硅酸盐钻井液技术在牛斜114井中的应用

胜利油田牛庄洼陷东部主力含油层是沙三段,油藏类型为沉积岩油藏.该地区馆陶组以上地层成岩性差,易造浆;下部地层易坍塌,易漏;底部含有膏泥岩层,需注意防卡、防膏岩水侵.研究了硅酸盐钻井液配方和性能,并对其抑制性、抗固相污染及盐膏污染能力进行了评价.实验证明,硅酸盐钻井液具有良好的抑制泥页岩水化膨胀能力,并具有一定的抗盐膏抗固相污染能力.硅酸盐钻井液体系在牛斜114井进行了现场应用,密度达到了1.50 g/cm3,该钻井液在高pH值环境下能够防止地层的垮塌,起到了保护井壁的作用,悬浮携岩能力强,保护油气层效果好.

Application of silicate drilling fluid in Niuxie114 well

Sha-III member is the main pay(sendimentary rock) of Eastern Niuz huang sag in ShengLi oil field.The formation upside the GuanTao is extra yield and bad diagenesis.While downside formation is hole collapse and lost circulation.The hole bottom contains gypsum/mud rock and thus should avoid sticking and gypsum water invasion.Formulation and properties of silicate drilling fluid was presented and the inhibition,salt resistance and solids tolerance was also evaluated in this paper.It was indicated from tests that silicate drilling fluid had excellent inhibition of hydration expansion of shale and some salt resistance and solids tolerance.The field application in NiuXie114 well indicated that the silicate drilling fluid(1.50 g/cm~3) can avoid formation caving and had strong solids suspension and better formation damage control in high pH surroundings.