PURE Perforating for Ultimate Reservoir Exploitation system optimizes the well dynamic underbalance—the transient underbalance just after creation of the perforation cavity. The software specifies a unique perforating system and optimum completion process. This controls the optimum dynamic underbalance rather than relying on the estimated reservoir pressure. This technique has been successfully performed in hard- and soft-rock formations, oil and gas reservoirs, and sandstones and carbonates.
An Alaskan water injection well was performing below expectations. The 90 ft of perforations were taking 17,500 B/D. Analysis of the well and reservoir conditions by PURE design software resulted in a job design using 3 3/8-in. guns and PowerJet deep penetrating shaped charges.Although only a 20-ft section was perforated, the injection rate increased to 25,000 B/D. The injection pressure remained approximately the same or slightly lower. The injection profile shows clearly the PURE perforations were taking 93% of the total flow for an improvement of 493% in the contribution rate.Two low-permeability (1-mD) gas wells in the Weber formation of Wyoming were perforated with PURE technology at initial overbalances of 3000 and 3700 psi. Both wells flowed naturally at 5.5 and 3.8 MMscf/D, respectively, without the acid stimulation usually needed to obtain clean perforations. The wells were tubing-conveyed perforating permanent completions.
TNK-BP saw a 250% increase in well production and minimized skin with the help of the PURE perforating system for clean perforations.