Research And Evaluation On Eccentric Wear Prevention Technology For High Water Cut Wells With Oil Lubrication

The stage of development oil has entered medium or later terms,the water content of output liquid had a sharply rise,the output liquid phase gradually translated from water-in-oil into oil-in-water,the lubricant between the rods and pipes translated from crude oil into high salinity water.Due to the high salinity containing of production fluids in high water wells,the metal surface of the sucker rods and the tubes would come up the electrochemical reactions,leading to chafing and corrosion between rods and tubes more serious,thus caused the oil production cycles had been cut short,the cost of production had a substantial increase.Aim to the problem of corrosion and friction of high water-cut period,this thesis proposes the oil lubrication technology,it changed the traditional anti-eccentric technology which make rods and tubes contact directly,applied a hollow rod as fluid flow channel,the space was filled with crude oil or other lubrication medium appeared from self-split or wellhead injection,formed a lubrication environment between tube and rod annulus filled with lubricating medium,while supporting the development of wellhead sealing system,developed the oil lubrication anti-eccentric technology.Through the use of FLUENT software this thesis simulated the flow state of oil-water mixture drainage part,analyze the fluid flow of oil and water distribution process,determine the relationship between oil well production and the filling time of annulus,and the diagram fitting analysis,deduced the calculation formula for oil-water separation factor and the filling time of annulus.In addition,According to the research and optimization of the output liquid flowing analysis,mechanical analysis of the rods and tubes.According to researching of the oil lubrication anti-eccentric technology,the lubricating medium optimization,the improvement of the matching machines such as centralizer and sand prevention,solving the problem of corrosion exacerbating abrasion.Besides,this thesis conducted laboratory tests and implementation in the construction site,to make sure the maximization of the technology application effect.We selected 11 high water cut wells in Shengli oil filed to conduct this technology and obtained an ideal result.