CEMENTING COMPOSITION FOR OIL AND GAS WELLS OVERHAUL

摘要

The invention relates to a cementing composition intended to be used, in particular, but not exclusively, for operations of cementation - squeeze cementation, plug cementation or abandoning cementation - or of overhauling in oil and gas production wells, preferably but not necessarily, for squeeze cementation performed in the operations of abandoning non-productive zones, isolating problematical zones while drilling, repairing drilling fluid or gas conduits in primary cementation or repairing fractures in casing columns. According to the invention, the composition consists of a binder material, API G class cement, 1%, as related to the cement weight, reducing agent for filtration and colloidal support, acrylamide-dimethylacrylamide copolymer; 1.5...2.5% insulation and adherence improving material, sodium silicate as related to the cement weight; 1.5...3.5% calcium chloride accelerator, as related to the cement weight and, depending on the temperature, 0.15% antifoaming agent, silicon-based organic compound, as related to the cement weight, as well.