EPGC308 belongs to the class of high-performance epoxy glass cloth laminated sheets, serving as a critical structural insulating material in demanding high-voltage electrical equipment, rail transit, and new energy industries.
Manufactured using electrical-grade alkali-free glass fiber cloth impregnated with high-temperature-resistant epoxy resin, EPGC308 is processed through precision dipping, drying, and curing under high temperature and high pressure. With a continuous temperature resistance rating of Class H (180°C), it provides superior heat resistance and mechanical stability under severe operating conditions compared to standard epoxy laminates.
Specification Overview
- Thermal Rating: Class H (180°C continuous working temperature)
- Standard Sheet Sizes: 1020 × 1220 mm / 1220 × 2440 mm
- Thickness Range: 0.5 mm to 100 mm
- Customization: Full precision CNC machining based on customer drawings
Key Material Performance Advantages of EPGC308
1. Class H Thermal Endurance & Exceptional Mechanical Strength
While conventional epoxy sheets soften, delaminate, or lose mechanical integrity above 130°C, the upgraded epoxy resin formula of EPGC308 ensures exceptional retention of flexural, compressive, and impact strength at temperatures up to 180°C. It easily withstands severe electrodynamic forces generated during high-voltage equipment energization and motor startup without cracking or thermal deformation.
2. High-Voltage Resistance & Moisture-Proof Dielectric Stability
Dielectric reliability is the core capability of EPGC308. It maintains exceptionally high parallel breakdown voltage when immersed in 90°C insulating oil and retains high insulation resistance even after prolonged exposure to water or high-humidity environments. Its low dielectric loss and high tracking resistance effectively prevent creepage and dielectric breakdown in high-voltage switches and dry-type transformers.
3. Chemical & Transformer Oil Corrosion Resistance
Thanks to its dense, high-pressure hot-pressed structure, EPGC308 resists swelling, delamination, or degumming when continuously exposed to transformer oil, organic solvents, and mild acids. This significantly extends the service life of internal structural components and reduces long-term maintenance costs.
4. Precision Machining & High Yield Rate
EPGC308 features a uniform internal density, preventing burring, delamination, or edge chipping during machining. It can be easily milled, drilled, turned, and cut with CNC machinery to produce complex insulating components with high yield rates.
EPGC308 vs. EPGC202 (FR4) vs. EPGC203 (G11)
Selecting the right insulating laminate depends on temperature and electrical performance requirements. Below is a quick comparison between standard grades:
| Grade Standard | Temperature Class | Max Operating Temp | Primary Feature |
|---|---|---|---|
| EPGC308 | Class H | 180°C | Ultra-high thermal stability & high-voltage performance |
| EPGC202 (FR4) | Class B / F | 130°C - 155°C | General-purpose flame-retardant structural insulation |
| EPGC203 (G11) | Class F | 155°C | High mechanical strength at elevated temperatures |
Primary Industrial Applications
Due to its balance of thermal rating, dielectric strength, and mechanical durability, EPGC308 is widely specified across high-end industrial sectors:
- High-Power Motors & Generators: Traction motor slot wedges, end-insulation support plates, and hydro-generator structural spacers.
- Power Transmission & Distribution: Internal load-bearing brackets and insulation barriers in dry-type transformers, high-voltage reactors, switchgear cabinets, and circuit breakers.
- Rail Transit Power Systems: Insulating substrates and frame supports for high-speed railway and subway traction converters and inverters.
- New Energy Equipment: High-temperature insulation components for wind turbines, photovoltaic inverters, and energy storage system (ESS) control cabinets.
- Precision Equipment: Insulating structural load-bearing components for high-frequency and heavy-duty machinery.
Custom Machined EPGC308 Insulation Components
At RDS, we supply off-the-shelf EPGC308 sheets in standard sizes and offer custom CNC machining services to manufacture specialized parts, including insulating blocks, support strips, slot wedges, terminal boards, and threaded rods according to your engineering drawings.
Contact our technical team today to request a quote or discuss specification requirements for your high-temperature insulation projects.