The basic raw material used for manufacturing the Core / Lamination is Cold Rolled Grain Oriented Steel (CRGO) steel. This CRGO steel is imported from reputed overseas mills in various grades of different permeability. Basically, there are many types of CRGO Steel e.g. 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 or in form of slits.
RGO 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, 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 and ZDMH.