Insulation pressboard Introduction:
Insulation pressboard is made of 100% sulfate wood pulp and has high density (similar to T4). It has excellent properties of very flat, highest mechanical and electrical strength and little shrinkage. It is used in oil-immersed power transformer. Pressboard standard: IEC 641-3-1
Pressboard Thickness: 1.0-8.0mm
Size (mm): 6300*3200, 6300*1600, 4200*3200, 4200*1600, 3200*3150, 3200*2100, 2000×1000 1000×1000
|
Index. |
Unit |
Values | ||||
| ≤1.6 | ＞1.6～3.0 | ＞3.0 | ||||
| 1 | Nominal thickness tolerance | % | ≤10（±） | |||
|
2 |
Nominal Grammage |
g/cm3 |
1.00～1.20 | 1.00～1.25 | 1.15～1.30 | |
| 3 | Shear strength ,M.D. | Mpa | ≥100 | ≥105 | ≥110 | |
| 4 | Shear strength, C.M.D. | Mpa | ≥75 | ≥80 | ≥85 | |
| 5 | Elongation (M.D.) | % | ≥3.0 | |||
| 6 | Elongation (C.M.D.) | % | ≥4.0 | |||
| 7 | Shrinkage | % | ≤10.0 | ≤7.5 | ≤5.0 | |
|
8 |
Shrinkage which would resume |
% |
≥45 |
≥50 |
≥50 |
|
|
11 |
Shrinkage: |
M.D. |
% |
≤0.5 | ||
| C.M.D. | ≤0.7 | |||||
| Thickness direction | ≤4.0 | |||||
| 12 | Moisture content | % | ≤6.0 | |||
| 13 | Ash content | % | ≤1.0 | |||
| 14 | Electrical conductivity of aqueous extract | ms/m | ≤1.6 | ＞1.6～3.0 | ＞3.0 | |
| 15 | Aquesous extract (PH) | — | 6～9 | |||
| 16 | Oil absorption | % | ≥11.0 | ≥9.0 | ≥7.0 | |
| 17 | Voltage resistant strength(In air) | MV/m | ≥12 | ≥11 | ≥10 | |
| 18 | Voltage resistant strength(In oil) | MV/m | ≥40 | ≥35 | ≥30 | |
