A stepless drag fracturing process in casing and fracturing tool string

Abstract

The invention relates to a casing differential-free dragging fracturing technology and a fracturing tool string and belongs to the field of oil-well underground operation. According to the invention, the steps of positioning in well, sealing, jetting holes, fracturing, circularly backwashing and unsealing pipe columns are adopted for performing multistage staged fracturing on unconventional hydrocarbon reservoirs, such as tight gas reservoirs and shale gas reservoirs, so that the problems that the present multistage staged fracturing technology is complex in process, a compression packer is drilled after the fracturing operation is completed, the process consumes long time, the cost is high and the stratum is easily polluted can be solved. The casing differential-free dragging fracturing technology can effectively reduce the construction energy consumption, has the advantages of no differential limitation, no limitation to fracturing layer interval, no requirement for drilling and shorter construction time and has positive popularizing significance in performing multistage staged fracturing on the unconventional hydrocarbon reservoirs, such as tight gas reservoirs and shale gas reservoirs.

Description

technical field [0001] The invention relates to a stepless fracturing process in a casing and a fracturing tool string, belonging to the field of downhole operations of oil and gas wells. Background technique [0002] As my country gradually implements exploration and development of unconventional oil and gas reservoirs such as tight gas reservoirs and shale gas reservoirs, the fracturing stimulation process is also gradually showing the trend of large-scale, multi-stage and staged fracturing. However, in the implementation process of the existing multi-stage segmental fracturing stimulation process, after the pipe string is run in and the packer is set in place, it is necessary to lift the pipe string to remove the connecting piece, and then run the sealing tie-back intubation again. The fracturing operation makes the process complicated; and after the fracturing operation is completed, the compression packer needs to be milled and drilled. This process is not only time-con...

AI Technical Summary

Problems solved by technology

However, in the implementation process of the existing multi-stage segmental fracturing stimulation process, after the pipe string is run in and the packer is set in place, it is necessary to lift the pipe string to remove the connecting piece, and then run the sealing tie-back intubation again. The fracturing operation makes the process complicated; and after the fracturing operation is completed, the compression packer needs to be milled and drilled. This process is not only time-consuming and costly, but also easily pollutes the formation

Images