大直径水泥密度测井评价方法及应用

Evaluation Methods and Application of Cement Density Logging in Large Diameter Wells

随着国内各地区对深层油气勘探开发力度的加大,大量采用外径在8in以上的套管进行中完固井,造成目前国内所常用的固井评价技术无法准确评价其固井质量。大直径水泥密度测井能够较好地解决大直径套管固井评价的问题。通过模拟对固定条件下不同水泥密度、不同套管壁厚与计数率比值的关系进行分析,建立了水泥密度和套管壁厚的响应关系,并制定了相应的评价方法。该方法应用于辽河油田的生产井、探井中,解释结论与固井情况相符。

With the increase of the exploration of deep-buried oil in all areas across the country,casings with outer diameters greater than 8inches were widely utilized for well cementation in a multiple-completed well,thus the commonly used well cementation evaluation technique could not correctly evaluate the cementation quality of large-diameter casings.While cement density logging in large diameter casing wells could solve the problem of evaluation cementing of large diameter casings.Simulation methods are used to analyze the relationship between cement densities,casing thicknesses,and counting rates under fixed conditions,the responding relationship between cement densities and casings thicknesses is established,and related evaluation method is developed.This method is applied in production wells and exploration wells in Liaohe Oilfield,and the interpretation conclusions are in consistent with that of cementation.