WOB is broken in the underground rock must have the condition. Their situation to ensure that the methods and the characteristics of the rock crusher, impact straight to the speed and method of drilling their destruction. At the time of construction.
Tricone bit when drilling is the most important parameter, not only helps to have cut into the rock to show its effects, but also minimizes its friction. After double the pressure in the test formula PDC drill different level when the outcome showed that: unlike the rock when the pressure of the resulting increased velocity is not the same.