Tricone bit are widely used for rotary drilling, mostly used to drill big holes and production holes in large quarries, open pit mines, petroleum extraction, and other fields. There are two groups of big rotary drilling: (1) rotary crushing by high-point loading to the rock from three cones, and (2) rotary cutting by shear force from drag bits.
In rotary crushing, the widely used bits are three-cone drill bits covered by many teeth or buttons that rotate freely like planetary gear and crush the rock as the drill bit is rotated. The downward thrust is achieved by the weight of the drill rig itself, and the rotation is applied at the end of the drill pipe. Rotation is provided by a hydraulic or an electric motor, and rotation speeds often vary from 50 to 120 rpm. Compressed air is often used to discharge cuttings from the bottom of the hole. The size of the gap between the drill pipe and the wall of the hole is related to the flushing of drill cuttings. Either a too narrow or a too wide gap will lower the drilling speed.
Rotary drilling is suitable for the borehole sizes from 203 to 445 mm in diameter. So far, rotary drilling has been the dominant method in large open pit mines. One of the disadvantages of rotary drilling rigs is that they are not suitable for drilling an inclined borehole, which is favorable to rock blasting.
Tricone percussion hammer will largely increase the productivity, especially in hard rock conditions. We proud to say that BD DRILL have the ability to provide all the rotary drilling string, from Shock absorb, Drill pipe, Stabilizer, Percussion hammer, Deck bush, Tricone bit.
Post time: May-20-2021