Development of an In-Situ Simulation Device for Testing Deep Pressure-Preserving Coring Tools under High-Temperature and Ultrahigh-Pressure Conditions

Abstract

With the increasing mining depth of deep mineral resources, the underground temperature and pressure also increase, which requires more advanced mining equipment. Therefore, to adapt to the special application scenario of the research and development of pressure-preserving coring tools under the extreme environmental conditions of deep strata, in this study, an in-situ simulation device under high-temperature and ultrahigh-pressure conditions is developed. The principles and methods of applying temperature and pressure to the device are expounded. Furthermore, the two main modules of the device are analyzed and studied experimentally. On the one hand, a segmented simulated coring test cabin is constructed, and pressure testing of the test cabin is carried out. The results show that the test cabin with inner diameters of 150 mm and 500 mm runs stably under the working condition of a pressure up to 190 MPa (considering the influence of temperature of 150 °C), and the cabin remains in the stage of elastic deformation. There is no leakage of pressure or fluid in the whole test process. On the other hand, the performance of the driving module is tested. The results show that the driving module can provide a stable rotation speed of up to 150 r/min when the sealing pressure is 140 MPa. Therefore, the device can be applied to carry out simulated coring test and is suitable for the research and development of pressure-preserving coring tools in deep extreme environments, which may promote the development of deep mining engineering.