反循环砾石充填防砂工艺的改进及应用

针对套变井、侧钻井、变壁厚等特殊井身结构井出砂，导致油井不能正常生产的矛盾，研究了一种反循环砾石充填防砂工艺来解决这一矛盾。2001年10月-2003年7月该工艺在东辛油田的侧钻、变壁厚等特殊井身结构井现场先导性试验应用3口井，实施后一次成功率100％，有效率100％，平均单井日增油3．8t，累计增油5871．Ot，取得了较好的效果。实践证明：该工艺为解决东辛油田的侧钻、变壁厚等特殊井身结构井的防砂，挖潜增效提供了一种新的途径。

Improvement of reverse circulation gravel pack for sand control and its application in wells with special structure

Sand production in special well structure such as casing changing well, sidetracked well, and thickness changing well can induce production problems in oil well. A reverse circulation gravel pack sand exclusion technique to solve this problem has been studied in this paper. The technique was applied in the pilot test in three sidetracked and thickness changing wells of Dongxin oilfield from October 2001 to July 2003. The one-off success ratio was 100% , and the available ratio was 100% . Initial daily fluids production was 49. 8m3 , and daily oil production was 11. 5t. Average single well daily production increment was 3. 8t, with a comprehensive water cut of 80.5% and accumulative oil increment of 5871. 0t. The practice has proved that this technique has provided a new way and idea to solve the problem of sand exclusion and production enhancement in special well structure such as sidetrack and thickness changing in Dongxin oilfield.