The d-exponent and the dc- exponent are calculated and displayed / printed automatically after some of the parameters are entered manually after the following formulas:
and
| d | = | weight on bit exponent |
| P | = | penetration rate (ft/hr) |
| K | = | formation drill ability |
| N | = | rotary speed (rpm) |
| e | = | rotary speed exponent |
| W | = | weight on bit (lb) |
| D | = | bit diameter (in) |
| dc | = | corrected d exponent |
| MW1 | = | normal formation pressure gradient (lb/gal) |
| MW2 | = | actual mud weight used (lb/gal) |
Normal dc-exponent, Corrected dc-exponent, Formation pore pressure
are given out after
d / K / e / MW1
are entered manually and the other parameters are collected via GEOCOMP-system.
