초록 ▼

The present invention provides cementitious well drilling fluids and methods of drilling subterranean well bores. The drilling fluids are basically comprised of water, a water viscosity increasing material and a cementitious material which when deposited on the walls of the well bore as a part of th

The present invention provides cementitious well drilling fluids and methods of drilling subterranean well bores. The drilling fluids are basically comprised of water, a water viscosity increasing material and a cementitious material which when deposited on the walls of the well bore as a part of the filter cake thereon consolidates the filter cake into a stable mass that readily bonds to a cementitious material slurry subsequently placed in the well bore. The methods of drilling a subterranean well bore are basically comprised of the steps of preparing a drilling fluid of the invention and drilling a subterranean well bore using the drilling fluid.

대표청구항 ▼

[ What is claimed is:] [1.] An improved drilling fluid for use in drilling a subterranean well bore which forms fluid loss reducing filter cake on the walls of the well bore comprising:water;a water viscosity increasing material selected from the group of hydratable polymers, uncalcined clays and mi

[ What is claimed is:] [1.] An improved drilling fluid for use in drilling a subterranean well bore which forms fluid loss reducing filter cake on the walls of the well bore comprising:water;a water viscosity increasing material selected from the group of hydratable polymers, uncalcined clays and mixtures thereof; anda cementitious material which when deposited on the walls of said well bore as a part of said filter cake is caused to harden and consolidate said filter cake into a stable mass that readily bonds to cement used for primary cementing subsequently placed in said well bore.[ Class C fly ash combined with a set retarder, A][ Class F fly ash combined with a set retarder and an activator selected from the group consisting of hydraulic cement, lime and an alkali, a calcined clay which forms a cementitious material combined with a set retarder and an activator selected from the group consisting of a hydraulic cement, lime and an alkali, and a siliceous containing substance which forms a cementitious material combined with a set retarder and an activator selected from the group consisting of a hydraulic cement, lime and an alkali.][ Class F fly ash, a calcined clay and a siliceous containing substance.][ Class C fly ash combined with a set retarder, A][ Class F fly ash combined with a set retarder and an activator selected from the group consisting of a hydraulic cement, lime and an alkali, a calcined clay which forms a cementitious material combined with a set retarder and an activator selected from the group consisting of a hydraulic cement, lime and an alkali, and a siliceous containing substance which forms a cementitious material combined with a set retarder and an activator selected from the group consisting of a hydraulic cement, lime and an alkali.][ Class F fly ash, a calcined clay and a siliceous containing substance, and said activator is selected from the group consisting of a hydraulic cement, lime and an alkali.]