Intelligent Directional Drilling Technology Research And Engineering Demonstration Project for Broken Soft Coal Seams in Wuhai Mining Area Undertaken by CCTEG Xi'an Research Institute Passed Acceptanc

Coal seams in the Wuhai Mining Area are generally characterized by fragmentation, soft texture and low gas permeability. Conventional hydraulic directional drilling technology encounters multiple challenges in such formations, including poor hole-forming performance, low trajectory control accuracy, and insufficient automation and intelligence of equipment.

In addition, traditional construction methods are incapable of real-time formation condition perception, featuring single monitoring parameters and backward data analysis approaches. These drawbacks result in low efficiency and high safety risks for gas control engineering.

To address the above challenges, the project team of CCTEG Xi'an Research Institute has systematically carried out research on pneumatic directional drilling technology for broken soft coal seams and conquered a number of key core technologies. The research has greatly improved the trajectory control accuracy, hole-forming rate and coal seam penetration rate of directional boreholes, delivering a complete intelligent solution for directional drilling in broken soft coal seams.

The research achievements of this project have been applied in large-scale engineering demonstration at Luotuoshan Coal Mine of Wuhai Energy. The maximum borehole depth reached 651 meters, setting a new national record for underground pneumatic directional drilling depth in coal mines. The comprehensive hole-forming rate hit 87.5%, with an average monthly drilling efficiency of 2,060 meters per rig.

Compared with conventional construction technologies, the new technology greatly boosts the gas drainage efficiency in broken soft coal seams and effectively reduces gas disaster risks, laying a solid foundation for safe mine production. Meanwhile, it remarkably improves the economic benefits and management level of drilling construction.