There are many manufacturers of tooth bits, and these drill bit factories provide bits of various types and structures. In order to facilitate the selection and use of roller cone bits, the International Association of Drilling Contractors (IADC) has developed a unified worldwide classification standard and numbering method for roller cone bits.
IADC stipulates that each type of drill bit is represented by three digits, and the meaning of each number is as follows:
The first digit indicates the type of tooth and the formation suitable for drilling:
1 - Milling teeth, soft ground;
2 - Tooth milling, medium to medium hard formation;
3 - Milling teeth, hard, abrasive or semi-abrasive formations;
4 - Spare;
5 - Insert teeth, soft to medium stratum;
6 - Insert teeth, medium-hard stratum;
7 - Insert teeth, hard, abrasive or semi-abrasive formation;
8 - Insert teeth, extremely hard, highly abrasive formations.
The second digit indicates that the drilled formation is subdivided into four hardness grades 1, 2, 3, and 4.
The third digit indicates the structural characteristics of the drill:
1 - Unsealed rolling bearings;
2 - T-shaped outer row tooth gauge;
3 - There are insert teeth on the gauge diameter;
4 - Sealed rolling bearing;
5 - Sealed rolling bearing, with insert teeth on the gauge diameter;
6 - Sealed sliding bearing;
7 - Sealed sliding bearing, with insert teeth on the gauge diameter;
8 - Directional well deflection bit;
9 - Other.
Advantages of roller cone bits:
1. The double action of impact and shearing breaks the rock, both the impact of the teeth and the shear caused by sliding, the rock breaking efficiency is high.
2. It is suitable for a wide range of formations and is suitable for drilling in all formations.
3. The self-washing effect of the drill bit is good, and it is not easy to mud pack.
4. Lower cost of drill bit.