In openhole horizontal wells in high-temperature, naturally fractured, deep formations, mechanical segmentation between stages for multistage fracturing operations is high-risk, costly, and sometimes ineffective. Acid fracturing using chemical diversion agents as an alternative to mechanical segmentation has been pilot-tested in some fields with satisfactory results, but the technique has not been studied experimentally or numerically extensively before now. This paper presents a newly designed triaxial fracturing system and describes a series of experiments that verified the validity of tool-free chemical diversion for multistage fracturing of openhole horizontal wells.
Introduction
Traditional staged fracturing technologies include double-pack single-slip multistage fracturing, packer/sliding-sleeve fracturing, and hydraulic-jetting multistage fracturing. These technologies use tools to achieve segmentation between stages.
