| IADC | Recommendation | Applicable Formation |
| WOB | RPM |
| 115 | 0.3~0.75 | 200~80 | Very soft formations with low compressive strength and high drillability, such as clay, mudstone, chalk, etc. |
| 125 | 0.3~0.85 | 200~80 | Soft formations with low compressive strength and high drillability, such as mudstone, gypsum, salt, soft shale, soft limestone, etc. |
| 135 | 0.3~0.95 | 180~80 | Soft to medium soft formations with low compressive strength and high drillability, such as medium soft shale, hard gypsum, medium soft limestone, medium soft sandstone, soft formation with harder interbed, etc. |
| 215 | 0.35~0.95 | 180~80 | Medium formations with high compressive strength, such as medium soft shale, hard gypsum, medium soft limestone, medium soft sandstone, soft formation with harder interbed, etc. |
| 435 445 | 0.35~0.95 | 150~60 | Very soft formations with low compressive strength and high drillability, such as clay, mudstone, chalk, gypsum, salt, soft shale, soft limestone, etc. |
| 515 | 0.3~0.8 | 200~80 | Soft formations with low compressive strength and high drillability, such as mudstone, gypsum, salt, soft shale, soft limestone, etc. |
| 535 545 | 0.35~0.9 | 180~80 | Soft to medium formations with low compressive strength, such as medium soft shale, medium soft limestone, medium soft sandstone, medium formation with harder and abrasiver interbed, etc. |
| 615 625 | 0.35~1.0 | 180~80 | Medium hard formations with high compressive strength, such as hard shale, limestone, sandstone, dolomite, etc. |
| 635 | 0.4~1.1 | 150~60 | Hard formations with high compressive strength, such as sandstone, limestone, dolomite, hard gypsum, marble, etc. |
