水泥膨胀剂SEP - 1 在长封固段固井中的应用

The Application and Development of Expansion Agent SEP-1 in Long Cementing Section

曹庆和,王爱宽,田相元,徐　林

Cao Qinghe, Wang Aikuan, Tian Xiangyuan, et al

中原油田分公司工程监督中心

Engineering Supervision Center , Zhongyuan Oilfield Company , SINOPEC, Henan 457001 , P. R. China

为解决吐哈油田长封固段固井质量问题,研制了SNC(减轻剂) + SEP - 1 (膨胀剂) 低密度、高强度油井水泥。经现场7 口井试验,未发生井漏、憋泵、低返等问题,质量全优,大大提高了固井质量。SNC 可防漏、防塌和保护油气层; SEP - 1 可大大降低析水,补偿水泥凝固时的体积收缩,增加水泥石强度30 %～50 %。2 种外加剂联合使用,可配成低密度、高强度水泥浆。由于加大了水灰比,一方面加大了水泥浆的紊流程度,提高了顶替效率;另一方面减少了水泥用量,降低了固井成本。SEP - 1 单独使用,可配成高密度水泥浆。

Tuha Oilfield has developed SNC ( lightening admixture) + SEP-1 ( expansion agent ) low density and high strength cement in long cementing section. The cement job quality was greatly improved without lost circulation and building pressure and low return in 7 wells. It has been proved that SNC could prevent from lostciculation and collapse and protect the hydrocarbon zone. SEP-1 could help reducing fluid loss and compensating the volume shrinkage of the cement while it concreting , and increasing cement strength by 30 % ～ 50 %. The combination of the two additives could contribute to the low-density and high-strength cement milk. High water-cement ration increased the turbulent extent and improved the mud displacement efficiency and reduced the cement quantity. The single use of SEP-1 could produce high-density cement milk.