论文部分内容阅读
微间隙产生的原因及大小水泥环和套管或地层间的界面上的微间隙是水泥胶结缺陷中最常见的一种。微间隙产生的原因,除了水泥和套管、岩石的热膨胀系数不同外,还由于固井工艺不完善;固井水泥中有杂质,固井过程中套管下沉或旋转;产生微间隙的原因还可能是井下作业时,井下工具和套管的碰撞、射孔密度过大。此外,地层水,特别是含硫化氢的地层水的腐蚀作用,也会产生微间隙。实验室研究表明,微间隙一般是环状的,
The reason and size of the micro-gap The micro-gap at the interface between the cement sheath and casing or formation is the most common type of cement cementation defect. The cause of the micro-gap is different from the thermal expansion coefficient of the cement and the casing and the rock, but also due to the imperfect cementing technology, the impurities in the cementing cement, the casing sinking or rotating during the cementing process, and the reason for the micro-gap It may also be downhole operations, the collision of downhole tools and casing, perforation density is too large. In addition, the formation of water, especially hydrogen sulfide formation water corrosion, will also have micro-gap. Laboratory studies show that the micro-gap is generally ring-shaped,