首页|冲旋步进钻井提速方法的井底裂纹拓展特性

冲旋步进钻井提速方法的井底裂纹拓展特性

扫码查看
原文链接
  • NETL
  • NSTL
  • 万方数据
针对深部地层井底岩石硬度高、强度大和应力集中现象导致的岩石可钻性差、破岩效率低和使用寿命短的问题,提出旋冲钻井和差压步进破岩方法相结合的冲旋步进钻井提速新理念.为了研究冲击作用下差压步进钻头破碎地层岩石的裂纹拓展规律,采用有限-离散元(FDEM)方法建立了球齿冲击三维薄板模型,开展了球齿在不同冲击能量、冲击位置及岩石种类等条件下的冲击破岩过程模拟,获得了阶梯型井底岩石在冲击作用下的裂纹扩展规律.研究结果表明:由于阶梯面的存在,球齿在冲击作用下对阶梯型井底造成的预损伤区域比常规井底更大,冲击位置靠近阶梯面的裂纹扩展效果更好;双球齿冲击阶梯井底容易形成较大范围的岩石破碎区,降低了破碎阶梯井底地层岩石的难度;球齿冲击过程中对青砂岩造成的预损伤区域比花岗岩大,在冲击能量相同的情况下球齿冲击破碎花岗岩更为困难.利用冲旋步进钻井方法理论上可以进一步提高难钻地层钻井速度,但具体效果需要经现场试验及优化.所得结论可为深部难钻地层钻井速度的提升提供新的思路.
Propagation Characteristics of Bottomhole Cracks Created by the Percussive-Rotary Stepping Drilling ROP Improving Method
In order to solve the problems of poor rock drillability,low rock-breaking efficiency and short serv-ice life caused by high hardness,high strength and stress concentration of bottomhole rock in deep formations,a new concept of ROP improvement by percussive-rotary stepping drilling combining percussive-rotary drilling and dif-ferential pressure stepping rock-breaking method was proposed.In order to study the crack propagation law in for-mation rocks broken by differential pressure stepping bit under impact,an spherical button impact 3D sheet model was built using the finite-discrete element method(FDEM).The percussive rock-breaking process of the spherical button under conditions such as different impact energies,impact positions and rock types was simulated,obtai-ning the crack propagation law of stepped bottomhole rocks under impact.The research results show that due to the presence of stepped face,the predamage area caused by spherical button under impact in the stepped bottom hole is larger than that in the conventional bottom hole,and the crack propagation effect is better when the impact posi-tion is close to the stepped face.The double spherical button impact at stepped bottom hole is prone to forming a relatively extensive rock-breaking area,reducing the difficulty of crushing the formation rocks at stepped bottom hole.The predamage area caused by spherical button impact in blue sandstone is larger than that in granite,and under the same impact energy,the crushing of granite by spherical button impact is more difficult.The percussive-rotary stepping drilling method can theoretically further improve the drilling speed in bad ground,but the specific effect needs to be tested and optimized on site.The research conclusions provide new ideas for improving drilling speed in deep bad ground.

percussive-rotary stepping drilling methodstepped bottom holedifferential pressure stepping bitfinite-discrete element coupling(FDEM)crack propagation

刘永旺、刘嘉雄、管志川、王华健、赵国山、张曙辉

展开 >

深层油气全国重点实验室(中国石油大学(华东))

中国石油大学(华东)石油工程学院

中石化经纬有限公司胜利定向井公司

西南石油大学油气藏地质及开发工程国家重点实验室

展开 >

冲旋步进钻井方法 阶梯井底 差压步进钻头 有限-离散元耦合 裂纹扩展

国家重点研发计划政府间国际科技创新合作重点专项中国石油天然气集团有限公司重大科技项目国家自然科学基金面上项目

2021YFE0111400ZD2019-183-00552074324

2024

10.16082/j.cnki.issn.1001-4578.2024.07.006

石油机械
中国石油天然气集团公司装备制造分公司 中国石油学会石油工程专业委员会 江汉机械研究所 江汉石油管理局

石油机械

CSTPCD北大核心
影响因子：0.737
ISSN：1001-4578
年,卷(期)：2024.52(7)