8 1/2 inch PDC bit
| Number of Blades | 6 |
| Primary Cutter Size | 13mm |
| Nozzle Qty. | 6NZ |
| Gauge Length | 2.2 Inch |
| RPM (r/min) | 70~270 |
| WOB(KN) |
25~115 |
| Flow Rate (lps) | 22~35 |
| Application |
Medium and compact formation with very high but no abrasive layer,such as limeston, sandstone,shale,etc. |
**Matrix-body bit
Matrix-body PDC bits are commonly preferred over steel-body bits for environments in which body erosion is likely to cause a bit to fail. For diamond-impregnated bits, only matrix-body construction can be used.
** Steel-body bits
The strength and ductility of steel give steel-bit bodies high resistance to impact loading. Steel bodies are considerably stronger than matrix bodies.A beneficial feature of steel bits is that they can easily be rebuilt a number of times because worn or damaged cutters can be replaced rather easily. This is a particular advantage for operators in low-cost drilling environments.
| Rock hardness and bit selection | |||||
| Cone bit IADC code | PDC | Formation | Rock Types | Compressive strength (Mpa) | ROP(m/h) |
| 111/124 | M/S112~M/S223 | Very soft: low viscosity, low compressive strength. |
clay siltsone sandstone |
<25 | >20 |
| 116/137 | M/S222~M/S323 | Soft: the formation is soft with low compressive strength and good drillability. |
Clay rocks lignite sandstone |
25~50 | 10~20 |
| 417/527 | M/S323~M/S433 | Medium soft: weak to medium, low compressive strength. |
Clay rocks sandstone siltstone anhydrite limestone |
50~75 | 5~15 |
| 517/537 | M322~M443 | Medium to hard formation with high compressive strength and poor abrasion resistance. |
mudstone Sandy limestone shale |
75~100 | 2~6 |
| 537/617 | M422~M444 | Medium hardness: hard, dense formation with high compressive strength and moderate wear. |
The marble granite Hard shale anhydrite sandstone dolomite schist |
100~200 | 1.5~3 |
