异常高压储层水力喷砂射孔多层压裂投产技术

Commissioning technology of hydraulic abrasive perforating and multi-layer fracturing in abnormal high-pressure reservoirs

哈萨克斯坦肯基亚克油田盐下二叠系砂岩油藏压力系数超过1.7,采用常规射孔后压裂工艺或者适用于常压储层的不动管柱喷砂射孔压裂工艺,存在井控风险大、转层作业周期长、改造不彻底等技术难题。为提高单井产能,在单层水力喷射加砂压裂技术获得显著增产效果后,研发出逐级坐封封隔器和带滑套喷枪,通过理论参数计算,实现了工艺优化与入井管柱的组配,形成异常高压储层水力喷砂射孔多层压裂投产技术。在现场完成了3口井不动管柱逐级坐封单井分两层喷砂射孔加砂压裂工艺的现场试验,成功率100%。措施后平均单井日增油52.3 t;现场施工数据显示,转层后两层水力喷砂射孔时的射孔压力差小于2 MPa,验证了该工艺在理论上满足3层以上的压裂改造。该工艺实现了不压井条件下多套储层的射孔、压裂改造及投产一体化作业,对高压油气井储层改造具有推广意义。

The pressure coefficient of the subsalt Permian sandstone reservoir in the Kenkiyak Oilfield in Kazakhstan exceeds 1.7.There exist some technical problems,such as high well control risk,long operation period when replacing layers,and incomplete stimulation,if adopting conventional post-perforation fracturing process or hydraulic abrasive perforation fracturing process with fixed string suitable for normal pressure reservoirs.In order to increase single-well productivity,after achieving a significant increase in production of a single layer with hydraulic abrasive fracturing technology,the step-by-step setting packer and the spray gun with a sliding sleeve have been developed.Through the calculation of theoretical parameters,the matching between process optimization and well pipe string has been realized,forming the commissioning technology of hydraulic abrasive perforating and multi-layer fracturing in abnormal high-pressure reservoirs.The field test of three wells using hydraulic abrasive fracturing technology in two layers for each well with step-by-step setting fixed pipe string was completed,with a success rate of 100%.After the stimulation,the average oil production rate increases for a single well is 52.3 t.The field operation data shows that the perforating pressure difference of the two layers after the layer replacement is less than 2 MPa during the hydraulic abrasive perforating,which verifies that the process can theoretically meet the fracturing stimulation of more than 3 layers.This technology realizes the integrated operation of perforating,fracturing and commissioning of multiple reservoirs without killing wells,and has popularization significance for reservoir stimulation with high-pressure oil and gas wells.