Abstract:
In order to improve the sealing hole quality of through beds borehole and ensure the effect of regional gas control, aiming at the problem that gas drainage pipe was compressed and blocked in the process of borehole sealing, resulting in the closure of the gas flow channel, by analyzing the factors affecting the external pressure resistance of drainage pipe, a non-metallic drainage pipe external pressure resistance test device based on temperature and external pressure parameters is developed to simulate the deformation law of the extraction pipe under external pressure in underground grouting process. The results show that the material, outer diameter, wall thickness, ambient temperature and applied pressure all have influence on the deformation of the extraction pipe. When the material, diameter and wall thickness are fixed, the main influencing factors of the deformation are the external pressure and the ambient temperature. At the same temperature, the higher the pressure is, the more serious the deformation of the extraction pipe is; the higher the temperature is, the lower the pressure when the extraction pipe is flattened. For PE-KM1.6/32 pumping pipe with wall thickness of 3.4 mm, when the rock hole temperature is 20 ℃ to 30 ℃, the grouting pressure should not exceed 1 MPa.