深井水泥石低温下强度增长剂的应用

针对中原油田油气层埋藏深、油气分散、地温梯度高、深井井底温度高、封固段长、水泥浆低温下不易凝固、水泥石强度发展慢等问题,研制出了一种水泥石增强剂G606.这种外加剂加入水泥浆后对流动度影响不大,降低了水泥浆失水量,对稠化时间有一定的影响,特别是低温下稠化时间大大缩短.现场应用表明,采用增强剂G606配制的水泥浆性能稳定,可调性强;稠化曲线呈直角,有利于阻止油气水窜槽,低温下水泥石强度发展快,克服了低温下水泥浆长期不凝固的难题,完全可以满足正常测井和井下作业需求.加入增强剂G606的水泥浆在36口深井中固井,固井施工顺利,固井合格率为100%,优良率为89%.

Application of q strength enhancer for deep well cement slurry at low temperature

There are several problems existing in Zhongyuan oilfield, e.g., reservoir is deep and sporadic; geothermal gradient and well bottom temperature are high; cementing interval is long; cement slurry does not easily consolidates at low temperature and cement stone strength develops slowly, etc.. To cope with the problems, a cemet strength enhancer named G606 was developed. The enhancer produces a little influence on cement slurry flowability, reduces filtrate loss of slurry and can short cement slurry's thickening time specially at low temperature. The property of the slurry prepared with the enhancer has short thickening time, displays the right angle curve and cement strength develops quickly at low temperature. It can fully satisfies the requirements of normal logging time and downhole jobs.The enhancer was used in 36 deep wells, and the cementing operation was successful with the cementing qualified rate of 100% and excellent rate of 89%.