镁氧类水泥膨胀剂的作用机理及影响因素

本文介绍一种新型油井水泥膨胀剂———镁氧类膨胀剂的组成、膨胀性能及应用情况。分析了膨胀机理和影响膨胀的因素，包括膨胀剂的煅烧温度、细度，水泥浆的养护温度、养护压力、水灰比、水泥的碱度等。掺有这种膨胀剂的水泥具有防气窜功能，可用于钻井堵漏、修井和固井作业。

MAGNESIA EXPANDANT FOR OILWELL CEMENT AND ITS EXPANSIVE MECHANISM

In this review articled the composition of magnesia cement expandant is presented, the expansive mechanism of magnesia cement is described in terms of the hydation rates of expansion sources in the cement, the motive forces for the cement to expand in volume, and the pore structure of the cement stone formed, and some factors influecing the expansion of magnesia cement are discussed (setting temperature and pressure, particle size of magnesia expandant components, water to cement ratio, and alkalinity of the cement).