关键词: 管井钻孔, 近千米钻孔, 强厚含水层, 钢基复合保温套管

Abstract: Abstract: Refrigeration and cooling were effective technical means for preventing and controlling thermal hazards in deep mines. During the construction of the refrigeration and cooling system in the Walnut Valley mine, there were several technical difficulties need to be solved, such as deep drilling of the cooling tube well, passing through the thick and strong aquifer of the Luohe Formation, and long-distance transportation of refrigerant for cooling. Based on the analysis of engineering and hydrogeological conditions, the article determined the design parameters for the two-stage opening and segmentation of the pipe well drilling.After conducting a research on the performance of pipeline cold insulation materials, the article proposed a design scheme for the protective wall pipe in the bedrock section under four cold insulation methods: composite steel pipe, static air, glass microsphere reinforced cement, and steel-based composite thermal insulation casing.Taking into comprehensive consideration factors such as cold insulation effect, cementing reliability, and construction difficulty, the steel-based composite thermal insulation casing was selected as the preferred option for the working pipe.According to the force calculation of the casing, the specifications and parameters of the protective wall pipe were verified.The implementation effect of the project shows that the temperature loss at the beginning and end of the downcomer on the well is about 1 °, which can meet the requirements of cooling capacity loss for long-distance transportation of refrigerant, and has promotion and application value for similar projects.