Design and analysis of experimental device for rock porosity

In order to improve the accuracy of rock porosity test results and optimize the experimental teaching effect, this paper improves the porosity tester based on the two-chamber method of Boyle's law, and puts forward specific measures to improve the test accuracy. The coal rock of Zhaozhuang Mine in Shanxi Province, the shale and coal rock of Wannian Mine in Hebei Province, and the sandstone and coal rock of Yongcheng in He’nan Province are selected for test and analysis. The results show that the air tightness of the device, temperature change and sample drying time are the key factors affecting the accuracy of porosity test. The rock with poor pore connectivity and small porosity has higher requirements for the air tightness of the device, and the test time needs to be increased. During the experiment, the fluctuation of the ambient temperature will affect the test value, and the temperature correction is needed. The drying time of coal rock is about 48 h, and the drying time required for the quality of sandstone, shale and oil shale to achieve basic stability is shorter.