Process Principle: This technology is primarily used for drilling in soft and broken coal seams in underground coal mines, effectively addressing the challenges of hole formation and hole protection. The drilling rig is equipped with two sets of tool strings: drill pipes and external casings. During drilling, the drill pipes advance while the casings remain stationary (water is simultaneously injected through the center of the drill pipes and the annulus between the drill pipes and casings). After reaching the designed hole depth, the central drill pipes are withdrawn, leaving the hole-protecting casings in place. Screen pipes are then lowered through the entire length of the casing, after which the casing is removed. This achieves full-hole-section screen pipe installation with casing protection for directional long boreholes, ensuring successful hole formation and improving the utilization rate of gas extraction from the boreholes.

Product Features:

①The rig is equipped with an automatic drill pipe loading mechanism, enabling automatic installation and removal of drill pipes and casings, which reduces the labor intensity of operators.

②The feed thrust and pulling force of the rig are not less than 200KN, facilitating the handling of special downhole conditions.

③The rig is equipped with a remote control operating system, allowing operation from a distance with flexible and reliable control to ensure safe positioning for operators.

④The rig can achieve "casing-following hole protection" drilling, improving the success rate of hole formation and the depth for lowering screen pipes.