套损井小直径分层压裂技术

Small Diameter Layered Fracturing Technique for Casing Damaged Well

油水井受地层剪切发生套损后,套管内通径缩小,常规55 MPa压裂管柱无法压裂施工。为了实现该类套损井压裂措施增油,采用了2种小直径压裂工艺管柱,JX新型小直径和CY双封单卡压裂工艺管柱。通过分析,JX小直径压裂管柱能压裂5个层段,单级喷砂器最大过砂不大于36 m^(3),各层上下封隔器卡距可独立设计,基本不存在合层或弃层;CY双封单卡小直径压裂管柱全井砂量可达200 m^(3),对压裂层段数和单层加砂量均没有限制,但各层封隔器卡距需要统一,为控制投资有时需要层段合并或弃压。现场试验了8口井,压裂后日增油3.94 t,措施有效期内累计增油3 523.3 t,经济效益达742.36万元;2口欠注井液见到了良好的吸水恢复效果,截至目前累计增注6 510 m^(3)。两种工艺均能较好实现105 mm通径套损井压裂施工,满足现场需要,有推广应用价值。

After casing loss occurs in oil and water Wells under formation shearing,the inner diameter of casing decreases,and the conventional 55 MPa fracturing string cannot be fractured.Two kinds of small diameter fracturing strings,JX new small diameter fracturing strings and CY double seal and single clamp fracturing strings,were used to increase oil production in this kind of casing loss Wells.Through analysis,the JX small diameter fracturing string can fracture 5 intervals,the maximum sand excess of a single stage sandblast is no more than 36 m^(3),the clamping distance of the upper and lower packers can be designed independently,and there is basically no laminar or abandoned zone.The total well sand volume of the small diameter fracturing string with CY double seal and single clamp can reach 200 m^(3),and there is no restriction on the number of fracturing stages and the sand volume of single layer.However,the clamping distance of the packer in each layer needs to be unified.In order to control the investment,it is sometimes necessary to merge or abandon the pressure in the intervals.Field tests were carried out on 8 Wells.After fracturing,the daily oil increase was 3.94 t,and the accumulative oil increase was 3523.3 t in the effective period of the measures,and the economic benefit reached 7.4236 million yuan.The two under injection wells showed a good recovery effect of water absorption,with an accumulative injection of 6510 m^(3) up to now.Generally speaking,the two technologies can well realize the fracturing construction of 105 mm diameter casing loss well,meet the needs of the site,and have the value of promotion and application.