Click here to view or download the Application Ranges Chart in .pdf format. (38kb)
The four major types of cutting media that are used on mineral exploration bits each have an appropriate range of application. Note that surface-set natural diamond has been excluded from this data as this type of cutting media is considered to be a second choice to thermally stable polycrystalline (TSP) elements. Surface-set natural diamond and TSP elements have approximately the same range of application. Surface-set diamond should only be selected in cases where TSP is unavailable as cutting media for a particular size of core bit.
The various numerical values that are used to describe the geological formations called out in the Application Ranges Chart are defined as follows:
DCDMA Code is a reference number that is used as a comparison between different manufacturers coding systems for impregnated diamond core bits.
Mohs Hardness is a method of quantifying the hardness of geological materials by means of a simple “scratch test”. The units of hardness are expressed as numbers ranging from 1 to 10, each of which is represented by a mineral that can be made to scratch any other mineral bearing a lower number. In ascending order of hardness, the minerals are ranked as follows: Talc (1), Gypsum (2), Calcite (3), Fluorite (4), Apatite (5), Orthoclase (6), Quartz (7), Topaz (8), Corundum (9) and Diamond (10).
UCS (Uniaxial Compressive Strength) is a test that is normally performed in a laboratory and is a measurement of the ultimate compressive stress that a sample of rock can withstand before failure under an increasing point load. This test is an objective means of quantifying the strength of a geological material and therefore its drillability.