Narrow-density window stratum safety drilling control system based on underground hydrocarbon detection

Abstract

The invention provides a narrow-density window stratum safety drilling control system based on underground hydrocarbon detection. The control system comprises a wellbore hydrocarbon substance monitoring unit, a well bottom leakage detection unit and a well bottom pressure control unit, the wellbore hydrocarbon substance monitoring unit can judge whether stratum hydrocarbon substances enter a wellbore or not, and the well bottom leakage detection unit can judge whether underground leakage occurs or not; the bottom hole pressure control unit can adjust the bottom hole pressure; the bottom hole pressure control unit can control the bottom hole pressure according to the judgment result of the wellbore hydrocarbon substance monitoring unit and the judgment structure of the bottom hole leakage detection unit until no stratum hydrocarbon substance enters a wellbore and no well leakage occurs, and the bottom hole pressure control unit keeps the current bottom hole pressure unchanged. The beneficial effects can comprise the step that the control system achieves fine control over the bottom hole pressure through the downhole hydrocarbon detection technology and the leakage detection technology.

Description

technical field [0001] The invention relates to the field of wellbore pressure control for oil and gas well drilling, in particular to a control system for safe drilling in formations with narrow density windows based on downhole hydrocarbon detection. Background technique [0002] At present, the main engineering risk in the field of deep well drilling is concentrated in the well control risk, and the essence of the well control risk is to control the bottom hole pressure to be greater than the pore pressure of the formation, so as to prevent a large amount of formation fluid from entering the wellbore. The bottomhole pressure control of traditional drilling technology is extremely rough, with an error of 5-10MPa. At present, the drilling and completion of deep and ultra-deep wells is faced with the problem of a narrow safe density window. Large bottomhole pressure fluctuations can easily cause downhole overflow and lost circulation, resulting in well control risks and redu...

AI Technical Summary

Problems solved by technology

For example, one of the objectives of the present invention is to provide a control system for safe drilling in formations with a narrow density window based on downhole hydrocarbon detection, so as to solve the problem of a narrow safe density window in the drilling and completion of deep and ultra-deep wells