KEY DRILLING TECHNOLOGY OF 4000M ULTRA LONG HORIZONTAL WELL IN TIGHT GAS RESERVOIR OF CHANGQING OILFIELD, CHINA

The practice at home and abroad shows that the long horizontal section drilling technology is the main means to improve the single well production and reduce the drilling cost. In view of the difficulties of large friction torque and immature completion technology in long horizontal section drilling, through the stress analysis of drilling tools, optimization of trajectory control technology, research and development of low friction drilling fluid system, and cementing matching of narrow gap and long horizontal section, a safe drilling technology suitable for Changqing tight gas reservoir is formed. The drilling depth of the test well JingX reached 7388m, and the horizontal section was 4118m long, which created the record of the longest horizontal section on land in Asia Pacific region, which has demonstration significance for similar gas reservoirs in China.