PDC高速切削水泥塞机理研究  

Mechanism of High-Speed Cutting of Cement Plug by PDC Bit

作　　者：辛永安 朱峰 付悦 胡璠 李明慧 蒲晓莉 Xin Yong an;Zhu Feng;Fu Yue;Hu Fan;Li Minghui;Pu Xiaoli(Jianghan Machinery Research Institute Limited Company of CNPC;School of Mechanical Engineering,Yangtze University)

机构地区：[1]中石油江汉机械研究所有限公司 [2]长江大学机械工程学院

出　　处：《石油机械》2024年第7期78-85,共8页China Petroleum Machinery

基　　金：中国石油天然气集团有限公司上游领域关键核心技术重大科技攻关项目“200℃/105 MPa连续管钻磨/射流作业工具研制”(2020B-4018)。

摘　　要：针对连续管在钻井作业时因钻压高、转速低导致钻头磨损严重和钻磨水泥塞效果不佳的问题,基于弹塑性力学和岩石力学,以Drucker-Prager准则作为固井水泥强度准则,通过单轴和三轴试验得到固井水泥弹性模量、泊松比、内黏聚力和内摩擦角等参数,建立固井水泥本构模型,并用ABAQUS软件建立高速切削水泥塞二维有限元模型,在此基础上分析了倾角、切削深度和切削速度对破碎比功的影响。研究结果表明:高速下切削水泥塞产生细小且均匀的碎屑,较低的速度切削水泥塞产生块状或者带状的碎屑;倾角(5°~25°)和切削深度(1.0~2.5 mm)与破碎比功呈正相关,而破碎比功随切削速度的增大而减小,当切削速度为2.26 m/s时破碎比功最小,破碎水泥塞的效率最高。研究结果可为PDC钻头切削水泥塞提供理论支撑。When the coiled tubing is used in drilling,the bit is worn severely due to high weight on bit(WOB)and low rotation speed,resulting in poor milling effect of cement plug.In order to solve this problem,based on elastic-plastic mechanics and rock mechanics,taking the Drucker-Prager criteria as the cement strength criteria,by means of uniaxial and triaxial tests,the parameters of cement such as elastic modulus,Poisson s ratio,internal cohesion and internal friction angle were obtained.The constitutive model of cement was built,and a 2D finite element model of high speed cutting of cement plug was built using ABAQUS software.On this basis,the influences of dip angle,cutting depth and cutting speed on the crushing specific energy were analyzed.The research results show that when the cement plug is cut at high speed,small and uniform debris is produced,while at low speed,massive or banded debris is produced.The dip angle(5°-25°)and cutting depth(1.0-2.5 mm)are positively correlated with the crushing specific energy,while the crushing specific energy decreases with the increase of cutting speed.When the cutting speed is 2.26 m/s,the crushing specific energy is the smallest,and the efficiency of crushing cement plug is the highest.The research results provide a theoretical support for the cutting of cement plug by PDC bit.

关 键 词：PDC钻头 低钻压 高速切削 破碎比功 倾角 切削深度 切削水泥塞 

分 类 号：TE921[石油与天然气工程—石油机械设备]