20GK070 Grain-Oriented Electrical Steel — 0.20 mm, 0.70 W/kg
20GK070: what it is and where it belongs
20GK070 carries the same 0.20 mm Hi-B substrate and 1.90 T flux density as the benchmark grade, at 0.70 W/kg. That 0.05 W/kg step is usually the difference between a comfortable Grade 1 certificate and one that only just passes, which is why this grade is our recommended thin-gauge volume item for both oil-immersed and dry-type work.
Typical applications
Grade 1 oil-immersed distribution transformers
Grade 1 dry-type transformers
PV and wind step-up transformers
Compact substations where enclosure size is fixed
Selection and processing notes
Carries both oil-immersed and dry-type Grade 1 designs, so one grade can cover a mixed production line.
Drop to 20GK075 only when the loss margin allows; otherwise the price step rarely pays back.
Supply form and documentation
Supplied as master coil 900–1250 mm wide (508 mm ID, 2–5 t per coil), slit strip from approximately 100 mm at ±0.5 mm width tolerance, or cut-to-length sheets to your lamination size. Standard insulation coating is C5, with C6 heat-resistant and chrome-free options. Every shipment carries an MTC to EN 10204 3.1 stating grade, heat number, measured core loss and flux density, plus packing list and — for export — certificate of origin and a standard cross-reference sheet against IEC 60404-8-7, ASTM A876, EN 10107 and JIS C 2553.
Equivalent designations
Nearest mill equivalent: B20R070. Buyers specifying to IEC or ASTM may treat this grade as the 0.20 mm, 0.70 W/kg tier; the equivalence sheet is supplied with the quotation so the substitution can be written into the purchase order without ambiguity.
