Grain oriented electrical steel strip is supplied with a thin in- organic coating on the glass film layer formed during annealing. A film thickness of 2 to 5 µm provides good electrical resistance and a high stacking factor.
The coating, which is annealing resistant up to 840 °C, enables wound cores and sheet blanks to be stress relief annealed. The coating is chemically resistant to liquids to which it is typi-cally exposed during the production process and has no effect on the various types of transformer oils.
We offer two types of insulation coatings: the chromium-contain-ing coating and the chromium-free coating. Both coatings are similar from a technological point of view.
|Color deviations are possible, but they have no influence on the properties
|Phosphate on glas film:
|2 µm - 5 µm
|SURFACE INSULATION RESISTANCE
|at room temperatureaccording to IEC 60404-11
|> 10 Ω cm2
|Under inert gas according to IEC 60404-12
|840 °C / 2 h
|Comparison with the designations IEC 60404-1-1
|EC-5-G on EC-2
|Comparison with the designations ASTM A976
|C-5 over C-2
|w.r.t. transformer oil