双向三力加载注气封隔器的研制

Two-way Three-force Loading Packer for Gas Injection

针对国内CO_2驱油田注气井普遍存在带套压生产的情况,研制了双向三力加载注气封隔器。新型封隔器采用双液缸结构,胶筒受到双向液压力和外加载荷的充分压缩,在轴向上与套管的接触应力分布更为均匀,大幅度提高了胶筒的密封效果;通过增设胀紧机构,补偿了液压力消失后锁环的回退和持续压缩胶筒产生的微量坐封距,解决了注气封隔器承下压能力不足的问题,从结构上确保了封隔器的密封长效。双向三力加载注气封隔器在CO_2驱油田进行了现场应用,最高注气压力28 MPa,全部实现了无套压生产。该产品的研制成功满足了注气技术对封隔器气密性的要求。

To deal with the gas injection wells operation with casing pressure in the most C02 flooding field in China, a two-way three-force loading packer for gas injection has been developed. The novel packer adopts the dual-cylinder structure, so that the rubber is fully compressed by the bidirectional hydraulic pressure and the external load, and thus the contact stress in the axial direction is more evenly distributed, which greatly improves the sealing effect of the rubber. The added expansion mechanism compensates the retreat of the locking ring after the hydraulic pressure disappears and the micro setting distance produced by continuous compression of the rubber, thus addressing the issue of insufficient pressure bearing capacity of the packer for gas injection, ensuring the long-termseal performance of the packer. The new packer was successfully applied in the field of C02 flooding oilfield with the maximum injection pressure of 28 MPa, achieving gas injection with zero casing pressure. The successful development of the product has met the gas injection technology requirements for theair tightness of packer.