Since the dawn of time, human beings tried to recognize and reach the underground wealth of our planet, the only difference is the evolution. Nowadays we can operate even in rigid rocks, thanks to the diamond drill hole process.
Diamond drill hole is a logging process, providing engineers and geologists precise, intact, and solid samples of rocks lying hundreds of meters beneath the ground.
This method consists of creating a circular cut in the ground all along the depth needed, using a diamond drill bit. Diamonds are Known as one of the most rigid structures, they are a solid, form of pure carbon, makes them a perfect tool to be used on very hard materials, such as concrete and steel. Once the diamond drill bit is designed, the drilling gets started. This fast rotation drilling is used to destruct the rock no matter how hard it is. It is an environment friendly method that causes no vibration nor damage nearby. However, the drilling must be with proper techniques, respecting the Drill Speed, Drill Pressure and Lubrication limits to prevent the overheat of the drill bit, that can cause serious spalling, fractures problems and material breakage, therefore reducing the life circle of the hole and damaging the samples.
To avoid those potential problems, and as we have variety of material abrasiveness, drill speed must be reduced, so that it can fit every grade of hardness. Also, it is important to reduce the pressure to let the drilling take its normal speed, because increasing pressure will not speed up the cutting, but it will only increase the friction. Moreover, during the drilling operation, and in order to prevent the overheat of the diamond drill bit, we need to lubricate, with water to control the temperature and get rid of the dust. Sometimes the drilling can proceed without water or using small amount of it (such as drilling in fiberglass).
Finally, we extract a continuous, cylindrical sample for geologists to assess. The importance of this method is crucial; therefore, it is one of the important modules in Promine software called DDH. This module allows the mine to manipulate the diamond drill holes, insert information and annotate them easily.
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