G306降失水剂在中原油田固井中的应用

中原油田断层多,地下层系复杂,固井作业后在水泥浆候凝期间,地下流体极易侵入,造成水泥环胶结不良甚至窜槽等问题.采用了一种新型的聚合物降失水剂G306.G306油井水泥降失水剂由多种高分子材料、无机盐按一定的比例复配而成,属聚合物微胶粒材料类外加剂.G306具有与其它外加剂配伍性好、稠化时间易调、易泵送,适应温度范围宽,抗高温和降失水性能好的优点,可将水泥浆失水量降至50 mL以下,形成薄膜并具有一定的韧性,利于水泥浆在候凝过程中防止油、气、水窜槽.现场应用表明,G306降失水剂可大大改善水泥浆的综合性能,提高水泥浆的抗气窜、水窜的能力.该水泥浆作业施工顺利,固井质量合格率达99%,优良率达88%,取得了良好的效果.

Application of oil well cement fluid loss agent G306 in Zhongyuan Oilfield cementing operations

Zhongyuan oilfield is a faulted oilfield with complex geological structure. When the cement slurry is bumped down hole and wait on cement, formation fluids easily invade into the cement bond to produce poor cementation, sometimes even results in oil/gas/water channeling. To avoid above problems from happening, a new polymer cement fluid loss agent G306 was developed and applied. Made from several high molecule materials and inorganic salts, G306 works well with other cement additives. It could be used in a wide temperature scale, and the thermal property is stable. When the agent is added in, the slurry is easy to bumped in, the thickening time is adjustable and the fluid loss is in control. The cement slurry filtrate can be reduced the to lower than 50 mL; at the same time, a thin film formed with certain flexibility helps the cement slurry prevent oil/gas/water channeling during setting period. Cementing jobs with this agent in all kinds of wells were all successful, the cementing qualified ratio was 99%, and the excellent ratio reached 88%.