Description
Our G7 silicone glass laminate (also designated as 3250/G7, SI GC 201/202, or F894/G7) represents the pinnacle of thermoset composite technology. The material is produced by layering multiple sheets of electrical-grade woven glass fabric, each meticulously saturated with high-purity silicone resin binder. Through precise thermal processing under controlled pressure, a chemical polymerization reaction occurs, transforming the individual layers into a unified, dimensionally stable thermoset structure that cannot be re-softened.
This sophisticated manufacturing process yields a material with:
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Exceptional thermal endurance for continuous operation exceeding 180°C
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Superior dielectric properties maintaining insulation integrity in both dry and humid conditions
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Outstanding arc resistance exceeding 240 seconds for high-voltage applications
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Self-extinguishing characteristics meeting UL94 V-0 flammability standards
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Robust mechanical strength suitable for structural insulation components
Quality Assurance & Compliance
SIDA’s G7 laminate conforms to multiple international standards:
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NEMA LI-1 G7 (National Electrical Manufacturers Association)
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IEC 60893-3-6 (International Electrotechnical Commission)
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DIN 7735 Hgw 2572 (German Industrial Standard)
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CEI EN 60893 (European Standard)
Each batch undergoes rigorous testing for electrical, mechanical, and thermal properties to ensure consistent performance in critical applications.
Technical Specifications
Physical Properties
| Property | Unit | Typical Value | Test Method |
|---|---|---|---|
| Color | – | White / Cream | Visual |
| Density | g/cm³ | 1.80 ± 0.05 | ASTM D792 |
| Water Absorption | % | ≤0.10 | ASTM D570 (24h) |
| Thermal Class | – | H (180°C) | IEC 60085 |
| Flammability | – | UL94 V-0 | IEC 60707 |
Mechanical Properties
| Property | Unit | Lengthwise | Crosswise | Test Method |
|---|---|---|---|---|
| Tensile Strength | MPa | 138-150 | 138-150 | ASTM D638 |
| Flexural Strength | MPa | ≥120 | ≥65 | ASTM D790 |
| Flexural Modulus | GPa | 11.0 | – | ASTM D790 |
| Compressive Strength | MPa | ≥345 | – | ASTM D695 |
| Impact Strength (Charpy) | kJ/m² | ≥35 | – | ISO 179 |
| IZOD Impact (Notched) | kJ/m² | ≥21 | – | ASTM D256 |
| Hardness (Rockwell M) | – | 105 | – | ASTM D785 |
Electrical Properties
| Property | Unit | Value | Test Method |
|---|---|---|---|
| Dielectric Strength (1/8″) | kV/mm | ≥13.8 (350 V/mil) | ASTM D149 |
| Breakdown Voltage (Parallel) | kV | ≥30 (in 90°C oil) | IEC 60893 |
| Volume Resistivity | Ω·cm | ≥10¹⁴ | ASTM D257 |
| Surface Resistivity | Ω | ≥10¹³ | ASTM D257 |
| Dielectric Constant (1 MHz) | – | 4.5-6.0 | ASTM D150 |
| Dissipation Factor (1 MHz) | – | ≤0.018-0.07 | ASTM D150 |
| Arc Resistance | seconds | ≥180-240 | ASTM D495 |
| Tracking Resistance | – | High | IEC 60112 |
Thermal Properties
| Property | Unit | Value | Test Method |
|---|---|---|---|
| Continuous Operating Temp | °C | 180 | IEC 60085 |
| Short-term Peak Temp | °C | 250 | – |
| Thermal Conductivity | W/(m·K) | 0.3-0.4 | ASTM C177 |
| Coefficient of Thermal Expansion | 10⁻⁶/°C | 12-18 | ASTM D696 |
Note:The product specifications provided are for reference purposes only. Please refer to the actual product for final specifications. We also offer various sizes and thicknesses to meet your specific needs. For further customization, please contact us.
