澳门银河赌场注册送38-澳门银河赌场招人好招吗_百家乐德州_全讯网下载 (中国)·官方网站

Abstract: Lost circulation critically jeopardizes drilling safety and efficiency, and remains an unresolved challenge in oil and gas engineering. In this paper, by utilizing the self-developed dynamic plugging apparatus and synthetic cores containing large-scale fractures, experimental research on the circulation plugging of different materials was conducted. Based on the D90 rule and fracture mechanical aperture model, we analyze the location of plugging layer under dynamic plugging mechanism. By setting different parameters of fracture width and injection pressure, the laws of cyclic plugging time, pressure bearing capacity and plugging layers formation were investigated. The results show that the comprehensive analysis of particle size and fracture aperture provides an accurate judgment of the entrance-plugging phenomenon. The bridging of solid materials in the leakage channel is a gradual process, and the formation of a stable plug requires 2–3 plug-leakage cycles. The first and second cyclic plugging time was positively correlated with the fracture width. Different scales of fractures were successfully plugged with the bearing pressure greater than 6 MPa, but there were significant differences in the composition of the plugging layer. The experimental results can effectively prove that the utilized plugging agent is effective and provides an effective reference for dynamic plugging operation.