Wound Cores CRGO Steel and Transformer Laminations Raw Materials

Cold Rolled Grain Oriented Steel (CRGO) steel is used for manufacturing for Laminations and Wound Cores

The basic raw material used for manufacturing both the Laminations and Wound Cores is Cold Rolled Grain Oriented Steel (CRGO) steel. This CRGO steel are imported from reputed overseas mills in various grades of different permeability. Basically, there are many types of CRGO Steel eg. M-3, M-4, M-5 and M-6 grade and HI-B Material.

These raw materials are imported in forms of coils having standard width of 750/1100 mm or in form of slits.

CRGO material has the least figure of maximum core loss in the rolling direction. With the increased shearing angle to the rolling direction, the core loss at any particular flux density goes up and becomes generally highest in the transverse direction. Because of this it is possible to use CRGO in static electrical machines which include all types of power transformers, distribution transformers, reactors, audio transformers etc.

Manufacturing Mills of CRGO Steel do guarantee the core loss figure at flux density of 1.5 Tesla for conventional grain oriented steel and at 1.7 Tesla in case of HI-B and HI-B-LS steel.

The grades of material popularly used are M-3, M-4, M-5 and M-6. We also use, for special requirements of the customers, HI-B Material designated as MOH, TRAN-COR, H, ZH, ZDKH, ZDMH.

At VSPL, we pay special attention while processing of the raw material like:

• All the incoming materials are checked for its thickness, grade insulation and watt loss.
• We use Tungsten Carbide Tipped tools for cutting in order to minimize burr level.
• Also quality control checks are carried out right through manufacturing process at regular half-intervals on every machine and the record is maintained separately.