Fracturing stimulation is a major means to effectively develop and produce Daqing low permeability reservoirs. Although large–scale fracturing has better results in Daqing oilfield, the construction cost is high priced and it is difficult to achieve efficiency exploit. To improve the low permeability reservoir production effect,using fiber temporary plugging in multi–branch fractures is a good method which can improve the artificial fracture oil drainage area. Through laboratory experiments, the properties of the fibers were evaluated and the conditions for the formation of branch cracks were clarified. Combined with numerical simulation and field construction requirements, the good transferring timing of within fractures and the construction time were made clear, the number and length of transferred fractures were optimized, and then the design method of multi–branch fracturing technique of low permeability reservoirs by fiber temporary plugging within fractures was determined.The fracturing technique not only insured the modification effect but also effectively control the construction cost and relized economic and effective exploitation of low permeability reservoir, which was successfully applied in 18 wells of Daqing peripheral low permeability reservoirs and achieved a good effect.

Key words: fracturing; low permeability reservoir;degradable fiber; temporary plugging; branch fractures