Domed type PDC bits front teeth are non-planar cutters, the back teeth are conical teeth, the front row tooth composite plate adopts convex ridge structure design, which can effectively improve the impact resistance and wear resistance of the bit. Rear row compound conical teeth are conical cutting elements, which can effectively share the drilling load of the front row main cutters by participating in formation fragmentation, which is conducive to protecting the front row cutters and greatly improving the service life of the bit.
When the PDC bit works, first the raised edges of the front non-planar composite touch the formation and pre-break the rock. Then the composite plane is partially ploughed to compound break the formation rock. This design increases the resistance ability of the diamond composite and transforms the main cutting force from a curved plane to a large angle cutting, which requires a lower cutting force.
Due to thicker diamond layer and proprietary diamond particle distribution and mixing technology, it also obtains better frontal impact resistance, compared with conventional PDC composite, it has stronger rock breaking ability and better wear resistance. At the same time, the rear-row conical teeth exert higher point load on the formation than the conventional flat PDC composite plates, so the formation with high compressive strength can be broken more effectively by the combined mechanism of plough scraping and shearing. As the force fed into the formation passes through its axis, it has a more balanced lateral force, which effectively reduces the lateral and longitudinal vibration of the bit and prolongs the bit life.
