As the main weighting agent of oil?based drilling fluids, barite has many problems with high?density oil?based drilling fluids. In order to explore the applicability of micro?manganese mineral powder in oil?based drilling fluids. The particle size distribution and microscopic morphology of barite and micro?manganese ore powder were analyzed by laser particle size analyzer and scanning electron microscope. The differences in rheology, water loss and wall?building, lubricity, settlement stability, and reservoir protection performance between barytic petroleum?based drilling fluid system and micromanganese slag oil?based drilling fluid system were studied. The results show that under the condition of low density, the difference between the micromanganese ore powder system and the barite system is small; under high density conditions, the micro?manganese ore powder system has low viscosity and high cutting, the viscosity coefficient of the mud cake is less than 0.10, the sedimentation density difference is less than 0.03 g/cm3, and the permeability recovery rate after acid dissolution is higher than 95.00%. Its rheology, lubricity, sedimentation stability, and reservoir protection performance are better than the barite system, but compared with the barite system, the micro?manganese ore powder system has a large water loss and poor mud cake quality. It is recommended to compound the micro?manganese ore powder with a weight Spar to improve the water loss of the system. The research results fully reveal the difference in performance between the micro?manganese mineral powder oil?based drilling fluid system and the heavy crystal oil?based drilling fluid system, and provide support for the micro?manganese mineral powder to improve the performance of high?density oil?based drilling fluids, and also increase the weight of high?density oil?based drilling fluids. It also provides a new development direction for the application of ultra?high density oil?based drilling fluid weighting agents.
