1.PrincipleThe mudstone density meter is an instrument to measure the density of mudstone.By measuring the density of mudstone, you can know the pressure change of drilled strataand predict the possible formations with abnormal pressure. The abnormal pore pressure of formations is extremely dangerous to oil wells and it may cause accidents such as well kick, well blowout, well lost, shrinkage of borehole diameter, bit freezing and so on. Characteristics of mudstone to produce ultra high pressure are that the density of mudstone decreases, deviating from normal density trend line of mudstone. In general, the resistivity and acoustic velocity of formations with abnormal pressure are also different and as a result, the resistivity log and acoustic log can be used to detect them. But these log curves can be obtained only after the drilling is complete. Therefore, a method to immediately predict ultra high pressure formations is required, namely, the method to measure the density of mudstone is used to predict abnormal pore pressure of formations.2.Compositionand technical indicators of instrumentComposition of instrument2N01G type density analyzer of mudstoneconsists of:organic glass cylinder, scale subdivision in the mirror plane, fixing mirror bracket, stainless steel pole, floater, damping hammer, zero setting knob and so on.Technical indicatorsMeasuring range: 1-3g/cm3The minimum sample weight: 0.05gResolution: 0.03 g/cm3