聚胺仿油基钻井液在高位垂比水平井的应用

Application of Polyamine Imitation Oil-based Drilling Fluid in High Ratio of Displacement and Vertical Depth Horizontal Wells

川西地区白恶系、侏罗系泥岩、砂岩互层频繁,极易水化膨胀、分散,前期施工的水平井表现出较多复杂情况:井壁易失稳,摩擦阻力大,易发生托压、卡钻等问题。室内针对以上技术难点,结合新型抑制剂聚胺和仿油基处理剂的优点,研制出了一套具有强抑制、强封堵和优良润滑性能的聚胺仿油基钻井液。该钻井液泥页岩水化膨胀率小于10%,滚动回收率达98%以上,润滑系数小于0.1,大幅减少了液体润滑剂的使用,降低了地层水污染的机率。该技术成功应用于川西地区30余口高位垂比水平井,各试验井井壁稳定,平均摩擦阻力小于12t,平均机械钻速较前期施工井提高34.31%,解决了中浅层井壁失稳、井下托压等技术难题。现场试验表明,聚胺仿油基钻井液技术具有广阔的应用前景。

In west Sichuan,interbed of mudstone and sandstone in Cretaceous and Jurassic is easy to hydrate,expand,and disperse in mud,which causes borehole instability,high friction,back pressure and pipe-stuck.In this paper,a polyamine imitation oil-based drilling fluid system is developed that is combined with the advantages of the polyamine and imitation oil-based treating agent.The evaluation results show that the hydrated mudstone expansion rate is less than 10%,the rolling recycling rate is more than 98%,and the lubrication coefficient is less than 0.1.The applications of over 30 high ratio displacement and vertical depth horizontal wells are successful that the wellbore is stability,the average friction is less than 12 t,and the average ROP is increased by 34.31%.