Horizontal well drilling technology for variable-diameter reamer bit to drill through goaf along with pipe

• Main Authors: YANG LU, DONG WENKUI, WANG JUNBANG, DONG BOYANG, GAO JINGJING, SONG BAIQIANG, ZHANG JINLING, CHEN JUNXIA
• Format: Patent
• Language: Chinese; English
• Published: 23.06.2023
• Subjects: EARTH DRILLING; EARTH DRILLING, e.g. DEEP DRILLING; FIXED CONSTRUCTIONS; MINING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR ASLURRY OF MINERALS FROM WELLS

The invention relates to the technical field of coal bed gas drilling processes, and discloses a horizontal well drilling technology for a variable-diameter reamer bit to drill through a goaf along with a pipe. Comprising a follow-pipe upper part, a releasing part arranged on the follow-pipe upper part, and a variable-diameter reamer bit and a conventional bit which are positioned at the end of the follow-pipe lower part, and a follow-pipe drilling method for crossing a goaf by using the drilling tool in a four-opening well completion manner. In addition, torque transmission and hand release are achieved by designing a professional hand release structure, and large-diameter rock debris is avoided. According to the method, the problem that the lower coal seam is mined through the goaf is well solved, and the same technology can be used for salt well development and can also penetrate through the salt layer of the upper goaf to develop the lower salt layer. 本发明涉及煤层气钻井工艺技术领域，公开了可变径扩孔钻头跟管钻穿采空区的水平井钻井技术，本发明通过设置穿越采空