Polycrystalline diamond compact for plastic stratum

Abstract

The invention discloses a polycrystalline diamond compact for a plastic stratum. The polycrystalline diamond compact comprises a polycrystalline diamond layer and a hard alloy matrix, wherein the rearend of the polycrystalline diamond layer is connected with the front end of the hard alloy matrix; an inner cavity which is concave inwards is formed in the middle of the end surface of the front endof the polycrystalline diamond layer; a boss which is convex forwards is arranged in the middle of the inner cavity; and a plurality of cutting high points which are convex forwards are arranged on the top of an annular cavity wall of the inner cavity. The inner cavity, the boss and the cutting high points which are used as the tops of cutting edges are arranged on the end surface of the front end of the polycrystalline diamond layer, the capability of the polycrystalline diamond compact for entering the stratum can be improved, plastic rock debris is easy to break, and the chip breaking anddischarging capability of the plastic stratum is improved. The polycrystalline diamond compact for the plastic stratum is particularly suitable for drilling of the plastic stratum and is also suitablefor drilling of a stratum of which the performance is close to that of the plastic stratum.

Description

technical field [0001] The invention relates to a polycrystalline diamond composite sheet for a PDC drill bit used in oil and gas drilling, geological exploration, engineering excavation, prospecting drilling, etc., in particular to a polycrystalline diamond composite sheet for plastic formations. Background technique [0002] Polycrystalline diamond compacts take into account the comprehensive properties of high hardness and wear resistance of diamond and high impact resistance of cemented carbide, and are considered to be ideal drilling materials. From around the 1980s, countries have gradually adopted polycrystalline diamond compacts as the main cutting elements in drilling for oil and natural gas. At present, polycrystalline diamond compacts have been widely used in PDC drill bits as super wear-resistant cutting elements, and are widely used in oil and natural gas drilling and other fields. [0003] With the wide application of polycrystalline diamond compacts, its appl...

AI Technical Summary

Problems solved by technology

The polycrystalline diamond compact at the front of the traditional PDC bit still suffers from inefficiency when drilling into specific formations

[0004] When drilling into highly plastic formations, because the traditional polycrystalline diamond composite sheet adopts a planar tooth structure, it is difficult to penetrate into the formation for drilling, resulting in a reduction in the aggressiveness of the drilling tool; at the same time, the traditional polycrystalline diamond compact In the stratum, the chip-breaking ability is insufficient, resulting in a large accumulation of cuttings. The accumulation of cuttings causes repeated cutting of cuttings, which reduces the cutting efficiency and increases the additional wear of the composite sheet; at the same time, the accumulation of cuttings also causes cutting Increased resistance, resulting in overheating damage to the polycrystalline diamond compact

In summary, the current traditional polycrystalline diamond compacts are relatively weak when drilling into highly plastic formations, and often appear difficult to drill, poor chip breaking ability, low efficiency and premature damage to the compacts

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