Bored pile roller bit crushes rocks evenly and efficiently, has low construction cost and good hole quality compared to bullet teeth drilling.
1. When the pile roller bit works at the bottom of the pile foundation hole, it not only revolves around the rotary drill rod column, but also rotates around the bored pile roller bit mandrel. Its rotation is in the form of rolling, and the running resistance is small, so it can withstand a large drilling pressure.
2. When the roller bit contacts the rock at the bottom of the pile foundation hole, the contact area between the alloy inserts on the roller bit and the rock is small (fulcrum contact). It is easy to obtain a higher unit axial pressure to crush the rock.
3. When the pile roller bit rotates at the bottom of the pile foundation hole, in addition to the axial pressure of the rotary drill rig drill rod, it is also subjected to the impact load caused by the change in the center height of the cone during rotation, which improves the rock crushing effect.
4. When the inserts of the roller bit roll at the bottom of the pile foundation hole, it crushes the rock alternately. Each working time is short and the wear rate is low, which is conducive to improving the life of the pile roller bit.
