Working principle
1) Revolution of drill bit The revolution speed of the drill bit is the rotation speed of the turntable or thedown hole power drilling tool. When the drill bit revolves, the cone also rotates around the axis of the drill bit. The linearspeed of each row of teeth on the cone rotating around the axis of the drill bit is different, and the linear speed of the outerrow of teeth is the largest. 2) Rotation of the drill bit When the drill bit rotates, the counterclockwise rotation of the conearound the axis of the tooth palm is called auto rotation. The rotation speed of the cone is determined by the revolution speed of the drill bit, and is related to the effect of the teeth on the bottom of the well. 3) Longitudinal vibration (axial vibration) impact crushing of the drill bit The change of the position of the wheel center makes the drill bit reciprocate up and down along the axial direction, which is the longitudinal vibration of the drill bit, which is related to the drill bit structure parameters such as tooth height and tooth spacing and lithology. Soft strata have small amplitudes, while hard strata have large amplitudes. The vibration frequency is proportional to the number of teeth and the speed of the cone.
4) Sliding shear breaking action of drill bit Crushing different types of rock requires different slippage of the drill bit, which is determined by the structural parameters of the drill bit. In soft formations, bit slippage is large, and in hard formations, it should be as small as possible or not slipped.
| Basical Specification | |
| Size of Rock Bit | 5 3/4" |
| 146.1mm | |
| Bit Type | Steel Tooth Tricone Bit/ Milled tooth Tricone Bit |
| Thread Connection | 3 1/2 API REG PIN |
| IADC Code | IADC 216 |
| Bearing Type | Journal Sealed Roller Bearing |
| Bearing Seal | Rubber Seal |
| Heel Protection | Unvailable |
| Shirttail Protection | Available |
| Circulation Type | Mud Circulation |
| Drilling Condition | Rotary drilling,high temp drilling,deep drilling,motor drilling |
| Nozzles | Central Jet Hole |
| Operating Parameters | |
| WOB (Weight On Bit) | 9,879-27,904 lbs |
| 44-124KN | |
| RPM(r/min) | 60~180 |
| Formation | Soft to medium formations with high compressive strength, such as mudstone,gypsum,salt,soft limestone ,etc. |
5 3/4" TCI tricone bit is widely used in water well drilling, exploration, HDD pilot hole, foundation piling, it has a central jet hole design, so it is also workable for reverse circulation drilling.The bearing is sealed, the working life is much longer than open bearing roller bits.
