Preliminary Research on Detection Method for Connecting Relief Well to Blowout Well

At present drilling relief well is the most reliable method to completely solve serious blowout accidents,and it is a key link to accurately detect relative position of relief well and blowout well.In order to connect relief well to blowout well successfully,calculation method of using detection tool to connect relief well with blowout well was studied in this paper.Blowout well casing was approximated to a cylinder,through analyzing the spread and attenuation pattern of current injected by down-hole electrode and then concentrated on blowout well casing,the calculation method to determine the distance and orientation from relief well to blowout well was obtained,and meanwhile illustrated the influences of some parameters on detection accuracy of this tool,such as the magnitude of current injected by down-hole electrode and the spacing of down-hole electrode and sensor.The results showed that this detection tool and calculation method of determining distance and orientation from relief well to blowout well can guide relief well to connect to blowout well vertically or laterally.It was concluded from analysis that the detection tool for connecting relief well to blowout well could meet engineering requirement of steerable drilling of relief well essentially.