成膜封堵钻井液在旅大10-1油田的应用

The Application of a Filming Sealing Drilling Fluid in Block Lvda10-1

A31和A32井是旅大10-1油田的2口定向井,目的层均为东营组。该油田东营组泥岩易垮塌,储层物性为高孔高渗,地层压力亏空情况不落实,易发生漏、塌、缩、卡等复杂情况。为了最大程度地保护油气层,在A31、A32及A31侧钻井的油层段应用了成膜封堵钻井液(CBF)。CBF钻井液的主要添加剂为复配材料ZJ-VIS,其为由成膜剂、抑制剂、聚合物增黏剂和油溶性暂堵剂特殊粒子组成的胶体,对该钻井液性能进行了室内实验评价。现场应用结果表明,CBF钻井液的封堵、抑制性好,起下钻未遇阻卡,套管顺利下到井底;防塌性好,A31s井三开井眼最大扩大率为3%,无井壁掉块返出;润滑性好,在泥岩地层滑动调整轨迹时平均机械钻速达10m/h,且摩阻很小;油层保护性能好,2口井的产量均比较理想;满足了旅大10-1油田调整井的钻井要求。

Wells A31 and A32 are two deviated wells located in Block Lvda10-1,targeted at the sloughing Dongying formation having a high porosity and high permeability.Mud losses,borehole sloughing,tight hole and pipe sticking were encountered during drilling.To avoid formation damage,a filming sealing drilling fluid(CBF)was used in two adjustment wells and the sidetrack section of well A31.Field operation showed that the percent hole enlargement of well A31 was only 3% at most.No cave-in was encountered.Hole lubricity was improved through the use of some special additives.The average ROP in the clay stone formations was as high as 10 m/h.Production rates of the two wells were both satisfactory.