元深1井超深井钻井提速关键技术

Key Drilling Technologies for Increasing ROP in Ultra-Deep Well Yuanshen 1

元深1井是部署在川北低缓构造带上的重点探井,钻井过程中面临地层压力体系复杂、井眼易坍塌、钻井液易漏失、陆相地层研磨性强、井控风险高等技术难题。根据地质特征,借鉴邻井钻井经验,应用泡沫钻井技术,提高浅部地层大尺寸井眼机械钻速;应用“涡轮钻具+孕镶金刚石钻头”和“旋冲钻具+混合式钻头”提速技术,解决陆相高研磨性地层机械钻速低的难题;应用耐高温防漏堵漏钻井液,配套“高效PDC钻头+大扭矩螺杆”提速技术,实现海相多压力体系复杂地层安全快速钻进;用微心PDC钻头钻进目的层,在满足岩屑录井需要的同时,提高了钻井效率。该井顺利钻至井深8866.00 m完钻,创中国石化四川盆地直井井深最深纪录,为四川盆地超深井钻井积累了经验。

Well Yuanshen 1 is a key exploration well located in the gentle structural belt of northern Sichuan.The drilling process encountered several technical challenges,including complex formation pressure systems,borehole collapse,drilling fluid loss,strong terrestrial formation abrasiveness,and high risk of well control,etc.Based on the geological characteristics and drilling experiences of adjacent wells,a series of drilling technologies were implemented to increase the rate of penetration(ROP).Foam drilling technology was utilized to improve the ROP in large boreholes within shallow formations.For the highly abrasive terrestrial formations,the technologies of“turbodrill+impregnated diamond bit”and“rotary percussion drilling rig+hybrid drilling bit”were employed to enhance ROP.The combination of high-temperature,leak-proof drilling fluid with“high-efficiency polycrystalline diamond compact(PDC)bit+high torque screw”technology enabled safe and rapid drilling in the complex formations of the marine multi-pressure system.The microcore PDC bit was used to drill into the target zone,enhancing drilling efficiency while meeting the needs of cuttings logging.The well was successfully drilled to a depth of 8866.00 meters,setting a Sinopec’s record for the deepest vertical well in the Sichuan Basin.This achievement provided technical experience for ultra-deep well drilling in the Sichuan Basin.