The Development Of Supporting Tools For Multistage Staged Fracturing Technology

With increasing domestic energy demand and the deepening of oilfield exploration and development,in order to provide oil and gas production stably,unconventional exploration and development of oil and gas reservoirs become the next major goal.Among them,the offshore oil and gas reservoirs resources occupy a non-negligible proportion of the total reserves of oil and gas resources in our country,and with the maritime discoveries of new reservoirs,this proportion continuing to rise.Therefore,the focus of a growing number of oil and gas development companies began to shift to the sea from the land,from the shallow water toward the deep development.Newly discovered offshore reserves of oil and gas reservoirs are mainly low permeability,these reservoirs features are low-production,high-pressure level,difficult mining and so on.In order to improve well production and reservoir development efficiency,reduce fracturing operation period,reduce reservoir damage,multistage fracturing technology has become the primary means of developing low permeability reservoirs.Unlike multistage fracturing on land,the fracturing equipment and tools for sea fracturing need to left in the three materials used work ship or fracturing ship,so the operating time for the replacement of fracturing equipment and fracturing work takes a long time and difficulty.Moreover,the replacement string fracturing operation likely to cause secondary reservoir pollution,which increasing fracturing costs.When operating the fracturing flow back,the increasing of wellhead pressure and decreasing of flow-back efficiency may lead to flow-back operation fail or even cause accidents,if the flow-back ball not promptly removed easily.In view of this,to carry out research about high-pressure fluid loss isolation barrier valve and wellhead ball precipitator for the multistage fracturing operation.This paper sums up the characteristics of the fluid loss isolation barrier valve and wellhead ball precipitator,after analyzing the multistage fracturing technology of horizontal well and the supporting tools.Combining the characteristics of multistage fracturing operation conditions,the paper has designed a fluid loss isolation barrier valve and wellhead ball precipitator based on the original device.The paper details the structure of fluid loss isolation barrier valve and wellhead ball precipitator,checking the strength of its key components by theoretical analysis and ANSYS software.After the results satisfied to the strength requirements,manufacturing production of fluid loss isolation barrier valve and wellhead ball precipitator for laboratory experiment to validate their performance and provide a basis for future field applications.