火驱井管外窜影响因素分析

External Casing Channeling Influencing Factors of Fireflooding Well

气窜是火烧油层驱油技术中面临的重要问题。受储层层内和平面非均质性影响,产出气体会沿高渗透条带突进,气体运移到固井质量差和套损的井时发生窜槽,窜出的气体既可能进入其他地层,又可能直接窜到地面,形成管外窜。根据资料调研和分析,管外窜一般由六方面原因引起,分别为:油藏因素、开发因素、井况因素、水泥环封隔失效、套管腐蚀或破坏和分层作业不当。

Gas channeling is an important issue in the fireflooding process. Affected by reservoir inner and planar heterogeneity,gas flowed along high permeable bands quickly. And channeling often appeared while gas moved by wells with poor cementing quality or casing damage. Sprang gases may enter other formations as well as directly went to the ground leading to external casing channeling。 External casing channeling was usually induced by reservoir factors,developing factors,well condition factors,cement sheath plugging,improper casing corrosion or damage and hierarchical operations.