PROCESS OF HOLE DRILLING Russian patent published in 2001 - IPC

FIELD: oil and gas industry, geology, public utilities. SUBSTANCE: invention can also be used in some other branches of industry while drilling for oil, gas, water and other mineral resources in carbonate formations. Liquid harmless for soil, for instance, river water is used as flushing fluid while drilling holes in carbonate formations, it is injected with reagent-stabilizer preserving formation properties. Pressure in shaft of hole is kept not less than formation pressure during drilling. When drilling string is lifted flushing fluid is continuously added to preserve level of day surface when pipes are joined. Lubricant based on mineral oils is used to lubricate threaded connections. Drilling waste lifted from shaft of hole is used in the capacity of soil fertilizer in arable lands. Water- soluble salts, for example, potassium chloride, in the amount of 10 to 30% of volume of flushing fluid. EFFECT: complete utilization of drilling waste when holes are sunk in carbonate formations, ecologically clean drilling technology, reduced usage of materials. 2 cl