摘要
文章以四川盆地蓬莱气区沙溪庙底、自流井组、须家河组地层为例,开展了原位温度、压力下的抗压强度和可钻性研究。探索了原位参数对岩石特性的影响规律:原位条件下,地层强度呈非线性增长,岩石塑性增强,切削过程由体积破岩转化为研磨性破岩;揭示了原位可钻性变化规律:沙溪庙底、自流井组和须家河组在地表和原位条件下的可钻性级值分别为5~6、7~8、6~7,原位条件下上述地层平均钻速分别降低50.6%、61.2%和43.8%,破岩效率显著降低。基于离散元法建立了原位温度压力下的自流井组地层-异形齿互作用模型并开展了破岩模拟研究,获得了针对自流井组的最佳切削齿齿形和钻头结构参数,即最佳齿形三棱齿、后倾角20°、齿径16 mm。基于理论研究成果研发的PDC钻头在四川盆地蓬深X井自流井组地层开展现场试验,平均机械钻速同比邻井提高27.2%。现场试验表明文章研究成果能够有效指导蓬莱气区自流井组地层钻头设计。
In this paper,taking the formations of Shaximiao bottom,Ziliujing,and Xujiahe Formation in Penglai gas area of Sichuan Basin as examples,the compressive strength and drillability under in-situ temperature and pressure are studied.The influence of in-situ parameters on rock properties is clarified:under in-situ conditions,the formation strength increases nonlinearly,the rock plasticity increases,and the cutting process changes from volumetric rock breaking to grinding rock.The variation of in-situ drillability is revealed:the drillability of Shaximiao bottom formation,Ziliujing formation,and Xujiahe formation under atmospheric environment and in-situ conditions are 5-6,7-8,6-7 respectively.Under in-situ conditions,the average ROP of the above formations are reduced by 50.6%,61.2%and 43.8%respectively,and the rock breaking efficiency is significantly reduced.Based on the discrete element method,the formation-special-shaped cutter interaction model under in-situ temperature and pressure was established and the rock breaking simulation study was carried out.The optimal cutter and drill bit structure parameters were obtained,that is,the optimal cutter is triangular cutter,the back rake angle is 20°,and the diameter is 16 mm.The PDC bit developed based on the research results was tested in the Shaximiao to Zhiliujing formation of well X in the Pengshen block of Sichuan Basin.The average ROP was 27.2%higher than that of adjacent wells.Field experiments show that the research results of this paper can effectively guide the design of efficient PDC bit in Penglai gas area.
作者
刘彬
姚建林
喻可彬
LIU Bin;YAO Jianlin;YU Kebin(Drilling&Production Technology Research Institute,CNPC Chuanqing Drilling Engineering Co.,Ltd.,Guanghan,Sichuan 618300,China;Petroleum Drilling&Production Technology Co.,Ltd.,CNPC Chuanqing Drilling Engineering Co.,Ltd.,Guanghan,Sichuan 618300,China;Xinjiang Branch,CNPC Chuanqing Drilling Engineering Co.,Ltd.,Korla,Xinjiang 841000,China)
出处
《钻采工艺》
CAS
北大核心
2023年第4期38-44,共7页
Drilling & Production Technology
关键词
蓬莱气区
原位条件
岩石力学试验
可钻性试验
离散元破岩模拟
Penglai gas area
in-situ conditions
rock mechanics experiment
drillability experiment
rockbreaking simulation by discrete element method
