变径自锁复合固井胶塞的研制与应用

Development and Application of the Taper Self-locking Compound Cementing Plug

针对常规固井胶塞不能满足套管滑套工具串内径多次变化的特殊需求,研制了适应114.3 mm(4in)套管滑套固井配套工具的变径自锁复合胶塞。胶塞大、小胶碗采用分体式结构设计,按"大-小-小-小-小-大"顺序排列,采用同轴不同径的胶碗结构实现对套管刮削,同时设计了卡钉装置,具有自锁功能。室内试验结果表明,胶塞可以顺利通过模拟滑套短节,且无明显磨损,大、小胶碗未发生重叠与干涉。套管滑套固井胶塞现场试验13井次,试验成功率100%,说明该胶塞能满足套管滑套固井、完井现场施工需求。

The conventional cementing rubber plug cannot satisfy the special requirement of the changes con- cerning the inner diameter of casing sliding sleeve＇ s tool string. Therefore, the Research Institute of Oil and Gas Technology of Changqing Oilfield developed the taper self-locking compound plug which is suitable for the matching tool of the ~114. 3 mm casing sleeve. The big and small rubber cups of the plug adopted a split body design, ar- ranged in the sequence of ＂big-small-small-small-small-big＂ cups. The cup structure with the same axis and differ- ent diameters was adopted to achieve casing scraping and cutting. Meanwhile, the clamp device was designed with the function of self-locking. The laboratory test shows that the plug can go smoothly through the simulation sleeve joint. There is no remarkable abrasion and no overlapping and interference with big and small cups. The field test of the plug was carried out 13 well-times with a 100% experimental success rate. It can satisfy the requirement of cas- ing sleeve cementing and well completion operation.