温度及外加剂对水泥浆流变性的影响

Affects of temperature and additives on rheology of cement slurry

水泥浆流变性与水灰比、水泥颗粒的粒度和形状、水泥化学组分及颗粒表面上组分的相对分布、外加剂种类和加量、试验条件(温度和压力)等众多因素密切相关,因此对特定浆体流变模式及流变规律的确定结果,往往因研究者及实验条件不同而存在差别。以嘉华G级油井水泥为研究对象,以流变学基本原理为基础,以高温高压流变仪获得的流变测试曲线为依据,采用赫切尔-巴尔克莱模式本构关系确立了在不同井温下水泥浆体流变模型,探讨了温度、外加剂等对流变性能的影响规律及其本质,为深井水泥浆体系设计及流交学计算提供了基础。计算及分析结果表明,建立的流变模式及确定的流变参数值具有良好的精度。

Cement slurry rheological properties are related with multitude factors as w/c, grain grade and shape of cement particle, chemical composition and its relative distributing in cement particle surface, sort and dosage of additives, experiment conditions (temperature and pressure), etc. . Therefore, to determine the rheological mode and law of certain slurry often leads to different conclusion because of the difference of researchers and experiment restrictions. However, cement slurry rheological model for different well temperatures has been established based on Herschel-Bulkely rheological model as constitutive equation, Jiahua Class G oilwell cement as subject, rheology as fundamental principle and rheological curve tested by HTHP Rheological equipment as foundation. Influence law of temperature and additives on rheology of cement slurry and its nature are analyzed, and the foundation of cement slurry design and rheological calculation for deep-well cementing are provided. Calculating and analyzing have shown that the rheological model and the rheological parameters determined by the model have good accuracy.