Application Scenarios
1. Electrical Equipment Insulation
Core Applications:
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Motor Slot Wedges: Ideal for Class H motors requiring high-temperature slot insulation and winding support
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Transformer Components: Insulating slots, windings, gaskets, and junction boards for dry-type and railway transformers
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Switchgear & Circuit Breakers: Arc barriers, arc chutes, and disconnector components benefiting from 240+ second arc resistance
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Generator Insulation: Structural insulation parts in high-voltage generators
Performance Benefits:
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Maintains dielectric integrity at elevated operating temperatures
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Self-extinguishing properties prevent fire propagation
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Excellent dimensional stability prevents creep and loosening
2. Aerospace & Automotive Industries
Core Applications:
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Engine Gaskets & Seals: Thermal stability up to 250°C for short-term exposure
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Electrical System Components: High-temperature wiring insulation and connector supports
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Power Electronics: Insulation for EV/HEV battery management systems and inverters
Performance Benefits:
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Superior chemical resistance to oils, fuels, and hydraulic fluids
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Lightweight yet mechanically robust construction
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Consistent performance in vibration-intensive environments
3. Heavy Industrial Equipment
Core Applications:
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Furnace & Oven Insulation: Protective covers and thermal barriers
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Welding Equipment: Arc shields and electrode insulation
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Conveyor Systems: High-temperature belt guides and wear strips
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Power Supply Units: Insulation wraps for industrial transformers and rectifiers
Performance Benefits:
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Withstands thermal cycling in harsh manufacturing environments
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Resistant to industrial chemicals and cleaning solvents
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Machinable to tight tolerances for custom components
4. Railway & Transportation
Core Applications:
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Traction Motor Insulation: Slot liners and phase insulation for diesel-electric and pure electric locomotives
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Auxiliary Power Units: Insulation components in train power systems
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Signaling Equipment: High-voltage insulation for trackside transformers
Performance Benefits:
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Complies with railway fire safety standards
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Excellent moisture resistance for outdoor applications
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Long service life reduces maintenance downtime
Processing & Fabrication Guidelines
Machining:
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Can be cut, drilled, milled, and turned using standard carbide tooling
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Use dust extraction systems; wear appropriate PPE
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Recommended cutting speed: 200-300 m/min with coolant
Forming:
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Not recommended for complex bending (thermoset material)
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Minor forming possible at elevated temperatures (>150°C)
Assembly:
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Compatible with epoxy, silicone, and polyurethane adhesives
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Mechanical fastening: Use insulated fasteners to prevent galvanic corrosion
Frequently Asked Questions
Q1: What is the difference between G7 and other NEMA grades (G10, G11)?
A: G7 uses silicone resin, offering superior thermal stability (Class H, 180°C) and arc resistance compared to epoxy-based G10/G11 (Class F, 155°C). However, G10/G11 have higher mechanical strength and better dimensional stability. G7 is preferred for high-temperature electrical applications, while G10/G11 are used for structural electronic applications like PCBs.
Q2: Can G7 laminate be used outdoors?
A: Yes. G7 exhibits excellent moisture resistance and maintains electrical properties after water immersion. It’s suitable for outdoor transformer and switchgear applications. For UV-exposed applications, consider UV-stabilized coatings.
Q3: What are the standard sheet sizes and thickness tolerances?
A: Standard sizes: 1020×1220mm, 1020×2040mm, 1000×2000mm. Thickness range: 0.5mm to 100mm. Standard tolerance: ±0.1mm for sheets ≤10mm, ±0.2mm for sheets >10mm. Custom sizes available upon request.
Q4: How does G7 perform under high humidity?
A: G7 maintains excellent dielectric properties in humid conditions. Volume resistivity after immersion remains ≥10⁸ Ω·cm, and dielectric constant change is minimal (<15%). It’s ideal for tropical and marine applications.
Q5: Is G7 material RoHS and REACH compliant?
A: Yes. Our G7 laminate is free from restricted substances and complies with RoHS 3 (2015/863) and REACH regulations. Material certification available upon request.
Q6: What is the minimum order quantity (MOQ)?
A: Standard sheets: 100kg minimum. Custom cut parts: 500kg per size. Sample sheets (300×300mm) available for testing purposes.
Ordering Information
Standard Specifications:
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Product Code: SIDA-G7-3250
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Material: Silicone resin + alkali-free glass cloth
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Thermal Class: H (180°C)
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Color: White/Cream
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Certification: UL94 V-0, IEC 60893, NEMA G7
Available Formats:
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Full sheets (standard sizes)
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Cut-to-size panels
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Machined components (per customer drawings)
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Punch-formed parts
Packaging: Palletized with PE film wrapping and edge protection. Moisture barrier bags available for export.
Lead Time: 15-20 business days for standard orders; expedited service available.
Technical Support & Customization
SIDA provides comprehensive technical support including:
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Material selection consultation
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Custom thickness and dimension manufacturing
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Machining and fabrication services
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Application-specific testing
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UL/CE certification assistance
Contact our engineering team for detailed technical drawings, CAD files, or application-specific recommendations.