How Feilong Polyurethane Equipment Solves Bubble and Uneven Curing Issues in Epoxy Resin Potting Compound Production

Epoxy resin potting compounds play a critical role in protecting electronic components. However, persistent challenges such as bubbles and uneven curing during production have long troubled the industry. According to industry research, bubble defects reduce product yield by 15–30%, while uneven curing causes insulation performance fluctuations of over 10%, directly affecting product reliability.

1. Key Causes and Impact of Bubbles

• Raw Material Mixing Issues: When stirring speeds exceed 2,000 RPM, high-viscosity compounds (>8,000 cP) easily trap air. Lightweight fillers (e.g., silica) further entrap bubbles, forming micro-voids inside the compound.
• Defective Degassing Process: Traditional equipment with insufficient vacuum (<–0.095 MPa) or short degassing times (<3 minutes) fails to eliminate bubbles. Studies show that un-degassed compounds can lose 50% insulation strength under high pressure and develop moisture channels in humid conditions.
• Environmental Interference: Ambient temperatures below 15°C or above 35°C cause significant resin viscosity fluctuations. Humidity >60% introduces moisture, further aggravating bubble formation.

2. Root Causes of Uneven Curing

• Unstable Temperature Control: Non-uniform oven temperature (±5°C) or lack of stepwise heating causes thick layers (>5 mm) to experience temperature differences up to 80°C, leading to incomplete local curing.
• Insufficient Mixing & Ratio Accuracy: Inadequate static mixer elements or mixing time (<15 minutes) results in poor resin-hardener blending. A ratio error >3% directly causes cure degree variations.
• Poor Mold Design: Insufficient venting or improper flow channels create turbulence and flow restrictions, resulting in internal stress concentration and cracking.

3. Feilong Polyurethane Equipment Solutions

Feilong addresses these pain points with a “Precision Control + Intelligent Process” strategy, integrating four core modules:

3.1 High-Precision Dynamic Mixing System

• PLC-controlled dual-component metering pumps (error ≤0.5%) with synchronized gear pumps ensure ratio accuracy of ±2%.
• Multi-stage filtration (5 μm) removes impurities.
• Planetary dynamic mixer (rotation + revolution) achieves >99.5% mixing uniformity, solving static mixer issues.
• Supports viscosities from 1,000–10,000 mPa·s, covering diverse formulations.

3.2 High-Efficiency Vacuum Degassing

• Creates a –0.095 to –0.1 MPa vacuum (chamber size: 104×104×70 cm).
• Combines planetary stirring with stepwise degassing (5-min standing → 3-min vacuum → 2-min post-potting vacuum).
• Residual bubble rate <0.1%; vacuum pump speed 30 L/s, reaching target in 35 seconds, reducing cycle time by 25%.

3.3 Intelligent Temperature Control Module

• Zone heating with ±1°C precision and IR sensors for real-time monitoring.
• Stepwise curing algorithm (40°C × 2 hrs → 60°C × 1 hr) reduces thermal stress and ensures uniform curing.
• Improves cure uniformity by 40% while cutting energy consumption by 15%—ideal for large components like motors and transformers.

3.4 Fully Automated Production Line

• Integrates feeding, preheating, potting, curing, and inspection.
• Double-speed chain conveyor (±0.03 mm positioning) with MES system minimizes manual intervention by 70%.
• Automatic defect detection lowers defect rates to <0.3%, tripling per capita productivity.

4. Industry Value & Future Trends

Feilong’s solutions deliver significant benefits:

• Efficiency: Changeover time reduced to 30 mins, OEE reaches 85%.
• Quality: Yield improved by 20–40%, insulation performance up by 30%.
• Cost: Raw material waste down by 20–30%, annual maintenance cost cut by 30%.

Future Development Directions

• Intelligent Manufacturing: AI vision for bubble detection, adaptive parameter control, and digital twin production lines.
• Green Technology: Solvent-free processes and energy-saving vacuum systems (energy reduction 25%).
• Integration: Combining specialized equipment with nanofillers and real-time viscosity monitoring for precise material-process matching.

With applications in EVs, power equipment, and advanced electronics, Feilong Polyurethane Equipment is driving epoxy potting compound production toward high quality and low energy consumption.