贯通式环喷潜孔锤钻头反循环结构参数研究

Study on reverse circulation structural parameters of through-type ring jet DTH bit

摘要:

反循环钻进技术作为一种先进钻探方法，其在提高钻探效率和减少环境污染方面具有显著优势。进一步优化反循环钻头的结构设计以提升其反循环效果是当前研究的重点。本文聚焦于贯通式环喷潜孔锤钻头反循环结构，通过系统的数值模拟与试验研究，深入探讨其结构参数对反循环效果的影响规律。研究基于EFD技术，采用L₂₇（3¹³）正交试验设计，对11项关键结构参数进行数值模拟分析，明确了各参数对反循环效果的影响权重。结果表明，喷嘴直径、喷嘴与底喷孔接收段入口距离和入口风量是影响反循环效果最为显著的因素。在此基础上，构建了一套高效的环喷式反循环试验器，并通过L₁₈（2×3?）正交试验方案对数值模拟结果进行验证。试验结果表明，当喷嘴直径较小时，内喷孔层数增加可显著提升反循环效果，且入口风量在4~4.5 m3/min区间时，反循环效果最佳。此外，环喷式反循环结构的开放式喷射设计可有效抑制钻头泥包现象，尤其适用于黏土层等易泥包地层的钻进作业。本文的研究不仅为环喷式反循环钻头的设计提供了理论依据和技术支持，同时也为进一步优化钻探工艺参数、提高钻探效率奠定了基础。

Abstract:

Reverse circulation drilling technology， as an advanced drilling method， has attracted significant attention due to its remarkable advantages in improving drilling efficiency and reducing environmental pollution. Further optimizing the structural design of reverse circulation drill bits to enhance their performance remains a key research focus. This study focuses on the reverse circulation structure of the through-type ring jet DTH （Down-the-Hole） bit. Through systematic numerical simulation and experimental research， the influence laws of structural parameters on reverse circulation performance are explored in depth.Based on EFD （Engineering Fluid Dynamics） technology and using an L₂₇（313） orthogonal experimental design， numerical simulations were conducted to analyze the impact of 11 key structural parameters on reverse circulation performance. The results indicate that nozzle diameter， the distance between the nozzle and the inlet of the bottom jet hole， and the inlet air volume are the most significant factors affecting reverse circulation performance. The experimental findings show that a smaller nozzle diameter， an increased number of inner jet layers， and an inlet air volume within the range of 4~4.5m3/min can significantly enhance reverse circulation performance. Moreover， the open-jet design of the ring-jet reverse circulation structure can effectively suppress bit balling， especially in clay layers and other strata prone to bit balling.This study not only provides theoretical and technical support for the design of ring-jet reverse circulation drill bits but also lays the foundation for optimizing drilling process parameters and improving drilling efficiency.