试油套卡处理方案初探

DISCUSSION ON CASING STICKING PROCESSING SCHEMES IN THE PROCESS OF WELL TESTING

在试油过程中经常会遇到不同的井下复杂情况,套管内卡钻现象就是其中之一。DST作业时油套环空有沉砂或落物、地层出砂等易发生卡钻现象,其危险性远大于钻井过程中发生的卡钻事故。出现这种套卡后,首先要分析清楚井下具体情况,查找出卡钻的真正原因所在,计算各种处理方案的所用时间、费用和风险成功率。然后采用最佳的方法进行处理。青海油田柴达木盆地西部沟6井就在试油过程中发生了类似事故,事故发生后对该井进行了打捞倒扣作业,对事故发生原因、处理方案进行了探讨,终因在修井作业中发现套管破裂,被迫放弃。

The downhole complex problem often occurs in the process of well testing such as pipe sticking in the casing. It occurs incidentally in DST process if there is sand production or there is sand or fish in the annular of production casing. It is far more dangerous than the pipe sticking in the drilling process. When this trouble occurs, we should analyze the details of the down hole, find the real reason of the pipe sticking, and calculate the time, cost and the possibility of success for various processing schemes. Then adopting the optimal method deals the sticking in the casing. The similar trouble occurred in the process of well testing of Gou 6 in the western Caidamu Basin. Fishing and back-off operation were done when the trouble occurred. It is forced to give up because it is found that the casing is failure in the process of well repairing. The reason for trouble and the dealing scheme have also been discussed in this paper.