多段分层注水井逐级解封封隔器研制与应用

DEVELOPMENT AND APPLICATION OF THE STEP-BY-STEP RELEASABLE PACKER IN THE STAGED LAYERED WATER INJECTOR

常用压缩式封隔器的技术结构普遍是坐封时用解封销钉来锁住整个坐封机构,保持胶筒压缩,解封时通过剪断这个销钉实现胶筒的释放。如果解封销钉小一些,注水过程中外压升高时,销钉常常会自动剪断使封隔器解封;如果加大销钉,每一级封隔器解封力增大,导致管柱上提力逐渐增加,致使解封困难。针对这个问题,通过改变封隔器的技术结构,使坐封机构和解封机构脱离,研究设计了能实现逐级解封的注水井可洗井封隔器,从而改变了常规水井封隔器管柱上提整体管柱、封隔器胶筒同时摩擦套管壁的概念,每级封隔器单独承受上提管柱的解封力,从最上一级封隔器开始依次解封。现场应用表明,逐级解封封隔器实现了管柱在封隔器逐级解封的情况下小载荷起出,从而有效地解决了管柱无法顺利起出的问题,为多层段细分注水提供了技术保障。

The technical structure of the commonly used compression-type packer generally refers to the whole-sealed one locked by the releasing pin when set so as to ensure the rubber cylinder compressed and released by the pin when releasing the plugging. If the pin is a bit smaller,when the pressure is risen in the course of the water injection,the pin is often automatically cut and cause the packer released; if the pin is a bit bigger,the releasing force will be increased for each step of packer,this condition will result in the gradual power rise of the string pulled out,thus the release will be rather difficult. In the light of the following problem,by changing the technical structures of the packer and making the setting and releasing mechanisms separate,the washable water-injector packer has been developed and designed to realize the progressive release,and the concept has been changed for the simultaneous friction of the casing wall when the whole string and rubber cylinder pulling upwards for the conventional water-well packer string,each step of the packer can individually stand the releasing power of the pulled string,and finally the release can be realized step by step from the top packer. The field application shows that the step-by-step packer has realized the small-load string pulling under the condition of the step-by-step release of the packer,therefore the problem of having no way to smooth pull the string has been effectively solved. All the a-chievements have provided the technical guarantee for the multi-interval subdivided water injection.