Hydraulic fracturing [fracking] is the propagation of fractures in a rock layer from the action of a pressurized fluid. Many fractures form naturally, called veins or dikes, and can create conduits which gas and petroleum use to migrate to reservoir rocks. Fraccing or fracking, is a technique used to release petroleum, natural gas (including shale gas, tight gas and coal seam gas). This type of fracturing creates fractures from a wellbore drilled into reservoir rock formations.
During the fracking process, a mixture of water, sand and other chemical additives is pumped under high pressure into the shale formation to create small fractures. A chemical additive, designed to protect the integrity of the geological formation, is mixed with approximately 99.5% water and sand. The resulting fractures are “propped” open by the sand, which allows the natural gas to flow into the wellbore where it is collected at the surface.
The frac ball is an integral part of the process. During the fraccing stage, straight water is injected into a well, the frac balls act as a temporary plug to divert water away from it so that all areas of the zone that is being fracked will be done equally. The frac ball needs to be able to withstand extreme pressures. At the completion of each fracturing stage, the next larger frac-ball is injected into the well, which opens the next sleeve, and so on, until all of the sleeves are opened and multiple fractures are created in the well.