PLUGGING FRACTURE LOST CIRCULATION ZONE OF HORIZONTAL WELL USING TEMPORARY SHIELDED TECHNOLOGY

The horizontal and large angle sections of HW702 horizontal well of Kelamayi oil field drilled through Jiamuhe reservoir of Permian with vertical fractures. For safely drilling and preventing poy zone from damage, the temporary shielded plugging drilling fluid which mated with superfine calcium carbonate and sulfonated asphalt added with compounded ion is used. The experiments of coring samples in laboratory have shown the permeability reduced to 0 after temporary shielded plugging and the plugging depth were less than 3 cm that can be unplugged by acidizating and performating. The appiication shown the good results in working site in HW702 well which have gotten commercial oil.