the extension and retraction movements of hydraulic cylinders and pneumatic cylinders for smooth operation, free from stuttering or abnormal vibrations.

(II) Material Preparation

1. Prepare wood-plastic composite raw materials meeting production requirements, including wood flour, plastic pellets (e.g., PVC, PE, etc.) and additives (lubricants, stabilisers, colourants, etc.). Materials must be dried to ≤1% moisture content to prevent defects such as bubbles or cracking in finished products caused by moisture.

2. Accurately measure ingredients according to the formulation ratio. After thorough mixing, store in hoppers to ensure materials are free from lumps and impurities, preventing feed inlet blockages or compromised extrusion quality.

(III) Personnel and Environmental Preparation

1. Commissioning personnel must possess certification for operating wood-plastic production lines, be familiar with equipment structure, operational principles, and safety protocols, and wear appropriate protective gear (safety helmets, protective gloves, safety goggles, etc.).

2. The commissioning site must be kept tidy, free of extraneous clutter, with sufficient operational clearance (≥1.5 metres) around equipment. Ensure stable power supply with voltage fluctuations not exceeding ±5%, provide fire extinguishing equipment, and maintain adequate ventilation.

II. Subsystem Commissioning Procedure

(I) Mixing System Commissioning

1. Start the mixer and run it under no-load conditions for 30 minutes. Observe whether the motor operates smoothly, with no abnormal noise or vibration, and ensure bearing temperatures do not exceed 70°C.

2. Conduct a load test by feeding a small quantity of raw materials according to the formulation. Verify the mixer's blending uniformity; sample testing should show raw material mixing deviation ≤3%. Test whether feed rate and mixing speed adjustment functions operate correctly, and ensure discharge is smooth with no residue or blockages.

3. Inspect the temperature control system (if fitted). After setting the target temperature, observe whether the actual temperature stabilises within ±2℃. Verify heating and cooling functions operate correctly.

(2) Extrusion System Commissioning

1. Preheating: Set barrel and die section temperatures according to material processing requirements. The first section (feed section) should be slightly cooler, with subsequent sections progressively warmer, culminating in the highest temperature at the die. Proceed only after all sections have reached their set temperatures and stabilised for 30 minutes.

2. No-load Test Run: Start the extruder motor at low speed (5-10 rpm). Observe whether the screw rotates smoothly without binding or abnormal noise, and ensure motor current remains within 30% of the rated value. Check that lubrication lines are unobstructed and that there are no leaks at any sealing points.

3. Load adjustment: Gradually increase screw speed (by 5 r/min increments, stabilising for 5 minutes each) while feeding small quantities of material. Observe material plasticisation. Through the die viewing port, check for uniform melt without scorching or bubbles. Should poor plasticisation occur, appropriately raise the corresponding section temperature or reduce speed.

4. Mould commissioning: Adjust mould clearance to ensure uniform extrusion and profile cross-sectional dimensions meeting preliminary requirements. Verify mould heating elements operate normally with stable temperatures and no localised overheating.

(III) Traction System Commissioning

1. No-load operation: Start the traction machine to test synchronisation between upper and lower traction rollers. Adjust the traction speed knob, observing whether speed changes are smooth without jumps or stuttering. Verify pressure regulation function of traction rollers, ensuring even pressure and no deviation.

2. Interlocking Debugging: Interlock with the extruder. Adjust the traction speed according to the extrusion speed, ensuring the traction speed is slightly higher than the extrusion speed (draw ratio 1.05-1.1). This guarantees smooth profile traction without stretching deformation or bending. Monitor the profile surface temperature using an infrared thermometer. If temperatures are excessively high, appropriately increase the traction speed or enhance cooling.

(IV) Cooling System Debugging

1. Activate the cooling water tank/cooling fan. Verify unimpeded water circulation, adequate tank water level, and water temperature maintained between 20-30°C. For air-cooled systems, ensure uniform airflow from the fan with no dead zones.

2. Observe the cooling effect on extruded profiles after passing through the cooling system. Ensure no water marks or deformation appear on the surface, with post-cooling profile temperature ≤40°C. Measure profile straightness deviation using calipers, ensuring deviation ≤0.5mm/m.

