Electrical Pressboard

High density electrical pressboard has greater tightness, smaller shrinkage and good evenness. It is mainly used in transformers, capacitors, mutual inductors and other equipment (oil gap pad for cake winding, partition, cardboard tube, corrugated paper, iron yoke insulation, clip insulation and end insulation winding clamp plate, etc.).

Product standard：GB/T19264.3-2003 IEC60641-3-1992

Number

Index name

Unit

Electrical pressboard

High density board

1mm

2mm

3mm

4mm

5mm

≤1.6mm

>1.6～3.0mm

>3～6.0mm

>1.6～8.0mm

Index

1

Thickness & tolerance

%

±7.5

±5.0

±7.5

±5.0

2

Apparent density

g/m2

1.0～1.2

1.0～1.2

1.10～1.25

1.15～1.30

1.20～1.30

3

Moisture content

%

≤8

≤6.0

4

Water extract PH

—

6.5-8.5

5

Ash content

%

≤1.0

6

Oil absorbency

%

≥10

≥9

7

Contamination for transformer oil

No pollution

8

Tensile strength

MD（Longitudinal ）

N/10mm

≥110

≥105

CD（transverse）

≥80

≥85

≥80

≥80

9

Elongation

MD（Longitudinal）

%

≥7.0

≥3.0

CD（transverse）

≥9.0

≥4.0

10

Shrinkage

MD（Longitudinal）

%

≤0.7

≤0.5

CD（transverse）

≤1.0

≤0.7

(Thickness)

≤5.0

≤5.0

11

Electric strength

In air

KV/mm

≥10

≥11

In Oil

≥40

≥30

≥25

≥40

≥35

≥35