Research And Application Of Radial Jet Drilling Technology In Offshore Oilfield

Offshore oilfields are limited by working space.Traditional means of increasing production,such as fracturing,can only be carried out through special fracturing vessels.The risks are high,the cost of single well operation is high,and the economic benefits are poor.Radial jet drilling technology utilizes the hydraulic rock breaking effect of high-pressure water jet,which can increase the seepage area and drainage radius of the original wellbore,and achieve the purpose of increasing production and increasing injection.Casing opening is the key to achieving radial jet flow in coiled tubing,this technology has applications in several domestic oilfield,but limited to drift,bottom hole temperature and pressure,casing mate rial and other factors,complex hole casing opening has been very low success rate.And current technology cannot determine whether hole drilled through casing successsfully at the scene.For the particularity of offshore oil fields and oil wells.This paper is based on study of radial jet hole technology in complex well,research and development tools and optimization design aimed at the drilling pressure control difficulty,low success rate of opening,opening success judgment difficult situation using existing technology,including:The drilling pressure controller is developed to control the drilling pressure,The finite element analysis tool is used to confirm the torque and the range of drilling pressure,The experimental platform is constructed to simulate the adaptive drilling test,so the operation ability and parameter design of tool string in different well condition are further implemented furthermore.Using Vx Spectra multiphase flow meter and PRODcast Vx software monitoring system trac-king drilling,can confirm drilling in real time.The ground experiment shows that the improved process can be shortened from 40-45 minutes of the original technology to 4-10 minutes,and the success rate of opening hole is 100%.The process was successfully tested in the Z50-12 well with a large skin factor,by using radial jet measures,the connectivity between the reservoir and wellbore conditions improved,water injection effect is good,300%augmented injection,injection pressure dropped by 45%.