| 摘要 |
A method of filling up the borehole (1) with the drilling mud while lowering and raising the drilling pipes (2) during the process of drilling the borehole (1) consists in feeding the drilling mud from a filling reservoir (3) into the borehole (1) through a measuring tank (4) interconnected with them. The space above the drilling mud in the filling reservoir (3) is evacuated and connected with the measuring tank (4), the process of filling up being controlled by way of decreasing the vacuum degree in the filling reservoir (3) by allowing portions of air to enter therein, those portions coming from the mouth of the borehole (1) when the level of the drilling mud therein lowers below the point of interconnection of the measuring tank with the mouth of the borehole, the specific gravity of the feeded drilling mud being simultaneously decreased by way of aeration thereof.
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