Professional TCI Tricone Bit / Roller Cone Bit For Medium Hard Formation

Tricone Rock Bit , Medium Hard Formation , TCI Bit , Roller Cone Bit

RECOMMENDED DRILLING PARAMETERS FOR APPLICATION

ROLLER CONE BIT CONE DESIGN

All three cones have the same shape except that the No. 1 cone has a spear point. One of the basic factors to be decided, in the design of the cones, is the journal or pin angle . The journal angle is formed between the axis of the journal and the horizontal. Since all three cones fit together, the journal angle specifies the outside contour of the bit. The use of an oversize angle increases the diameter of the cone and is most suitable for soft formation bits. Although this increases cone size, the gauge tip must be brought inwards to ensure the bit drills a gauge hole. 

One important factor which affects journal angle is the degree of meshing or interfit (i.e. the distance that the crests of the teeth of one cone extend into the grooves of the other). The amount of interfit affects several aspects of bit design.

1. It allows increased space for tooth depth, more space for bearings and greater cone thickness
2. It allows mechanical cleaning of the grooves, thus helping to prevent bit balling
3. It provides space for one cone to extend across the centre of the hole to prevent coring effects
4. It helps the cutting action of the cones by increasing cone slippage.