SAGD Technology Research And Application Of Oil Well Operation

In recent years, SAGD production technology has been playing an increasingly important role in the exploitation of heavy oil in our country as an emerging technology. With the increasing of SAGD well groups, SAGD workover technology is becoming more and more mature. But under the influence of the SAGD well special wellhead and well structure, there are still many technical problems to be solved.(1) In dual operation of well control technology, most of the SAGD oil wells still use well control technology which is fit for vertical wells. In construction process, there are blowout of wellbore scrap and some other significant security risks because of the complex structure, the special tube in the well configuration, the high temperature of wellbore, the big pressure difference of bottom hole, the relatively backward facilities and well control technology in the ground well control,(2) As the big SAGD oil pressure difference and the frequent times of well killing before well workover, the SAGD well use well killing fluid in the reservoir with relatively high water salinity(more than 10g/L) and high temperature(higher than 70℃) condition in present. In this way, the stability is very poor and it severely affect the killing effect. There is very big harm to the reservoir, too.(3) A variety of complex geological conditions in the SAGD well for plugging construction will appear. If the leak proof agent used in the site is not good, it will not only affect the production efficiency, but also make the problem of subsequent workover construction can not be carried out etc.(4) The majority of workover operation of the SAGD well need manual work at this stage which require large of the workload of workers with low safety factor. Putting or getting sucker rod, tubing and downhole tool is a very heavy work which need the working personnel highly concentrate on it, with flexible and accurate action to complete requent operation. In this job, safe hidden trouble and big risk exsist so it is very easy to cause head injuries.In order to solve the above problems, the research work of oil well SAGD technology has been carried out, including the development of transport system, SAGD oil reservoir protection technology of SAGD oil well, high temperature anti leakage technology research, the SAGD oil well tube and rod mechanical and SAGD oil well blowout preventer pipe work. By using the SAGD technology, we can improve the well workover technical content, reduce the risk of well control operations, protect reservoir, ensure the effect of reducing pressure wells, reduce reservoir damage in workover process, prevent the occurrence of accidents in downhole operation, reduce the labor intensity of workers and avoid personal injury during the construction.