辽河油田油页岩地层全油基钻井液技术

沈平1井是辽河油田第1口油页岩和泥质白云岩互层为目的层的预探水平井。由于油页岩地层的特殊性,井壁失稳现象突出,油层段轨迹控制难,安全环保工作敏感,钻井时效难以提高。在处理剂研发的基础上形成了适用于沈平1井的抗温达150℃、密度为1.55 g/cm3的全油基钻井液体系。现场应用结果表明:该套全油基钻井液体系综合性能优良,具有良好的流变性、抑制性、封堵性、抗污染性、润滑性及高温稳定性,能够控制油页岩水化膨胀,解决井壁失稳的难题。与同类型井相比,沈平1井机械钻速提高1.6倍,生产时效提高30%。

Whole Oil Base Drilling Fluid Technology for Oil Shale Drilling in Liaohe Oilfield

Well Shenping-1 is the first horizontal exploration well having oil shale and argillaceous dolomiteinterbeds reservoirs. The existence of oil shale presents drilling difficulties such as borehole instability, well path control difficult in reservoir drilling, environmental issue and low ROP, to name but a few. A whole oil base drilling fluid was developed for use on Well Shenping-1. It has a density of 1.55 g/cm3 and temperature resistance to 150 ℃. As a whole oil mud, it has good rheology, inhibitive capacity, plugging capacity, contamination resistance, lubricity and high temperature stability, thus is able to control the swelling and sloughing of the oil shale when in contact with water. Shenping-1 had an average ROP 1.6 times that of the wells drilled nearby, and time efficiency of drilling was increased by 30%.