韧性防气窜水泥浆体系在水平井中的研究与应用

Study and application of ductile anti-gas channelingcement slurry system in horizontal wells

水平井固井存在套管居中度低,二界面封固质量差,容易窜槽,顶替效率差,体积压裂要求水泥石具有高强的弹韧性及耐久性等难题。为保证水平井固井质量,针对以上技术难题,研究开发了一套适用于水平井固井的韧性防气窜水泥浆体系,该水泥浆体系沉降稳定性上下密度差≤0.006 g/cm^(3),防窜系数SPN<3,7 d弹性模量≤6.5 GPa。该体系在吐哈油田应用20余井次,为水平井安全高效开发提供了技术支撑。

There are some problems in horizontal well cementing,such as low casing,poor sealing quality,easy channeling,poor displacement efficiency,and high strength,toughness and durability of cement paste required by volume fracturing.In order to ensure the cementing quality of horizontal well,in view of the above technical difficulties,we have developed a set of ductile anti-gas channeling cement slurry system which is suitable for horizontal well cementing.The density difference of settlement stability of the slurry system is≤0.006 g/cm^(3),channeling prevention coefficient SPN<3,7 d elastic modulus≤6.5 GPa.The system has been applied to more than 20 wells in Tuha oilfield,providing technical support for safe and efficient development of horizontal wells.