厄瓜多尔A级低渗早强油井水泥浆优化设计

为解决厄瓜多尔A级水泥适应温度、深度范围窄、初始稠度大、可泵性差的难点，开展基于A级水泥的水泥浆配方优化设计研究。通过对A级油井水泥成分分析，水泥密度、细度和比表面积等测试，并开展了其水泥浆稠化性能和抗污染实验，优选出了基于厄瓜多尔低渗、早强和适应范围更广的水泥浆体系。结果表明，A级水泥比表面积为4100～4500 cm³/g,Na₂O含量为0.47%;A级水泥浆体系适用范围可达65℃，10 h的抗压强度均能达到3.5 MPa，渗透率为0.1936 mD，体积收缩率为0.03%。该水泥浆体系在MARIANN-78井技术套管固井施工中进行了应用，CBL/VDL测井结果显示固井质量为优质，显著改善了厄瓜多尔A级油井水泥的性能。

Optimized Design of Class A Low Permeability Early Strength Oil Well Cement Surry

The class a cement used in the Ecuador project has several disadvantages such as narrow temperature and formation depth ranges in which the cement can be used normally, high initial consistency and poor pumpability etc. To solve these problems, study was conducted to optimize the class a cement slurry composition. a new cement slurry was developed as a result of the study. Laboratory experimental results show that the class a cement has specific area of 4100 - 4500 cm2/g and Na₂O content of 0.47%. The upper limit of working temperature of the class a cement slurry is 65 ℃, the 10 h compressive strength of the cement slurry can reach 3.5 MPa, and the set cement has permeability of 0.1936 mD and percent volumetric shrinking of 0.03%. This new cement slurry was used to cement the technical casing of the well Mariann-78. CBL/VDL well logging data show that the quality of the cementing job is excellent; the performance of the class a cement slurry used in the Ecuador project has been significantly improved.