摘要
提出了两种以MgO为主的复合膨胀剂MC-1,MC-2。膨胀剂加量为6％时水泥浆的膨胀率可达2.67％。硬化后的水泥石具有良好的酸溶性和一定的抗压强度,能满足修井、堵漏施工和施工中保护油气层的技术要求。本研究工作表明:MgO水化消解时的体积增殖和MgO晶体的热膨胀是产生大膨胀率的主要原因。还讨论了水灰比、缓凝剂对膨胀率的影响。
Two compounded expansive agents based on magnesium oxide and FDN,MC-1,and MC-2, are studied in laboratory.The swelling(expansion)of grade G oil well cement slurries at initial setting increases with the amount of agent added and expansion 2.67% is obtained for the sturry of water-to-cement ratio 0.6 and MC-1 or MC-2 content 6%. With increasing MC amount the initial setting time and fluidity of the slurries and the set cement strength decrease in an acceptable degree. The set retarders tested decrease the swelling of MC-treated cement slurries in different extents. MCs significantly enhance the solubility of set cemsnt in HCl-acid of various concentrations (1%, 5% and 15%). These agents can be recommended for use in workover operations and lost circulation treatments with cement slurries. It is stated that the swelling of the magnesia cement slurries can be explained by the volume dilalance of cement components during hydration and the thermal expansion of MgO crystallites.
出处
《油田化学》
CAS
CSCD
北大核心
1992年第4期297-301,共5页
Oilfield Chemistry
关键词
水泥
膨胀剂
氧化镁
油井
Expansive Agents for Cement, Magnesium Oxide, Magnesia Cement, Mechanisms of Expansion, Laboratory Performance Evaluation
