Ultra-Deep Well Drilling Technology in the Igneous Invasion Coverage Area of the Shunbei Oil and Gas Field

When drilling ultra-deep wells in the igneous invasion area of the Shunbei Oil and Gas Field, challenges such as lost circulation in the Permian igneous rock, borehole collapse in the Silurian mudstone and poor drillability in deep Paleozoic strata are commonly encountered. In addition, the large collapse pressure of igneous invasion layer also brings new drilling problems. Previously, this oil and gas field tried to increase the drilling fluid density to alleviate the borehole collapse in igneous invasion and optimize the casing program design to specifically seal the igneous invasion, but the effect was limited. The size of completion borehole is only 120.7 mm, and the failure rate of directional drilling tools is high, which leads to low drilling efficiency. In order to solve the above-mentioned common problems and new problems in the ultra-deep well drilling of this area, a formation tri-pressure profile was established, the necessary sealing points and casing sequence were analyzed, and the original completion borehole size was expanded from ϕ120.7 mm to ϕ143.9 mm, hence optimizing the casing program in the igneous invasion coverage area. The Permian leakage prevention technology, the Silurian borehole stabilization technology, igneous invasion safety drilling technology and zonal drilling acceleration technology were developed and integrated into the ultra-deep well drilling technology for rock invasion coverage area of the Shunbei Oil and Gas Field. This integrated technology was successfully applied in 7 ultra-deep wells, which reduced the drilling cycle significantly and improved the ROP largely, indicating that it could solve practical problems properly and is of significant application value.