油井水泥膨胀剂研究(Ⅱ)——膨胀机理及影响因素

Study on expandant for oil well cement (Ⅱ): Expanding mechanism.

介绍了抑制水泥浆体收缩的有效方法———使用油井水泥晶体膨胀剂。分析了常见的油井水泥晶体膨胀剂的作用机理和影响因素 ,包括膨胀剂的种类、膨胀源 (硫铝酸盐、方镁石和方钙石 )、塑性体膨胀与硬化体膨胀的关系、膨胀压、使用温度、压力、受限程度、水灰比、化学外加剂等。同时 ,结合膨胀机理提出了使用油井水泥晶体膨胀剂对测井时间和固井质量评价的要求。

The use of expanding agent is considered to be the most effective method to control shrinkage of cement slurries, especially to use crystal expanding additives. The expanding mechanism of popularly used expanding materials and affecting issues were focused on. Various factors influencing expansive properties were discussed in terms of classes, expansive sources( such as sulfoalminate, magnesia and Calcium Oxide), relationship between plastic-paste expansion and set-cement expansion, crystal pressure, curing temperature and pressure, restrain condition, water-to-cement ratio, chemical additives and so on. Further more, the demand for logging time (WOC) and evaluating bonding quality was proposed on the basis of expanding mechanism.