RESEARCHES AND OILFIELD APPLICATIONS OF OIL WELL MASKING WASHING-WELL TECHNOLOGY

According to the situation that there is loss of circulation,formation damage and water out in washing-well of negative pressure oil well,the viewpoint of masking washing-well technology is proposed,and relevant washing fluid is prepared.Library and oilfield experiment show the masking washing fluid have better stability of suspension、masking temporary shut-off、high temperature and salinity,and ability to remove temporary shut-off;All problems that oil-wellwater removal time is long,formation is damage,and producing capability decreases are resolved;Washing-well water is saved,the working program under well is simplified,non-production cost decrease;1%~5% recovery efficiency is attained in per well.