(V) Cutting System Commissioning

1. No-load testing: Start the cutting machine. Verify smooth saw blade rotation without vibration or abnormal noise, with normal motor current. Test cutting stroke and positioning accuracy. Manually trigger the cutting command to observe whether the saw blade's vertical movement and feed actions are smooth, and whether the cut surface is flat and burr-free.

2. Interlocking Debugging: Set the cutting length (via encoder or photoelectric sensor) and synchronise with the traction machine to test the automatic cutting function. Perform continuous cutting on 5-10 profiles, measuring the cutting length deviation ≤ ±2mm. Inspect the perpendicularity of the cut profile ends, with deviation ≤ 0.3mm.

III. Integrated Machine Commissioning

(I) Sequential Start-up Procedure

Mixing system → Cooling system → Extrusion system → Traction system → Cutting system. Initiate each system in this order to ensure proper signal interlocking and absence of conflicts.

(b) Parameter Optimisation

1. Conduct continuous production for 30 minutes while comprehensively monitoring all system operating conditions: ensure uniform extruder plasticisation, matching of haul-off speed with extrusion speed, adequate profile cooling, and cutting precision meeting specifications.

2. Sample and inspect critical profile indicators: cross-sectional dimensions (tolerance ≤ ±0.3mm), wall thickness uniformity (tolerance ≤ 0.2mm), curvature, surface finish (free from scratches, bubbles, colour variation). Adjust relevant parameters based on inspection results.

3. Optimise process parameters:

- For surface roughness, increase die head temperature or lubricant ratio.

- For excessive internal stress causing brittleness, reduce cooling rate or adjust formulation.

- For burrs on cut surfaces, increase saw blade speed or adjust cutting clearance.

(3) Stability Testing

1. Operate the entire machine continuously for 2 hours, recording operational data for all systems (motor current, temperature, pressure, speed, etc.) with no abnormal fluctuations. Inspect temperature rise across all equipment components: bearing temperature ≤75°C, motor temperature ≤80°C.

2. Emergency stop function test: During operation, pressing the emergency stop button shall cause the entire machine to halt immediately without inertial coasting. Normal operation shall resume upon restart.

IV. Troubleshooting Common Faults
       Fault Symptom ：Extruder motor tripping due to overload  

       Possible Causes   ：

 1. Screw jam; 

2. Excessive moisture content in raw material;

3. Barrel temperature too low, resulting in poor plasticisation;

4. Electrical circuit fault  

        Resolution ：

 1. Shut down and clear the screw, inspect for foreign objects;

2. Dry the raw material to ensure moisture content meets specifications;           

3. Increase barrel temperature and extend preheating time;

4. Inspect circuitry and frequency converter to eliminate short circuits or overload protection faults

    Fault Symptom ：  Bubbles on profile surface  

 Possible Causes   ： 

1. High moisture content in raw material;

2. Excessive barrel temperature causing material decomposition;

3. Inadequate mould venting  

 Resolution ：

  1. Re-dry raw material;

2. Reduce temperature in corresponding barrel section;

3. Clear mould vent holes and increase vent channels
Traction machine deviation    1. Uneven traction roller pressure; 2. Profile extrusion eccentricity; 3. Contaminants on traction roller surface    1. Adjust traction roller pressure to ensure symmetrical pressure on both sides; 2. Align mould centre to correct extrusion eccentricity; 3. Clean traction roller surface to maintain cleanliness
Significant cutting length deviation    1. Encoder malfunction; 2. Unstable traction speed; 3. Loose cutting positioning mechanism    1. Inspect encoder wiring, calibrate or replace; 2. Service traction machine speed control system to ensure smooth operation; 3. Tighten cutting positioning mechanism bolts and recalibrate
Uneven material mixing    1. Insufficient mixing speed; 2. Incorrect ingredient ratios; 3. Inadequate mixing duration    1. Increase mixing speed; 2. Recheck formula and ensure precise ingredient measurement; 3. Extend mixing time to guarantee thorough blending