DG抗高温隔离液在古深1井的应用

Application of DG High Temperature Resistant Spacer in Well Gushen-1

古深1井是大庆油田在古龙地区的一口风险探井,设计井深5 500 m,实际完钻井深为4 739 m。钻进过程中,多次出现塌、漏、卡等事故,造成井径不规则。为平衡压力,压稳地层,更好地隔离钻井液和水泥浆,提高顶替效率,设计采用DG抗高温隔离液。DG抗高温隔离液抗高温可达150℃,密度调节范围宽,抗高温悬浮稳定性好,失水量少,与水泥浆和钻井液相容性好。古深1井采用双级注水泥工艺,固井施工过程十分顺利,隔离液密度均匀,泵送容易,无发泡现象。从声幅测井情况来看,水泥面上部与隔离液交界处界面清楚,水泥环胶结良好,水泥返高达到了设计要求,混浆过渡段短,固井质量合格。

Well Gushen-1 is a risk exploration well in Gulong area of Daqing Oilfield,with a designed depth of 5500m and completed depth of 4739m.Several accidents were occurred during drilling,including wellbore collapse,circulation lost,pipe sticking,and irregular wellbore.For the purpose of balancing pressure and stabilizing formation,better isolating drilling fluid and slurry,improving replacing ratio,the DG high temperature resistant spacer was developed and used.It can used in temperature up to 150℃,and has better density adjusting range,better suspension,less water loss,better adaptability with drilling fluids and slurry.Two-stage cementing slurry injecting technique was used in Well Gusheng-1.Cementing operation was carried out smoothly.The density of spacer fluid was well-distributed;it was delivered easily and there was no foaming.The acoustic amplitude log indicates that the interface of spacer fluid and top cement was clear; the cementation of cement sheath was well;the return height met the designed requirements;the length of mixtinite of spacer fluid and cementing slurry was short.The cementing quality of Well Gushen-1 was qualified.