迪那2 气田测射联作完井工艺评价与优化

迪那2 气田产能建设早期普遍采用测射联作完井工艺, 为气田快速上产提供了重要支撑, 但投产后也逐渐 暴露出井筒堵塞、井下动态监测受限等问题。经统计, 测射联作完井的生产井75%出现油压急剧波动下降的异常现象, 结合气藏工程理论及修井实践综合分析认为, 油压异常的根本原因在于堵漏剂返排、地层出砂等堵塞了测射联作管柱的 生产筛管(即打孔油管)。为此, 产能建设中后期采用射孔、测试分步实施的完井工艺, 显著减少了井筒堵塞的现象, 并为井底压力测试及生产测井的开展创造了有利条件。该研究为类似气井采用射孔、求产完井工艺提供了借鉴。

Evaluation and Optimization of Completion Technology with IntegratedPerforation and Testing in Dina 2 Gasfield

DST/ TCP (drillstem test/ tubing-conveyed perforating) completion technology was generally applied to the early stage productivity construction in Dina 2 gas field, and this provided an important technical support for the rapid rise of production rate of this gas field. After putting into production in commission, some problems gradually exposed, such as wellbore blockage and limited downhole performance monitoring. By our investigation and statistics, the sharp undulate decline of the tubing pressure appears in 75% producers that were completed with the DST/ TCP technology. With combination of gas reservoir engineering theory and well workover practice, the fundamental reason for anomaly of tubing pressure is that the plugging agent flows back and sand production in the formation, and they clogged the production screen (i.e. the perforated tubing) of the DST/ TCP tubing strings. Accordingly, an well completion technology was adopted during the later period of productivity construction that the perforating and drillstem test were carried out individually which observably reduced the wellbore blockage, and provide favorable conditions for bottom hole pressure test and production logging. This study provides a reference for the use of perforation, gas production and completion in similar gas wells.