Further Study On Annular Sand Fracturing Technology Of Coiled Tubing Sandblasting Perforation

In recent years,the proven reserves of low-permeability tight reservoirs in our country account for more than 50% of the total newly proved reserves.How to effectively utilize the reserves of low-permeability tight reservoirs and improve production efficiency to meet the needs of China's national economic development is an important and urgent task facing China's oil industry.At present,hydraulic sand fracturing technology has become an important means to effectively develop low-permeability tight oil and gas reservoirs.After years of research and practice by scholars at home and abroad,great progress has been made in the research of fracturing fluid system,proppant and fracturing tools.However,it still faces many problems,especially for the reservoirs with many vertical upper layers and large span,the conventional method is adopted The fracturing method of layer by layer up return or mechanical partial pressure has the phenomenon of long construction period and easy to occur downhole accidents.Therefore,it is necessary to seek a new hydraulic sand fracturing technology to improve the efficiency of layer transfer operation and improve the pertinence of the transformation.At the same time,with the continuous development of the horizontal well staged fracturing technology,in order to further improve the effectiveness of the horizontal well staged fracturing balanced transformation,shorten the operation cycle,improve the operation efficiency,and increase the reserve production degree,the annular sand fracturing technology of horizontal well coiled tubing with bottom seal hydraulic sand blasting perforating oil casing is to realize the sustainable economic and effective development of horizontal wells in tight low permeability oil and gas fields One of the key technologies.In view of the problems existing in the annular sand fracturing technology of hydraulic sand blasting perforation with bottom seal of coiled tubing,this paper studies the development trend and technical status of coiled tubing at home and abroad,optimizes the composition and key tools of coiled tubing layered fracturing system,and combines with the laboratory experimental study of nozzle sandblasting jet casing opening,using the relationship between jet displacement,nozzle pressure drop and jet velocity According to the calculation of the friction in coiled tubing and annulus,the nozzle diameter and number of nozzles are optimized,and the calculation chart of the relationship between nozzle pressure drop,displacement an jet velocity is established.Finally,the annular sand fracturing technology of coiled tubing hydraulic sandblasting perforation casing is formed by optimizing the type of packer,setting mode and layer transfer mode Through field application and post fracturing evaluation analysis,a relatively mature and perfect coiled tubing separate layer fracturing technology system for horizontal wells in tight oil and gas fields has been formed,which provides technical support for further improving the development effect and reservoir reconstruction technology level.