3240 Epoxy Phenolic Glass Cloth Laminated Sheet is made of electrical-grade alkali-free glass fiber cloth impregnated with modified epoxy phenolic resin, and produced by hot pressing and curing. 3240 GRADE A: It has good mechanical and dielectric properties with thermostability and moisture resistivity and good machinability. The thermostability class is B. It is widely used in generator, motor, electronic apparatus as insulating material and components. It is also suitable under oil pressure of transformer and wet environment. 3240 Grade B: It provides reliable mechanical strength and electrical insulation performance with stable thermostability in Class B. Compared with Grade A, it is more economical while still maintaining sufficient dielectric properties and moisture resistance for general applications.
YILONG
Epoxy Resin + Phenolic Resin + Fiberglass
Yellow
0.3~100mm
1030mm*1230mm
1030mm*2030mm, 1220mm*2440mm, 1030mm*1030mm
Pallet, Wooden Box
500KG
High mechanical strength at medium and elevated temperatures.
Tensile elongation exceeds 50% under high-temperature conditions.
Excellent resistance to mechanical stress and deformation.
Stable electrical insulation performance.
Insulation resistance up to 10¹² Ω even after water immersion.
High dielectric strength (over 35 kV) when tested parallel to laminations under humid conditions.
Good moisture resistance and environmental stability.
Reliable performance in high-humidity environments.
Good machinability for drilling, milling, and CNC processing.
Suitable for high-voltage electrical insulation applications.
Industry Applications
● Transformers
● Electric motors
● Electrical cabinets and control boxes
● Electric switches
● Household appliances
● Railway and automotive industries
● Computers and medical equipment
Typical Insulation Parts
● Test jigs and fixture PCB testing jigs
● Insulation plates and switch insulation plates
● Polishing gears
● Mould-in cloth and shoe components
● Insulation parts made from bakelite sheet
● Lithium battery pack components
| 3240A & 3240B Technical Data Sheet | |||
| NO. | TEST ITEMS | UNIT | TEST RESULT |
| 1 | Bending Strength Perpendicular to Laminations (A) | MPa | 480 |
| Bending Strength Perpendicular to Laminations (B) | MPa | 340 | |
| 2 | Apparent Bending Elastic Modulus (A) | MPa | 2.2*10^4 |
| Apparent Bending Elastic Modulus (B) | MPa | 2.0*10^4 | |
| 3 | Compressive Strength Perpendicular to Laminations compressive | MPa | 438 |
| 4 | Parallel layer shear strength (A) | MPa | 49.8 |
| Parallel layer shear strength (B) | MPa | 52.7 | |
| 5 | Tensile Strength (A) | MPa | 368 |
| Tensile Strength (B) | MPa | 187 | |
| 6 | Parallel Layer Impact Strength (Simply Supported Beam, Gap) (A) | KJ/m² | 47 |
| Parallel Layer Impact Strength (Simply Supported Beam, Gap) (B) | KJ/m² | 36 | |
| 7 | Vertical Layer Breakdown Voltage (90℃ + 2℃, 25# transformer oil, 20s step by step boost, φ25mm/φ75mm cylinder electrode system) | kV/mm | 21.5 |
| 8 | Parallel Layer Breakdown Voltage (90℃ + 2℃, 25# transformer oil, 20s step by step boost, φ130mm/φ130mm flat plate electrode system) | KV | 90 |
| 9 | Relative Permittivity (50Hz) | - | 4.9 |
| 10 | Insulation Resistance after 24h immersion in water | Ω | 2.3*10^13 |
| 11 | Density | g/cm3 | 1.9-2.1 |
| 12 | Flammability (A) | Grade | V-0 |
| Flammability (B) | Grade | V-1 | |
| 13 | Water Absorption | mg | 36 |
| 14 | Deflection Temperature under Load | ℃ | ＞140 |
| REMARK: 1. NO.5 the sample height is (10.32~10.39) mm; 2. NO.10 the sample thickness is (2.09~2.11) mm; 3. NO.11 the sample size is (100.01~100.07) mm*(25.20~25.31) mm*(5.06~5.20) mm thickness, the electrode spacing is (25.20~25.31) mm; 4. NO.15 the sample size is (18.87~12.99) mm*(4.23~4.28) mm; 5. NO.16 the sample size is (50.39~50.51)mm*(50.37~50.50)mm * (4.24~4.27) mm . |
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Yes, based on drawings or samples.
UL, RoHS, REACH, CE, ISO, etc.
Usually 100 kg or 100 sheets, negotiable.
Yes, common samples free, buyer pays freight.
2-4 weeks after payment.
Yes, including labeling and packaging.
Yes, over 20 years.
T/T 30% deposit, 70% before shipment. Negotiable if supports needed.
Yes, we offer CNC machining.
Manufacturer and Exporter
No.3, Mianzhi Street, Zhucheng, Shandong, China
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