The LW-8229A/LW-8229B is a pre-mixed, filler-loaded epoxy system designed for medium/high-voltage insulation (10-35kV). Combining modified BPA epoxy (LW-8229A) and anhydride hardener
(LW-8229B) with integrated fillers, it delivers superior crack
resistance, V1 flammability rating (UL94), and H-class thermal
endurance (180°C). Optimized for vacuum casting and APG processes
in transformers, CTs, and terminal posts.
Key Features & Advantages
| Feature | Advantage |
|---|
| Pre-Mixed Fillers | Simplified processing, consistent dispersion |
| V1 Flammability Rating | Enhanced fire safety for critical electrical components |
| Thermal Class H (IEC 60085) | Stable performance up to 180°C |
| APG & Vacuum Casting Ready | Flexible production integration |
| High Arc Resistance | 181-198 sec (IEC 61621) |
| Low Water Absorption | 0.10-0.20% (23°C/10d) |
| Dual-Process Compatibility | Adapts to APG or vacuum workflows |
Applications
Ideal for sealed electrical insulation:
10-35kV terminal posts & bushings
Dry-type transformers & current transformers
Switchgear insulation components
HV sensor encapsulation
Grid protection devices
Key Performance Data
*Cured system: LW-8229A/LW-8229B = 100:100 | Cure: 140°C×4h +
150°C×12h*
Mechanical & Thermal Properties
| Property | Value | Standard |
|---|
| Flexural Strength | 90-130 MPa | ISO 178 |
| Tensile Strength | 55-85 MPa | ISO 527 |
| Impact Strength | 8-15 kJ/m² | ISO 179 |
| Glass Transition (Tg) | 105-120°C | ISO 11357-2 |
| Thermal Conductivity | 0.8-0.9 W/m·K | ISO 8894-1 |
| Decomposition Temp | >320°C | ASTM E2402 |
Electrical & Safety Properties
| Breakdown Strength | ≥25 kV/mm | IEC 60243-1 |
| Volume Resistivity | 10¹⁵ Ω·cm | IEC 62631-3-1 |
| Tracking Resistance | ≥600 V | IEC 60112 |
| Dielectric Constant | 3.0-4.0 (50Hz) | IEC 60250 |
| Flammability | V1 (UL94) | UL94/GB/T2408 |
| Hydrophobicity | HC1 Class | IEC 62073 |
Frequently Asked Questions (FAQ)
Q1: Are fillers pre-mixed in this system?
A: Yes! Both LW-8229A (resin) and LW-8229B (hardener) contain
pre-dispersed fillers, ensuring uniform properties and reduced
mixing complexity.
Q2: What curing cycle is recommended?
A: For vacuum casting:
Cure: 75°C/4-5h → 95°C/2h → 115°C/4-6h → Post-cure 150°C/12h
For APG: Post-cure 130-150°C/10-12h after molding.
Q3: Why choose V1 flammability over HB?
A: V1 rating offers superior fire resistance for high-risk
applications like transformers and terminal posts, meeting stricter
safety standards.
Q4: Is silica filler adjustable?
A: Fillers are pre-loaded. For custom ratios, contact Shanghai
Wenyou for tailored solutions.
