Transformer presspaper, also known as Kraft paper, is made from high-purity 100% sulphate wood pulp through high-pressure processing. It features high chemical purity, excellent mechanical strength, and maintains both mechanical and electrical properties after oil immersion. As a surface insulation material, it offers high voltage resistance and strong oil impregnation capability. With low permittivity and high oil absorption, it provides an optimal balance of electrical and mechanical insulation. It is widely used in coil winders, motors, transformers, laminates, as well as in oil-immersed transformers, reactors, capacitors, and switches.
Insulation Paper
Sulphate Wood Pulp
A
0.05mm-8.0mm; or customized
625mm-1350mm or customized
1000mm & 1150mm, or customized
Original pulp color; brown, cyan, red
Insulation Protection/ oil-immersed power transformer
Thermal resistance
Arc resistance
Chemical corrosion resistance
Moisture resistance.
● Transformer board is widely used in Inductor , Reactor , Power transmission and Transformation equipments . Our transformer board has higher mechanical and electrical strength , higher tensile strength , lower compressibility and bending performance .
| Insulation Presspaper/Pressboard | |||||
|---|---|---|---|---|---|
| Properties | Unit | ≤1.6 | 1.6～3.0 | ＞3.0 | |
| Nominal thickness tolerance | % | ≤10（±） | |||
| Nominal Grammage | g/cm³ | 1.00～1.20 | 1.00～1.25 | 1.15～1.30 | |
| Shear strength ,M.D. | Mpa | ≥100 | ≥105 | ≥110 | |
| Shear strength, C.M.D. | Mpa | ≥75 | ≥80 | ≥85 | |
| Elongation (M.D.) | % | ≥3.0 | |||
| Elongation (C.M.D.) | % | ≥4.0 | |||
| Shrinkage | % | ≤10.0 | ≤7.5 | ≤5.0 | |
| Shrinkage which would resume | % | ≥45 | ≥50 | ≥50 | |
| M.D. | ≤0.5 | ||||
| C.M.D. | ≤0.7 | ||||
| Shrinkage | Thickness direction | % | ≤4.0 | ||
| Moisture content | % | ≤6.0 | |||
| Ash content | % | ≤1.0 | |||
| Electrical conductivity of aqueous extract | ms/m | ≤1.6 | ＞1.6～3.0 | ＞3.0 | |
| Aquesous extract (PH) | — | 6～9 | |||
| Oil absorption | — | ≥11.0 | ≥9.0 | ≥7.0 | |
| Voltage resistant strength(In air) | MV/m | ≥12 | ≥11 | ≥10 | |
| Voltage resistant strength(In oil) | MV/m | ≥40 | ≥35 | ≥30 | |
The above values are for reference only and are taken from the average test results, do not represent complete consistency with the actual performance of the material.
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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