CRGO & CRNGO steel is imported in the form of mother coils from reputed steel producers in Japan, USA, Korea, Germany, Russia, China etc. Each coil conforms to the specifications of Bureau of Indian Standards of quality (IS 3024). Each lot of raw material is accompanied with Mill Test Certificate (MTC) and other relevant chain of documents that can be produced at customer’s request. Then as per the customers requirement the core is prepared using our in house slitting and core manufacturing machinery.
Technical Specifications
| General physical and mechanical properties of CRGO steel | |
|---|---|
| Density | 7.65 g/cm3 |
| Thickness of sheet | 0.23 – 0.35 mm |
| Silicon content | 3-4 % |
| Yield Point (relative to rolling direction) | 0 degrees • 330 N/mm2 90 degrees • 355 N/mm2 |
| Tensile strength | 0 degrees • 348 N/mm2 90 degrees • 412 N/mm2 |
| Elongation | 0 degrees • 11% 90 degrees • 31% |
| Number of bends | 0 degrees • 21 90 degrees • 15 |
| Hardness (Hv) | 204 |
| Stacking factor | 95-98% |
Grade classification of CRGO steel
| Grade (BIS nomenclature) | Grade (conventional nomenclature) | Thickness(mm) | Max. Core loss (W/kg) 50Hz | |
|---|---|---|---|---|
| @1.5T | @1.7T | |||
| 23HP85 | 23ZDKH | 0.23 | 0.60 | 0.85 |
| 23HP90 | 23M0-H | 0.23 | 0.64 | 0.90 |
| 23HP95 | 23M0-H | 0.23 | 0.66 | 0.95 |
| 23HP100 | 23M0-H | 0.23 | 0.68 | 1.00 |
| 23CG110 | M3 | 0.23 | 0.70 | 1.10 |
| 27HP95 | 27ZDKH | 0.27 | 0.66 | 0.95 |
| 27HP100 | 27M0-H | 0.27 | 0.70 | 1.00 |
| 27HP110 | 27M0-H | 0.27 | 0.78 | 1.10 |
| 27CG120 | M4 | 0.27 | 0.85 | 1.20 |
| 27CG130 | M4 | 0.27 | 0.90 | 1.30 |
| 30HP105 | 30M0-H | 0.30 | 0.75 | 1.05 |
| 30CG130 | M5 | 0.30 | 0.90 | 1.30 |
| 30CG140 | M5 | 0.30 | 0.95 | 1.40 |
Tolerance chart for dimensions of CRGO laminations (as per IS 3024)
| Attribute | Attribute Range/Value | Tolerance |
|---|---|---|
| Width | 0 – 100 mm 100 mm – 230 mm 230 mm – 400 mm 400 mm – 750 mm |
+0.00 / -0.15 mm +0.00 / -0.20 mm +0.00 / -0.30 mm +0.00 / -0.50 mm |
| Length | 0 – 350 mm 350 mm – 1,000 mm 1,000 mm – 2,000 mm 2,000 mm – 3,000 mm 3,000 mm – 4,000 mm |
+0.00 / -0.30 mm +0.00 / -0.60 mm +0.00 / -1.00 mm +0.00 / -1.50 mm +0.00 / -2.00 mm |
| Thickness | 0.23 – 0.27 mm 0.30 – 0.35 mm |
+/- 0.025 mm +/- 0.030 mm |
| Mitering Angle | 45 degrees | +/- 5 minutes |
| Burr Height | 0.18 – 0.23 mm 0.23 – 0.30 mm 0.30 – 0.35 mm |
10 microns 15 microns 20 microns |
| Wave Factor | Material width > 150mm, Flatness deviation |
Max. 1.5% of width |
| Edge Camber | Material width > 150mm | Max. 0.8 mm for length of 1.5m |
| Hole Dimension | Up to 34 mm | +/- 0.15 mm |