Downhole pressure control method based on downhole hydrocarbon detection

Abstract

The invention provides a downhole pressure control method based on downhole hydrocarbon detection. The method comprises the steps that whether stratum hydrocarbon substances intrude into a wellbore exists at the bottom of a well or not is monitored in real time through a downhole hydrocarbon detection tool in the drilling process, meanwhile, whether downhole leakage occurs or not is monitored, when stratum hydrocarbon substances intrude into the wellbore, the bottom hole pressure is adjusted until it is monitored that stratum hydrocarbon substances cannot enter the wellbore, when downhole leakage occurs, the bottom hole pressure is adjusted until downhole leakage cannot be monitored until it is monitored in the wellbore that no stratum hydrocarbon substance enters the wellbore and no wellleakage occurs, and the bottom hole pressure is kept unchanged. The method has the beneficial effects that under the condition that stratum hydrocarbon substances are guaranteed, it can be guaranteedthat the well does not leak, and fine control over the bottom hole pressure is achieved.

Description

Technical field[0001]The present invention relates to the field of wellbore pressure control for oil and gas well drilling, in particular to a bottom hole pressure control method based on downhole hydrocarbon detection.Background technique[0002]At present, the main engineering risks in the field of deep well drilling are concentrated on well control risks, and the nature of well control risks is to control the bottom hole pressure to be greater than the formation pore pressure to prevent a large amount of formation fluid from entering the wellbore. The bottom hole pressure control of traditional drilling technology is extremely coarse, with an error of 5-10 MPa. However, the current drilling and completion of deep and ultra-deep wells are facing the problem of a narrow safety density window. Large bottom hole pressure fluctuations can easily cause downhole overflow and lost circulation, resulting in well control risks and reducing the timeliness of production operations. At present,...

AI Technical Summary

Problems solved by technology

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, and large bottomhole pressure fluctuations can easily cause downhole overflow and lost circulation, resulting in well control risks and reducing the timeliness of production operations

At present, the common method at home and abroad is to install a downhole pressure monitoring device (PWD) in the downhole, but the safe position of the tool is not at the bottom of the well, and affected by the pressure calibration accuracy of the sensor, the error of the monitoring accuracy of the real value of the downhole pressure is also relatively large (2 -3MPa), has a certain reference value, but is affected by tool stability and price, and the scope of promotion is small, and the promotion and application of this tool is relatively seldom