GEOLOGICAL AND HYDROGEOLOGICAL JUSTIFICATION FOR THE USE OF WEAR-RESISTANT DIAMOND-BEARING COMPOSITES IN WELL DRILLING

Abstract

The relationship between the geological and hydrogeological conditions of drilling and the material requirements for core drilling tools is considered. Particular attention is paid to the influence of the physical and mechanical properties of rocks, their abrasiveness, fracturing, heterogeneity, and water saturation on the nature of matrix wear and the stability of diamond-bearing cutters. Based on experimental data for Fe–Cr–Cu–Ni–Sn matrices with ZrO₂ addition formed by spark plasma sintering, the changes in relative density, compressive and bending strength, microhardness, and fracture toughness were analyzed. It is shown that increasing the ZrO₂ content up to 10% is accompanied by a growth in the set of mechanical characteristics, which has practical significance when drilling through hard and abrasive rocks, including the construction of exploration and hydrogeological wells.

The established patterns make it possible to justify the choice of composition and operational characteristics of the matrix material, taking into account specific geological and technical drilling conditions. Increased strength and microhardness contribute to resistance to abrasive wear, while an increase in fracture toughness reduces the probability of local matrix failure under dynamic and alternating loads. This is especially important when drilling heterogeneous rocks alternating in strength and abrasiveness, where the drilling tool is subjected to complex mechanical and hydrodynamic impacts.

An engineering-geological interpretation of the obtained results is formulated: the matrix resistance to abrasive, impact-cyclic, and contact impacts contributes to maintaining the performance of diamond-bearing cutters in a heterogeneous profile. The obtained results create a scientific and practical basis for the targeted selection of the matrix composition of diamond drilling tools, increasing its wear resistance, preserving the geometric parameters of the working part, and extending the service life when drilling exploration and hydrogeological wells.