宽刃齿微钻头设计及破岩机理研究  

Design and Rock-Breaking Mechanism of Micro-Bit with Wide Edge Cutter

作　　者：胡莉 况雨春 龙伟 林伟 韩一维[2] Hu Li;Kuang Yuchun;Long Wei;Lin Wei;Han Yiwei(Chengdu Jincheng College;School of Mechanical Engineering,Southwest Petroleum University)

机构地区：[1]成都锦城学院,四川省成都市611731 [2]西南石油大学机电工程学院

出　　处：《石油机械》2024年第11期1-11,共11页China Petroleum Machinery

基　　金：四川省区域创新合作项目“高性能复合钻头关键技术研究及新产品开发”(2021YFQ0041)。

摘　　要：常规PDC钻头在钻进塑性地层时,存在吃入困难、机械钻速低等现象。为增强钻头吃入岩石的能力,提出一种新型PDC钻头——宽刃齿钻头。基于侧向力平衡布齿理论,完成微钻头的结构设计;基于有限元软件,建立宽刃齿微钻头和常规齿微钻头破岩分析模型,并开展了微钻头水平井试验研究,结合数值模拟结果探究宽刃齿钻头的破岩机理。研究结果表明:在相同工况下,宽刃齿钻头相比于常规齿钻头吃入岩石能力更好,破岩效率更高;同时,增加转速和布齿密度,钻头端的黏滑振动现象明显减弱;增加钻速导致钻压增加,钻头端黏滑振动现象加剧;在不同岩石种类的试验中,与砂岩相比,灰岩在同等条件下破碎时所需的钻压和扭矩更大,更难被破碎。研究结果可为深部难钻地层,尤其是塑性地层中的钻井提速问题提供新思路。Improving the rate of penetration(ROP)has always been a hot topic in oil production studies.In recent years,the focus of exploration and development has gradually shifted towards deep and ultra-deep layers.As the production depth increases,the confining pressure and rock plasticity also increase,leading to increased drilling difficulty and decreased efficiency.Conventional PDC bits encounter difficult penetration and low ROP when drilling in plastic formations.In order to improve the ability of the bit to penetrate rocks,a new type of PDC bit with wide edge cutter was proposed.First,based on the lateral force equilibrium cutter arrangement theory,the structural design of the micro-bit was completed.Second,the finite element software was used to build the rock-breaking analysis model of micro-bit with wide edge cutter and conventional cutter,and experimental study on micro-bit in drilling horizontal wells was carried out.Finally,combined with numerical simulation results,the rock-breaking mechanism of bit with wide edge cutter was investigated.The results show that under the same working conditions,the bit with wide edge cutter has better rock penetration ability and higher rock-breaking efficiency than conventional PDC bit.Increasing the rotation speed and cutter arrangement density significantly reduces the stick-slip vibration phenomenon at the bit end.Increasing ROP leads to an increase in weight on bit(WOB)and an enhancement of stick-slip vibration at bit end.In experiments on different rock types,compared with sandstone,limestone needs to be broken by greater WOB and torque under the same conditions,suggesting that limestone is more difficult to break.The research results provide new ideas for improving the ROP in deep hard-to-drill strata,especially plastic formations.

关 键 词：钻井提速 PDC钻头 宽刃齿 破岩机理 数值模拟 黏滑振动 

分 类 号：TE242[石油与天然气工程—油气井工程]