Anti-balling Mechanism on the Non-smooth Surface of Bionic Polycrystalline diamond compact Drill Bits

Abstract

Polycrystalline diamond compact (PDC) bit balling is one of the major factors that limits the penetration rate of drilling and causes bit failure in soft stratum. In order to solve the PDC bit balling problem, in this research we designs typical bionic non-smooth surfaces and analyzes the anti-adhesion mechanisms. Next, the non-smoothness characterization is extended from a two-dimensional to three-dimensional in which the area ratio and the width ratio are used to characterize lateral and longitudinal non-smoothness. Then, a comparative experiment between typical non-smooth surfaces and the smooth surface condition is carried out. The results show that the scale-like non-smooth surface has the best anti-adhesion effect and that longitudinal non-smoothness has a greater influence on mud block adhesion than lateral non-smoothness. The research results also show that after applying the principle of anti-adhesion and resistance reduction for the non-smooth surface of soil animals to the design of the flow channel of a PDC drill bit, the novel bionic anti-balling PDC bit can effectively avoid the problem of bit balling.