深部开窗侧钻井元坝1–侧1井固井技术

元坝1–侧1井是在元坝1井的基础上进行开窗侧钻的一口重点探井，目的是为了进一步揭示元坝地区礁滩相储层气藏情况。完钻斜深7427.23 m，?146.1 mm无接箍尾管下深7425.81 m，是目前川东北地区完钻和套管下深最深的一口井。具有井深、温度高、压力高、钻井液密度高、环空间隙小、井斜、位移大、裸眼段长、小间隙、无接箍套管不能加装扶正器、套管在井眼中居中困难、地层破裂压力梯度不详、面临井漏等技术难题。通过采取优选抗高温水泥浆体系、加重隔离液体系，合理设计入井管柱结构，采用平衡压力固井技术，改进配浆方式等一系列技术措施固井。保证了套管顺利下入，解决了井漏、顶替效率低、施工泵压高、气体窜槽等问题。固井施工顺利，测井解释固井质量优，为超深井、小间隙井固井提供了可借鉴的依据。

Cementing technology for Yuanba No.1-sidel deep side tracking well

Yuanba No.1-side1 well is an important a side-tracking exploration well based on Yuanba No.1, which is disposed to reveal the situation of reef beach phase pay zone gas reservoirs in Yuanba area. It is currently the deepest well with the final inclined depth 7427.23 m and the run in hole (RIH) depth of the flush liner ?146.1 mm 7425.81 m in southeastern Sichuan. It features in high temperature and pressure, high drilling fluid density, small annular clearance, inclined well bore, great offset, long open hole, and small clearance. In addition, a lot of technical problems need to be solved. For instance, centralizers can not be added to the flush casing, to keep casing centralized inside the well bore gets difficult, and circulation loss is likely to occur. Systematic cementing methods are adopted, such as the optimization of high temperature resistance cementing slurry system and weighted spacer fluid system, the rational design of RIH string combination, the use of balanced pressure cementing techniques, and the improvement of slurry making method. All the methods ensure the casing is run in hole successfully, solving the problems like circulation loss, poor displacement, high pump pressure, and gas channeling. Cementing operation runs successfully, and logging interpretation shows the cementing quality is excellent. The successful well cementing creates the record of ultra deep well cementing in southeastern Sichuan, providing useful reference for cementing of ultra deep wells and wells of small clearance in the future.