With electric vehicles (EVs) rapidly becoming the norm, demand for high-quality EV charging cables has skyrocketed. Yet one persistent challenge in production is overheating during EV cable extrusion. Left unmanaged, this can lead to insulation deformation, material degradation, and costly production downtime. Understanding the causes, prevention methods, and real-world strategies is key for manufacturers striving to deliver safe and reliable cables.

Why Overheating Happens in EV Cable Extrusion

Overheating occurs when the insulation material exceeds its optimal processing temperature. Common factors include:

• Localized friction in extruder screws

• Incorrect barrel or die temperature settings

• Inconsistent material flow or viscosity

Consequences include: deformed insulation, reduced mechanical strength, poor electrical performance, and increased scrap rates. For multi-core EV cables, even minor overheating can affect dimensional uniformity and long-term reliability.

Industry Example: A mid-sized EV cable manufacturer noticed repeated insulation bubble defects. Analysis revealed uneven feeding in the extrusion screw, which created hotspots. After installing a precision dosing system and real-time temperature sensors, defect rates dropped by 65%.

Step 1: Invest in High-Performance Extrusion Machinery

Advanced extrusion equipment is the first step to controlling thermal issues. Key features to consider:

• PLC-controlled temperature zones for barrel, die, and screw

• Optimized screw designs to minimize friction and heat buildup

• Automated feedback loops to adjust process parameters in real time

Tip: Look for machines with integrated thermal monitoring dashboards; they provide early warning for temperature deviations and prevent costly mistakes.

Step 2: Optimize Cooling Systems

Effective cooling stabilizes the cable immediately after extrusion. Recommended strategies:

• Water baths for rapid surface heat removal

• Air tunnels for uniform cooling along cable length

• Post-extrusion chillers to maintain dimensional accuracy

Best Practice: Monitor both cable surface and core temperatures. Uneven cooling can cause insulation shrinkage, leading to short circuits or assembly problems downstream.

Step 3: Maintain Material Flow and Viscosity

Smooth, consistent material flow is essential to prevent internal heat buildup. Methods include:

• Using high-quality PVC or XLPE compounds with consistent viscosity

• Maintaining uniform feeding through precision dosing systems

• Adjusting screw speed and torque to balance shear heat

Even minor fluctuations in flow or viscosity can create hotspots, so continuous monitoring is essential.

Step 4: Conduct Preventive Maintenance

Preventive maintenance reduces overheating risk and extends equipment life. Recommended actions:

• Regular cleaning of screws and barrel liners

• Thermocouple calibration for accurate temperature readings

• Inspection of mechanical alignment and lubrication to avoid friction hotspots

Manufacturers who schedule routine maintenance see fewer defects, longer equipment lifespan, and higher production efficiency.

Step 5: Industry Best Practices and Tips

• Document extrusion parameters: Maintain records of barrel, die, and cooling settings for different cable types.

• Implement alarms and alerts: Automated systems can flag temperature spikes or abnormal material flow.

• Train operators: Skilled technicians can identify early signs of overheating, reducing defects and waste.

Conclusion: Produce High-Quality EV Cables Safely

Preventing overheating in EV charging cable extrusion is essential for product reliability, safety, and efficiency. By combining high-performance extrusion machinery, optimized cooling, careful material monitoring, and rigorous preventive maintenance, manufacturers can achieve high-quality cables that meet the growing demands of the EV market.

At DX Cable Tech, we provide industry-leading extrusion solutions for EV cable manufacturing, helping engineers and factory managers maintain thermal stability, reduce defects, and maximize productivity.