Research On Soluble Bridge Plug And Test Tools

70% of the oil and gas reserves in China are unconventional reservoirs.With the development of oil and gas resources,the unconventional oil and gas resources with great potential have gradually entered the people’s vision.Horizontal well staged fracturing technology is an effective means to improve the recovery rate of unconventional reservoirs.The characteristics of soluble bridge plug,such as no drilling,no fishing and self dissolving without any measures,make it more potential than traditional bridge plug in reducing operation cost and operation cycle.Based on the investigation of the application of soluble bridge plug at home and abroad and consulting a large number of literature,this paper summarizes the performance requirements of downhole tools for soluble metal materials,designs the soluble metal materials with Al as the matrix element and its preparation process according to the requirements,and makes them meet the mechanical and solubility requirements by controlling the content of trace elements,the metallography,density,hardness,strength and dissolution rate of the material were tested.According to the design principles and working conditions,the bridge plug structure design was completed,and the key parameters of key parts,such as slip,rubber cylinder,central pipe and pin,were checked and calculated,and ANSYS finite element simulation was carried out.This paper also designs a calculation method for the displacement of pumping tools in horizontal wells,analyzes and verifies the main influencing factors of pumping displacement.After the production of the soluble bridge plug prototype,the indoor test scheme was developed to test the performance of the soluble bridge plug.According to the designed indoor test scheme,the pressure balanced small diameter hydraulic setting tool and other related tools were designed.Then,under the set working conditions,the performance indexes of slip compressive strength,whole machine strength and dissolution time were tested,which proved the rationality of the design of soluble bridge plug and related tools,and laid the foundation for the future field test.The designed soluble bridge plug has been used in a single well for 3 times,and the fracturing process has been carried out smoothly.After the blowout,the bridge plug has not been blocked.It was verified that the bridge plug has been completely dissolved and the wellbore has good connectivity.The test results have reached the expected effect of the design.