1.The sectional hydraulic fracturing is classified into drag-type sectional hydraulic fracturing and ball-sitting hydraulic fracturing;

2.By virtue of the advantages of directional drilling technology, this process achieves precise fracturing, large fracturing scope safety and reliability in the target area, which is mainly used for penetration extraction and roof weakening of coal seam. It can reduce the drilling load of gas extraction, shorten the extraction cycle, and realize large-area enhanced extraction.