Approximate Drill Bit Loads and Feeds for Thriftline Drill Bits
Formation Type | Revs per Centimetre | Bit Type | Max Load (tonnes) |
Clay | 10 | AXT | 1.85 |
Coal | 20 | BX | 2.16 |
Shale | 40 | BQ | 2.67 |
Medium Sandstone | 60 | NX | 3.24 |
Basalt Sandstone | 120 | NQ | 4.09 |
Granite | 150 | HQ | 6.14 |
Quartzite | 200 | PQ | 7.84 |
Please note that the maximum load calculations exclude the rod weights and are based on optimum conditions.
It may seem that the faster the drill rotates the Drill bit and the harder it is pushed the faster it will penetrate.
This is only true to a limit as other factors affect Drill bitrotation and pressures.
Limiting Factors: