How does the tri-cone bit work?

the breaking effect of tri-cone bit on rock

the main way-impact, crushing effect:

the impact force and static pressure of its longitudinal oscillation all lead to the impact and crushing effect of the teeth on the ground, forming a volume broken pit.

auxiliary method-sliding, shearing action:

the radial and tangential movement on the teeth caused a shearing effect on the downhole, fragmenting the rock between the teeth.

erosion effect of jet:

the rapid jet ejected through the nozzle has an impact effect on the rock in the well, and assists in the fragmentation of the rock.

the working principle of the tri-cone bit:

it is under the effect of weight-on-bit and spinning of the drill string. after the teeth are crushed and the rock is eaten, a certain amount of slippage occurs at the same time to shear the rock. when it is rolling at the bottom of the well, the teeth on it will sequentially impact and press into the formation. this effect can crush a part of the bottom rock, and at the same time rely on its sliding to weaken the shearing effect of the teeth. the remaining rocks in between caused the rock at the bottom of the well to be completely broken and the wellbore was extended.