延迟膨胀颗粒堵漏剂的研究与应用

井漏是严重影响钻井生产正常进行的井下复杂情况之一，目前所采用的堵漏方法主要是桥塞堵漏和快干水泥堵漏，桥塞堵漏所采用的材料多由天然物质加工而成，它们的吸水膨胀能力较小或不具备吸水膨胀能力，在钻井堵漏时，往往易造成堵漏效果不佳和堵漏后发生重复性漏失。延迟膨胀颗粒堵漏剂WEA-1是一种吸水膨胀性很强的树脂，具有延迟膨胀的特征，因此能够保证颗粒材料有足够的时间进入井下漏失层位后继续膨胀，其吸水膨胀体积倍数可以达到4～8倍，同时，WEA-1的机械弹性形变能力强，拉伸强度大，封堵强度高，与各种水基钻井液配伍性好，能够达到良好的堵漏效果和有效提高地层承压能力的目的。延迟膨胀颗粒堵漏剂在彩南油田的C2872井、C3002井和霍001井进行了应用，堵漏均很成功，用WEA-1堵漏浆堵漏后，循环钻井液均再未发生漏失。

Study and Application of Granular Postponed-Swelling LCM

This paper evaluated as an introduction the deficiencies of the commonly used lost circulation curing methods at present-plugging with LCM and quick setting cement squeezing that they may fall in failure or the seal does not persist so long as required and then described in detail a granular water absorbing postponed-swelling lost circulation curing agent WEA-1.This material is resin with strong water absorbing ability and postponed-swelling effect that assure the granules of it has enough time to get into the lost circulation zone and then expand their volume 4~8 times after absorbing water.The seal in the lost circulation formation formed by these granules has good mechanic-elastic deforming character,enhanced tension strength and satisfied compatibility with varied drilling fluid additives therefore it can provide an excellent loss circulation curing effect and raised pressure resistance of the thief zone.WEA-1 was successfully used in well C2872,C3002 and Huo-001 and lost circulation has never been encountered again in the cure zones till the well completion.