Bit type | IADC Code | Applicable formation | Main characteristics of the bit | Recommended parameters | |
Cutting structure | Normal WOB KN/mm(bit dia.) | Rotary Speed(rpm) | |||
THA116 | 116 | Very soft with low compressive strength and high drillability.such as soft shale.slay and salt bed,etc. | Hardfaced looth surface and gage,high cutter exposure | 0.350.90 | 15080 |
THA117 | 117 | Hardfaced tooth surface and gage,high cutter exposure and the gage fitted with compacts | |||
THA126 | 126 | Soft with low compressive strength and high drillabiliyt .such as shale,clay,salt bed and soft limestone,etc. | Hardfaced looth surface and gage,high cutter exposure | 0.351.00 | 15070 |
THA127 | 127 | Hardfaced tooth surface and gage,high cutter exposure and the gage fitted with compacts | |||
THA136 | 136 | Soft to medium soft with low compressive strength or soft with harder stringers. such as hard gypsolyte.soft limestone and sandstone,etc | Hardfaced gage and all tooth surfaces | 0.351.05 | 12060 |
THA137 | 137 | Hardfaced gage and all tooth surfaces,and the gage fitted with compacts for enhanced gage protection | |||
THA216 | 216 | Medium hard with relatively higher compressive strength and hard stringers,such as hard shale,sandstone and limestone,etc. | Hardfaced gage and all tooth surfaces | 0.501.20 | 9050 |
THA217 | 217 | Hardfaced gage and all tooth surfaces,and the gage fitted with compacts for enhanced gage protection | 0.501.20 | 10050 | |
THA417 | 417 | Very soft with low compressive strength and high drillability.such as shale,caly,sandstone and conglomerate,etc. | Large dia,offset crested scoop compacts in inner row,wgdge compacts in outer row | 0.350.90 | 14070 |
THA437 | 437 | Very soft with low compressive strength and high drillability,suchasshale claym sandstone,soft limestone,etc. | Large dia,offset crested scoop compacts in inner row,wgdge compacts in outer row | 0.350.95 | 14060 |
