The wear analysis model and rock-breaking mechanism of a new embedded polycrystalline diamond compact

Abstract

Polycrystalline diamond layer peel-off is a hot topic in oil and gas drilling engineering. When an integrated polycrystalline diamond compact cutter suffers overload, there is a rapid decline in its rock-breaking performance and drilling rate of penetration. To modify the comprehensive performance of polycrystalline diamond compact, we innovatively propose a new embedded polycrystalline diamond compact. According to geometric analysis theory combined with the linear combination rule, the three typical embedded design schemes – the imitation palm-shaped, imitation Z-shaped and ring-embedded designs – are discussed. The influences of the number, size, location and combination of the embedded polycrystalline diamond layer on the polycrystalline diamond compact wear mechanism and rock-breaking performance are analysed. The results show that the embedded element and carbide matrix are combined by brazing welding, which not only exerts high abrasion resistance on the polycrystalline diamond layer but also combines with the good impact performance of carbide matrix. Compared with ordinary polycrystalline diamond compact, the intake amount of a single-embedded polycrystalline diamond compact is smaller, and it wears more evenly during the rock-breaking process. Comparing the results from before and after drilling, it effectively prevents the ordinary polycrystalline diamond compact from easily peeling off when suffering overload. The unique wear analysis model can be applied to other types of polycrystalline diamond compact by adjusting the embedding method. The research conclusions provide useful insights into the study of the polycrystalline diamond compact wear mechanism and rock-breaking performance.