Durostone® UPM 203
Durostone UPM 203 is a polyester (UP) resin composite reinforced with an E-glass roving mat, conforming to UPGM 203 per EN 60893 and rated UL 94 V-0 at 3 mm. The material delivers 130 MPa flexural strength perpendicular to lamination, 12 kV/mm electric strength under oil at 90°C, a Comparative Tracking Index of 600, and Insulation Class F. Engineered for switchgear, renewable energy, and electrical insulating applications.
Key Properties
- Density: 1.85 g/cm³ (ISO 1183)
- Tensile Strength ∥: 70 MPa (ISO 527)
- Flexural Strength ⊥: 130 MPa (ISO 178)
- Flammability: UL 94 V-0 / 3 mm
- Electric Strength 90°C Under Oil ⊥: 12 kV/mm (IEC 60243)
- Comparative Tracking Index: 600 (IEC 60112) — Insulation Class F (IEC 60085)
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- Specifications
- Applications
- General Info
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Mechanical Properties
| Property | Value | Test Method |
| Density | 1.85 g/cm³ | ISO 1183 |
| Flexural Strength ⊥ | 130 MPa | ISO 178 |
| Modulus of Elasticity in Flexion ⊥ | 9,000 MPa | ISO 178 |
| Compressive Strength ⊥ | 250 MPa | ISO 604 |
| Tensile Strength ∥ | 70 MPa | ISO 527 |
| Impact Strength ∥ (Charpy) | 40 kJ/m² | ISO 179 |
Thermal Properties
| Property | Value | Test Method |
| Flammability | V0 / 3 mm | UL 94 |
| Coefficient of Linear Expansion ∥ | 15 – 30 × 10⁻⁶ × K⁻¹ | TMA (Mettler) |
| Temperature Index | 155 (T.I.) | IEC 60216 |
| Insulation Class | F | IEC 60085 |
Physical Properties
| Property | Value | Test Method |
| Water Absorption (4 mm thickness) | 0.2% | ISO 62 |
Electrical Properties
| Property | Value | Test Method |
| Electric Strength 90°C Under Oil ⊥ | 12 kV/mm | IEC 60243 |
| Electric Strength 90°C Under Oil ∥ | 75 kV/25 mm | IEC 60243 |
| Relative Permittivity (50 Hz) | 4.5 (εᵣ) | IEC 60250 |
| Comparative Tracking Index | 600 (CTI) | IEC 60112 |
| Insulation Resistance After 24 h Water Immersion | 5 × 10⁸ Ω | IEC 60167 |
Flame & Fire Performance
| Property | Value | Test Method |
| Flammability Rating | V0 at 3 mm | UL 94 |
⊥ = perpendicular to the lamination | ∥ = parallel to the lamination
Compliance
- UPGM 203 per EN 60893 — Compliant
- UL 94 — Compliant (V-0 at 3 mm)
- IEC 60216 — Compliant (Temperature Index 155)
- IEC 60085 — Compliant (Insulation Class F)
- IEC 60243, IEC 60250, IEC 60112, IEC 60167 — Compliant (test standards)
- ISO 1183, ISO 178, ISO 604, ISO 527, ISO 179, ISO 62 — Compliant (test standards)
- Switchgear insulation panels and barriers
- Renewable energy electrical insulation components
- Electrical insulating components for the electrical industry
- Generator and motor insulation parts
- Flame-retardant insulation laminates for high-tracking environments
Common industries: switchgear, renewable energy, electrical, and generator and motor manufacturing.
Durostone UPM 203 is a polyester resin composite reinforced with an E-glass roving mat, sitting within the Durostone family of fiber-reinforced electrical insulation laminates. It conforms to UPGM 203 per EN 60893 and is engineered for switchgear, renewable energy, electrical insulating, and generator and motor applications where flame retardancy, tracking resistance, and reliable insulation behavior are required.
Mechanical performance includes 1.85 g/cm³ density, 130 MPa flexural strength perpendicular to lamination, 9,000 MPa modulus of elasticity in flexion, 250 MPa compressive strength perpendicular, 70 MPa tensile strength parallel, and 40 kJ/m² Charpy impact strength parallel.
Thermally, the material is rated UL 94 V-0 at 3 mm flammability, with a Temperature Index of 155, Insulation Class F per IEC 60085, and a coefficient of linear expansion parallel to lamination of 15–30 × 10⁻⁶ × K⁻¹.
Dielectrically, UPM 203 provides 12 kV/mm perpendicular and 75 kV/25 mm parallel electric strength under oil at 90°C, relative permittivity εᵣ of 4.5 at 50 Hz, a Comparative Tracking Index of 600, and 5 × 10⁸ Ω insulation resistance after 24 h water immersion. Water absorption at 4 mm thickness is 0.2%.
Compliant with UPGM 203 per EN 60893, UL 94 V-0 at 3 mm, ISO 1183, ISO 178, ISO 604, ISO 527, ISO 179, ISO 62, IEC 60216, IEC 60085, IEC 60243, IEC 60250, IEC 60112, and IEC 60167.
What differentiates Durostone UPM 203 from other glass-mat polyester laminates?
UPM 203 conforms to UPGM 203 per EN 60893 and combines UL 94 V-0 flame retardancy at 3 mm with a Comparative Tracking Index of 600 — the highest CTI class — and Insulation Class F. That combination of flame rating and tracking resistance is the defining feature for switchgear and renewable energy insulation, where surface tracking and ignition risk must both be controlled.
Why does Comparative Tracking Index matter for this material?
CTI measures a material's resistance to surface conductive paths forming under wet or contaminated electrified conditions. UPM 203 is rated CTI 600 per IEC 60112, the top performance band, which is why it is specified for switchgear and high-voltage insulation where surface tracking is a primary failure mode. The high CTI is paired with 12 kV/mm dielectric strength perpendicular and 75 kV/25 mm parallel under oil at 90°C.
What is the operating temperature classification for UPM 203?
The material has a Temperature Index of 155 per IEC 60216 and is rated Insulation Class F per IEC 60085.
Is UPM 203 suitable for switchgear and flame-rated electrical environments?
Yes. UPM 203 is rated UL 94 V-0 at 3 mm, conforms to UPGM 203 per EN 60893, and carries Insulation Class F with CTI 600, making it suitable for switchgear, renewable energy, and electrical insulating components where flame retardancy and tracking resistance are required.
How should UPM 203 be specified?
Specify grade (Durostone UPM 203), thickness, sheet dimensions, flame rating (UL 94 V-0 at 3 mm), CTI class, dielectric performance requirements, thermal class (Insulation Class F / Temperature Index 155), dimensional tolerances, and finished format.
