CEMENTING TECHNOLOGY OF FOAM CEMENT SLURRY

Huatugou Oilfield has been developed for years, thus the formation pressure coefficient is extremely low, only of 0.6~0.8; moreover, shallow gas exists in the zone of 80~150m to the surface, therefore complete zonal isolation is required for the pay zone cementing, with cement top at the surface. Adjustment wells are drilled for further development, and most of the wells are around 1300m. Cementing quality was poor in this area, and it severely limited the development of this Oilfield. To solve this problem, the foam slurry cementing technology was studied and used in the pay zone isolation of 5 wells. The cementing operation was smooth and no lost circulation was found, and acoustic amplitude logging proved that the cementing qualities were excellent.. This novel lightweight cement solves such problems as cementing the low pressured and lost circulation well, long interval isolation and heat production well; furthermore, it improves the cementing quality, shortens the well construction period and cuts down the cost.