For the problem of co-existence of micron to millimeter-level loss channel in fractured-vuggy reservoirs,this paper suggested that good and fast crack plugging is the key to leakage control and reservoir protection.Drilling fluids dynamic damage evaluation experiments in zone 12 of Tahe Oilfield were conducted,the results indicated this drilling fluid could not meet the requirement of mud loss and formation damage control in fractured-vuggy reservoir. The drilling fluid was improved using temporary plugging theory. The temporary sealing rate of the modified drilling fluid reached 99. 999％ after 3 mins. The accumulated mud loss was less than 0. 5 mL after an hour. The ability was increased by 2. 3 times and the recovery rate was improved by 60％. All these indicate the temporary sealing is feasible. The temporary sealing has the characteristics of broad-range of particle size, fast bridging,compact sealing, moderate invasion, bi-directional pressure bearing and acid-removing etc. The differences between temporary sealing and temporarily shield sealing are mud loss formation, sealing form duration, press resistance,seal thickness,and filter cake removing methods.%针对裂缝-孔洞型储层从数十微来级至毫米级别漏失通道并存的储层漏失控制问题,提出漏失控制及储层保护的关键是又好又快地封堵裂缝.进行了塔河油田12区钻井液、完井液动态损害评价试验,结果表明,该钻井液、完井液难以满足裂缝-孔洞型储层的漏失控制及储层保护的需要.根据暂堵性堵漏思路改进了该钻井液、完井液,改进后约在3 min内形成暂堵率在99.999%以上的致密封堵层,且60 min累积滤失量不超过0.5 mL,较改进前裂缝封堵能力提高2.3倍,酸溶返排恢复率提高60%,证明暂堵性堵漏思路是可行的.暂堵性堵漏具有堵漏材料粒度范围大、架桥快速、封堵层致密、侵入适度、双向承压和酸溶解除等特点,暂堵性堵漏与屏蔽暂堵技术的差异主要体现在封堵对象、封堵层形成时间、封堵层承压能力、封堵层厚度、封堵层解除方法等方面.
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