In view of the difficulties during workover treatments in Jidong Oilfield, such as circulation loss, slow water cut recovering, serious formation damage, a novel technique named Fuzzy-Ball was applied based on the temporary blocking mechanism analysis of Fuzzy-Ball workover fluids. The Fuzzy-Ball can self-match leak passages completely during workover, and then flow back automatically from formation. Laboratory evaluation showed that the workover fluids could be stable for more than IS days, enhance formation pressure bearing capacity, up to 7 Mpa, and invade formation less than 8 cm. What is more, the core permeability can recover up to 90%. Well L12-6 and NP23-X24091 are two examples for the application effects. The water cut of well L12-6 recovered only in 3 days, oil productivity increased more than 3 tons per day and water cut reduced by 30% after the pump inspection by Fuzzy-Ball workover fluid. For well NP23-X24091, formation bearing pressure capacity was enhanced up to 6~7.5 Mpa after the fuzzy-ball workover fluid blocking formation and squeezing cement, oil productivity increased more than 10 tons per day, and water cut reduced by 5%. The indoor and onsite experiments proved that the Fuzzy-Ball workover fluid had good effect of blocking and less damage to formations.%针对冀东油田在修井过程中出现漏失、含水恢复时问长、储层伤害严重等问题,在分析了绒囊暂堵机理的基础上,现场采用绒囊修井液体系,利用绒囊自匹配漏失通道实现全面封堵并可自动返排的特性解决了这一难题.室内评价表明,绒囊修井液体系稳定时间15d以上,封堵地层后可提高地层承压能力达到7 MPa,修井液侵入地层在8cm以内,岩心渗透率恢复值达90％以上.在L12-6井和NP23-X2409井进行了现场应用,L12-6井采用绒囊修井液暂堵检泵,含水恢复至正常水平仅需3d,且日产油增加3t多,含水率下降了30％；NP23-X2409井采用绒囊修井液暂堵后挤水泥,承压能力提高了6～7.5 MPa,日产油增加了10t多,含水率下降了5％.室内和现场应用表明,绒囊修井液封堵效果好,对储层伤害较小.
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