一种新型注水泥前置隔离液

由于目前使用的隔离液不可固化,使得套管壁—水泥环—井壁的界面存在不可固化层,容易形成微间隙和微环空,严重影响界面胶结质量.针对该问题研制了一种既可隔离又可实现自身固化的注水泥前置隔离液体系.该隔离液密度在1.3～2.4g/cm3范围内可调,流变性能可调,流动度可控制在19～23cm之间,在50～90℃下,固化效果良好,24h抗压强度可达8MPa以上,稠化时间可调；同时该隔离液与钻井液、水泥浆的相客性好,并可实现与钻井液和水泥浆的整体固化胶结,3者整体固化强度在48h下达到8MPa以上,使得套管壁—水泥环—井壁的界面能够很好地固结在一起,提高了界面胶结质量.该隔离液突破了传统隔离液不能固化的特点,淡化了顶替机理和顶替效率,提高了固井作业安全和封固效果,具有广阔的应用前景.

Study on New Type of Ahead Spacer Fluid System before Cementing

Normal spacer liquid can not solidify that forms micro clearance and micro annulus in the interface of casingwall-cement ring-well wall, which influences the cementing quality seriously.In this paper, a type of spacer fluid systemis developed that can solidify by itself, and the densities can be adjusted from 1.3 g/cm3 to 2.4 g/cm3, the fluidity can becontrolled between 19 cm to 23 cm at the temperatures of 50 ℃ to 90 ℃.The compressive strength can reach 8 MPa after 24hours with adjustable thickening time, also this system has good compatibility with drilling fluid and cement slurry, and thewhole compressive strength of the three phases can reach more than 8 MPa after 48 hours, which improves the cementingquality apparently.