Study On Casing Hole Formation Tools Of Radial Drilling Technology

Radial drilling technology can also be called ultra-short radius radial horizontal well technology,which provides an economic and effective way for the development of low permeability reservoirs.The technology can be divided into two stages: casing hole formation and radial horizontal drilling.Casing hole formation provides passageways for radial horizontal drilling and fluid which flows into the wellbore.In order to improve the efficiency and applicab ility of the casing and ensure that the operation of radial horizontal drilling can proceed smoothly,this paper proposed a novel casing hole formation tool.The details are as followings:(1)Designed the scheme of casing hole formation.Considering the problems and shortcomings of current casing hole formation tools,a new scheme of casing hole formation is proposed.The selection of various components,such as coiled tubing,universal joint,hydraulic motor,drill,anchor and the design of whipstock are completed.(2)Design and optimization of the trajectory of the whipstock.Through the finite element software ABAQUS,the steering resistance of the high pressure hose passing through the whipstock is studied.Influences of turning radius,bend radius,bend angle guide and other parameters on the steering resistance have been studied.Besides a better trajectory of the whipstock is designed which has a lower steering resistance.As a result,the power consumption of nozzle inlet reduced and maximum level of footage increased.Finally,the production of the oil field is promoted.(3)Match and optimization of drilling pressure and cutting speed.Cutting processing is analyzed.The influence of cutting force and cutting speed on the opening process is analyzed.According to the analyses above,operation parameters are optimized.Reasonable drilling pressure and cutting speed are chosen.Selections of the motor and injection displacement are completed.Finally,the operation parameters are in the optimal level.(4)Study on the feasibility of the scheme.Through a preliminary laboratory test,the feasibility of the scheme is verified.At the same time,some problems which should be further solved are exposed in the test process.