水平井套管定位球座分段多簇压裂技术

Multi-cluster Staged Fracturing Technology of Horizontal Well with Casing Ball Seat

赵振峰 唐梅荣 杜现飞 安杰 马兵 徐创朝

ZHAO Zhenfeng TANG Meirong DU Xianfei AN Jie MA Bing XU Chuangzhao

中国石油长庆油田分公司油气工艺研究院

Oil & Gas Technology Research Institute, PetroChina Changqing Oilfield Company, Xi'an 710021, Shaanxi, China

水平井体积压裂是国内外开发致密油气藏的核心技术，目前主流的泵送桥塞多段压裂工艺、水力喷砂多段压裂工艺、裸眼封隔器压裂工艺由于受排量、钻塞、全通径等限制，均不能满足水平井低成本、高效体积压裂的技术需求，而且随着水平段长度增加，这种技术局限性愈加明显。为此，提出了水平井套管球座分段压裂技术。其技术原理是：在套管上预置工作筒固井完井，压裂时泵送专门的射孔投放联作工具到预定位置，将弹性球座投放至套管预置工作筒完成配接，然后上提联作工具进行多簇射孔，最后将可溶球投至弹性球座上，封隔下层，进行光套管分段多簇压裂。研制了套管预置工作筒、弹性球座、可溶球等关键工具，对施工工艺参数进行了优化，并进行矿场试验，实现了在长水平段多簇射孔联作一体化、大排量压裂、压后免钻快速投产、井筒大通径的体积压裂技术目标。现场试验6口井，成功率100%，其中水平段最长1 525 m，试油周期缩短30%以上，作业成本降低10%以上，单井产量提高20%以上，提效降本效果明显，具有较好的推广应用前景。

Horizontal well SRV (Stimulation Reservoir Volume) is the core technology to develop tight oil and gas reservoirs at home and abroad. At present, the main technologies include multi-stage fracturing technology with pumping bridge plug, multi-stage fracturing technology with hydraulic jet and fracturing technology with open hole packer, but they cannot satisfy the technical requirements on low cost and efficient SRV of horizontal wells due to the limitation of displacement rate, drilling plug and full bore. And this limitation will be more and more serious with the increase of horizontal section length. In this paper, therefore, the horizontal-well staged fracturing technology with casing ball seat was proposed. Its technical principle is as follows. Firstly, preset the working barrel on the casing for well cementing and completion, pump the dedicated perforation-releasing combination tool to the preset location during the fracturing, release the elastic ball seat to the preset working barrel on the casing and connect it. Secondly, lift up the combination tool and carry out multi-cluster perforation. Finally, release the soluble ball to the elastic ball seat to isolate the lower layer and carry out multi-cluster staged fracturing with bare casing. The key tools were developed, including the preset working barrel, the elastic ball seat and the soluble ball, and the construction technological parameters were optimized and tested on site. Thus, the SRV technical targets were realized, including integrated multi-cluster perforation combination of long horizontal section, high-rate fracturing, drilling free and fast commissioning after fracturing and large bore. It was tested in 6 wells and the success ratio is 100%. Among these 6 wells, the longest horizontal section is 1 525 m long. The effect of efficiency increase and cost reduction is remarkable with production test period shortening by more than 30%, operation cost reducing by more than 10% and single-well production rate increasing by more than 20%. It is promising in popularization and application.

10.13639/j.odpt.2018.03.018