苏里格致密砂岩储层小井眼压裂技术

Slim-hole fracturing technology for tight sandstone reservoirs in Sulige

苏里格致密砂岩储层低孔、低渗、低压、低产、多层比例高、非均质性强,常规小井眼压裂工艺成本高,工序繁琐,压裂效果不及预期。对比四种小井眼压裂改造工艺特点,优选小尺寸封隔器分层压裂和可溶桥塞+射孔联作套管压裂两种适合苏里格气田小井眼压裂改造工艺技术。通过改进封隔器尺寸和胶筒的长度,更换水力锚的密封胶圈,研制可溶桥塞等,完善了小井眼压裂工艺技术。经现场施工30口井,其中采用小尺寸封隔器分层压裂17口,采用可溶桥塞+射孔联作套管压裂13口,施工成功率100%,与邻井相比平均无阻流量分别提升52.31%和92.14%。该技术为下步致密砂岩储层有效开发奠定了基础,具有推广价值。

The tight sandstone reservoir in Sulige is characterized by low porosity,low permeability,low pressure,low production,high multi-layer proportion,and strong heterogeneity.Conventional slim-hole fracturing processes are costly,cumbersome,and often fail to achieve expected results.After comparing four different slim-hole fracturing processes,two suitable processes suitable for the Sulige gas field were selected:staged fracturing with small-size packer and soluble bridge plug+perforated casing fracturing.The slim-hole fracturing process was improved by improving the size of the packer and the length of the rubber tube,replacing the sealing rubber ring of the hydraulic anchor,and developing a soluble bridge plug.The processes were applied to 30 wells on site,with 17 wells using staged fracturing with small-size packer and 13 wells using soluble bridge plug+perforated casing fracturing.The construction success rate is 100%,and the average open flow rate is increased by 52.31%and 92.14%respectively compared with adjacent wells.This technology has laid the foundation for the effective development of tight sandstone reservoirs and holds significant value for promotion in the future.