Abstract:
The effective disposal of complex wells is the key to ensure the sealing integrity of underground gas storage. Nanpu 12-198 well is a difficult disposal well within the scope of Nanpu 1-29 gas storage reservoir construction. The old well has multiple side drilling holes. One of the side drilling holes penetrates the cap rock and connects with the reservoir, with a risk of lost circulation and overflow. If the plugging cannot be effectively implemented, it will affect the sealing and operation safety of the gas storage. The length of the drilling tool in the wellbore is about 1 163 m, and it is difficult to complete the operation by conventional methods. By means of drilling new rescue wells, using gyroscope and domestic passive magnetic guidance technology, the azimuth and distance between the rescue well and the old borehole falling fish are accurately determined, and the re-entry of the fish bottom and the open hole section of the old borehole is realized, and the well bottom is successfully drilled to complete the plugging target. The successful re-entry of the well has explored an effective way for the disposal of complex wells in domestic gas storage.