Drilling technology for parallel relief well of Well Wen 23-6J

Wen-23 gas pool has thick caprock and small burial depth, and has favorable conditions for building gas storage. However, this block already has Well 23-6X, which has been abandoned, but it affects the sealing of the gas pool because it penetrates the caprock. Therefore, successful plugging of this well is a key to building the gas storage. In 2010, six holes were drilled in the upper formation of Wen 23-6X in four months, but they all failed in locating the fish head. In 2013, the distance correction technology with magnetic measurement was first introduced from British Scientific Drilling Company and tried to drill parallel relief well Wen 23-6J and to connect with Wen 23-6X from below the fish bottom. For nearly six and half months, five holes were drilled in the lower formation, tagged fish bottom twice, crossed with the old hole three times, located the azimuth and complex perforation and cement squeezing were conducted in the fifth hole. Negative pressure test showed that the Wen 23-6X was successfully plugged and met the requirement for gas storage building in Wen 23 gas pool.