捞砂工艺在煤层气定向井中的应用

摘要

冲砂存在漏失、污染煤层的问题，煤层气井井筒清砂作业，主要依靠捞砂工艺。但捞砂在定向井的施工比直井的成功率要低。分析捞砂工艺的特点和难点，找出在煤层气斜井捞砂施工中捞砂有进尺却无效果的原因，是上提管柱过程中，捞砂铲的固定凡尔关闭不严，造成砂子漏失。通过使用双固定凡尔，有效地解决砂子的漏失问题，并在后期的生产中取得了很好的效果，提高了定向井捞砂施工的效率。%Since sand washing can easily arouse the problems of sand leakage and coal beds contamination, the most reliable meth-od for sand removal in CBM wells is sand bailing technique. Compared to sand bailing operation in vertical wells, those in direction-al wells face more challenges. Based on the summarization and analysis of the characteristics and difficulties of sand bailing tech-nique, this paper found out the reason that the noncommercial footage of sand bailing in the inclined CBM wells was due to tight-ness failure of the fixed valve in the bailer conductor contributed to the leakage of sand during the process of the column raising. The application of double fixed valve can well solve the problems of sand leakage,obtained good effects during the later production period and highly increased sand bailing operation efficiency in directional wells.