江苏油田堵漏试验评价技术研究

Study on Loss circulation control test instrument in Jiangsu Oil Field

现有的堵漏试验仪器基本原理相似,关键在于模拟漏失层的介质不同。研制了DL-1和DL-2两套堵漏试验仪器,DL-1使用砂床填充模型,DL-2使用人造岩心。人造岩心是在分析江苏油田漏失层特性的基础上,利用混凝土离心浇注法制得的,其尺寸大,孔隙度和孔径分布可以人为控制。利用DL-1和DL-2两套仪器以及人造漏失岩心,可以较为真实地模拟井下漏失情况,直接观测堵漏效果。得出,弹性、刚性和纤维类材料合理搭配且粒径分布合理的复合堵漏剂,可迅速有效封堵孔隙性、裂缝性漏失层。

The mud loss testers available now have same basic working principle,with differences in the media simulating lost circulation zones.Two mud loss testers,DL-1 and DL-2,were developed.DL-1 uses sand bed whereas the DL-2 adopts artificial cores.The artificial cores are made based on the analyses of the reservoir physical properties in Jiangsu oilfield,and their sizes are relatively big and the porosity and pore sizes can be adjusted,according to special requirements.Using DL-1 and DL-2,Downhole mud losses can be simulated in laboratory with reasonable accuracy.Experiments on these two devices showed that elastic,rigid and fibrous material should be used in specially designed size distribution to seal off the thief zones quickly and efficiently.