Cold-rolled grain-oriented magnetic sheets

Cold-rolled grain-oriented magnetic sheets

In contrary to non-grain-oriented magnetic sheets, in grain-oriented ones crystals are oriented in the plate’s length direction. Accordingly they have lesser loss and higher magnetic saturation level and applied when the core loss has more significant importance and flux can be conducted in the length direction like grid transformers and some induction furnace yokes.

It is noteworthy telling that in the recent decade with increasing importance of the power loss and environmental issues, an improved type of CRGO sheet is proposed by the producers which has lower loss in comparison to the previous CRGO ones. This type, called low-loss magnetic core, is mostly used in power transformers of MV and HV levels. low-loss magnetic core sheets are in turn divided in 2 categouries named normal low-loss cores and ultra-low-loss cores. the later one, sometimes called Hi-B core sheets.

Considering higher cost of low-loss magnetic core sheets and magnetically low operating points of induction yokes, these core sheets are not used in induction furnace yokes.

Below table presents the specifications and main parameters for various grades of normal and low-loss CRGO magnetic core sheets.