| IADC | WOB | RPM | Application |
| (KN/mm) | (r/min) |
| 111/114/115 | 0.3-0.75 | 200-80 | very soft formations with low compressive strength and high drill
ability, like clay, mudstone, chalk |
| 116/117 | 0.35-0.8 | 150-80 | very soft formations with low compressive strength and high drill
ability, like clay, mudstone, chalk |
| 121 | 0.3-0.85 | 200-80 | soft formations with low compressive strength and high drill
ability, like mudstone, gypsum, salt, soft limestone |
| 124/125 | 180-60 |
| 131 | 0.3-0.95 | 180-80 | soft to medium formations with low compressive strength, like
medium, soft shake, medium soft limestone, medium soft sandstone,
medium formation with harder and abrasive interbeds |
| 136/137 | 0.35-1.0 | 120-60 |
| 211/241 | 0.3-0.95 | 180-80 | medium formations with high compressive strength, like medium, soft
shake, hard gypsum, medium soft limestone, medium soft sandstone,
soft formation with harder interbeds. |
| 216/217 | 0.4-1.0 | 100-60 |
| 246/247 | 0.4-1.0 | 80-50 | medium hard formation with high compressive strength, like hard
shale, limestone, sandstone, dolomite |
| 321 | 0.4-1.0 | 150-70 | medium abrasive formations, like abrasive shale, limestone,
sandstone, dolomite, hard gypsum, marble |
| 324 | 0.4-1.0 | 120-50 |
| 437/447/435 | 0.35-0.9 | 240-70 | very soft formations with low compressive strength and high drill
ability, like clay, mudstone, chalk, gypsum, salt, soft limestone |
| 517/527/515 | 0.35-1.0 | 220-60 | soft formations with low compressive strength and high drill
ability, like mudstone, gypsum, salt, soft limestone |
| 537/547/535 | 0.45-1.0 | 220-50 | soft to medium formations with low compressive strength, like
medium, soft shake, medium soft limestone, medium soft sandstone,
medium formation with harder and abrasive interbeds |
| 617/615 | 0.45-1.1 | 200-50 | medium hard formation with high compressive strength, like hard
shale, limestone, sandstone, dolomite |
| 637/635 | 0.5-1.1 | 180-40 | hard formation with high compressive strength, like limestone,
sandstone, dolomite, hard gypsum, marble |
| Note: Above limitts of WOB and RRPM should not be used
simultaneously |
