煤矿井下定向钻进用新型PDC钻头

Research on new type of directional drilling PDC bit used in coal mine drill

在硬地层或软硬交错地层中定向钻进时,常规单齿式平底钻头磨损较为严重。为此,我们开发出一种新型定向PDC钻头,并采用数值模拟方法分析该钻头的破岩机理和受力特性。结果表明:与普通平底钻头相比,在同等工况条件下,新型定向PDC钻头的破岩载荷比普通平底钻头降低36%,破岩效率提高近50%。根据模拟结果,试制新型定向PDC钻头并进行现场试验。试验显示:在中硬至硬地层中进行定向钻进施工时,与普通平底钻头相比,新型定向PDC钻头平均寿命提高2倍以上,进尺效率提高约1倍,降低钻进成本。

When drilling hard formation or staggered formation,normal single layer flat base bit wears heavily.Therefore,we developed a new kind of directional drilling polycrystalline diamond composite（ PDC） bit and analyzed its rock breaking mechanism and stress property by using numerical simulation method. Results show that rock breaking load of the new bit decreases by 36% and breaking efficiency increases by 50% compared with normal bits at the same working condition. Field tests were implemented with the new kind of bits. It turns out that when drilling hard formation or staggered formation,the life of new bits is 3 times as much as that of normal bits,and that the drilling efficiency almost doubles. New kind of PDC bit could decrease the drilling cost.