CHARACTERISTICS OF TSD DIAMOND BIT
The cutting action of the tools occurs by cleavage. The cutting edge TSD (thermostable diamond) is made up of cubes or tetrahedrons of different sizes and composed of diamond dust and high thermally stable binders. The inserts are positioned on the cutting surface and are retained by a mixture of tugsteno powders and copper-based alloys which, melting in an infiltration process taking place in the oven, makes the TSD cling to the cutting surface.
During the drilling process, each TSD enters the material to be drilled and a certain amount of material is removed by the rotary effect. This category of products define itself in terms of shape and size of the TSD. NEXUS uses TSD in cubic and tetrahedra form. Tools with cubic TSDs have a good resistance to wear, while tetratedra's TSD tools have a more sharp shape and therefore are more penetrating. This technology is applicable to drill materials with variable hardness from 20 to 150 MPa. Obviously, with the same shape, larger TSDs are more protruding and can remove bigger quantities of material for each revolution, but large TSDs cannot penetrate into hard materials unless they are subjected to high pressures. To better adapt the drilling to the variability of the hardness of the rocks, tools with different TSD sizes are available. In general, hard materials will be processed with small TSDs and softer materials with bigger TSDs. NEXUS produces tools with cubic TSDs with edge 3 mm, 5 mm 6 mm and with tetrahedrons 6x4.5 and 3x2 . It is not enough to identify the type of rock to be drilled to detect the most suitable tool's shape or size, since in the drilling process there are variables having a decisive influence on the cut effectiveness. The depth and the direction of the drilling, the level of fracturing of the rock, the variability of materials within the same hole, the characteristics of the probe (number of revolutions, torque, thrust on the tool), have a decisive influence on the choice of the tool's shape and suitable size. The features must be carefully evaluated before making a choice. In addition to the standard range of shapes and sizes of TSD, NEXUS implements special tools at the customer's request. These tools can use water or air as a drilling fluid for cooling the tool and removing debris.