昆2加深井高温固井水泥浆室内研究及应用

Research and application of high temperature cement slurry technology for Kun 2 plus deep well

昆2加深井是柴达木盆地第一口井深超过7 000 m的预探井。固井面临井底温度高、封固段顶底部温差大、环空间隙小、施工压力高、地层承压能力低、水泥浆受钻井液污染严重等难点。针对这些难题,通过优选抗高温性能好、对水泥石强度影响较小的外加剂,经大量实验,优选出了适宜的水泥浆体系,形成了稠化时间可调、滤失量低、稳定性好、强度高的高温水泥浆配方,确保了该井技术尾管和生产尾管的固井质量。该体系在昆2加深井固井的成功应用表明,该体系可解决由于井下高温而引起的固井技术难题。

Kun 2 plus deep well is the first wild cat well with a depth of exceed 7 000 m in Chaidamu basin. This well cementing is faced with difficulties such as high bottom-hole temperature, the long cement column with large temperature difference, small annular clearance, cement slurry seriously contaminated by the drilling fluid, high operation pressure and poor formation pressure. Aiming at these problem, based on optimization of cement additive with good high temperature resistance performance and less impact on the compressive strength. By a series of tests, a high temperature cement slurry system is designed to ensure the cementing quality of intermediate-liner and production liner. The cement slurry has the characteristics of good stability, low fluid loss, good rheology, easy to adjust thickening time and high compressive strength to meet the Kun 2 plus deep well cementing requirements,and it has obtain success in Kun 2 plus deep well’s cement. It solves the problem of high temperature well’s cement.