The working principle of the cone is mainly press-in crushing. If the rotation speed is too fast, the sliding will occur without effective crushing, and the alloy teeth will wear quickly.
The rock was crushed by the way of when the roller bits drilling in, the hard rock is crushed, so the speed should not be too high, it need to be crushed little by little.
Do you know what is the reasonable drilling speed for the core barrel with roller bits with different cylinder diameter? Welcome to discuss with us.