江苏地区井漏处理工艺

Mud Loss Control Technology in Jiangsu Area

在调查研究江苏油田多年来井漏井史资料的基础上,分析了引起井漏的原因及类型,提出应以单位时间单位面积的漏失量来衡量漏失的强弱,并应结合地区的地质特征、地层的压力梯度、漏层深度、漏失速度、漏失量等参数进行综合分析判断。根据江苏油田易发生井漏地区实际情况,研究了堵漏材料的性能要求及优选原则,制定了堵漏技术措施及施工要求注意事项。江苏地区SN区块的辉绿岩地层漏失一直是井漏预防和处理的难题,通过采用随钻堵漏工艺,结合憋压挤堵,合理调整堵漏剂配方,解决了这一问题。

Seeping losses and mud losses into fractures were frequently encountered in the Shanian,Weizhuang and Minqiao blocks in Jiangsu Oilfield,in which detrital rocks and igneous rocks were abundant.This paper discussed the determination of the types of mud losses,and pointed out that the severity of mud losses should be determined based on the amount of mud losses in a specified time period through a unit area.Different formulations of mud treated with lost circulation materials(LCM) and the techniques of using these LCM muds were described.Shown in this paper was the mud loss control techniques in Block SN,in which mud losses were much more frequently encountered in the past.Field practices showed that using mud loss control while drilling technology,combined with pressurized squeezing,and a modified sized LCM mud formulation,mud losses in Block SN can be successfully brought under control.Combination of LCM having different sizes,shapes and hardness can quickly seal off the fractured loss zones.The use of organic LCM in well depth less than 2,000 m was successful in stopping mud losses in fractured formations.