IS 8125:1976 is the Indian Standard (BIS) for dimensions and materials of cement rotary kilns, components and auxiliaries (dry process with suspension preheater). This standard specifies the principal dimensions, capacities, and materials for the main components of cement rotary kilns operating on the dry process with suspension preheaters. It aims to rationalize the design and manufacturing of kilns and their auxiliaries like shells, tyres, rollers, and gears to promote standardization in the Indian cement industry.
Dimensions and materials of cement rotary kilns, components and auxiliaries (dry process with suspension preheater)
| Parameter | IS Value | International | Source |
|---|---|---|---|
| Kiln Shell Material | Structural Steel as per IS 2062 (e.g., St 42-S) | Boiler plate quality steel like ASTM A516 Gr. 70 or EN 10028 P265GH | ASME BPVC Section VIII / EN 10028 |
| Kiln Slope | 3.5 to 4.0% | Typically 3.0 to 4.5%, depends on pre-calciner presence and process | General Engineering Practice |
| Length/Diameter (L/D) Ratio (Preheater Kiln) | ~16:1 | ~10:1 to 14:1 (for modern kilns with pre-calciners) | Modern OEM Design Data |
| Riding Ring (Tyre) Material | Cast Steel (IS 1030) or Forged Steel (IS 2004) | High integrity forged alloy steel (e.g., 42CrMo4), ultrasonically tested | Manufacturer Specifications / DIN 17200 |
| Refractory in Burning Zone | Magnesite or Chrome-magnesite bricks (as per IS 1527) | High-purity magnesia-spinel bricks (Chrome-free for environmental reasons) | ISO 10081 / Refractory Manufacturer Data |
| Number of Supports | 2 or 3 for kilns up to 1200 tpd | Typically 3 for large modern kilns; 2-support systems are also used | Modern OEM Design Data |