Abstract
This paper presents initial field results of a novel perforating technology for horizontal multistage unconventional wells. The gun system improves operational safety, efficiency and reliability with an ultracompact and simple plug-and-play design. The initial field results indicate that the enhanced casing holes distribution lower the required treating pressures because of lower tortuosity losses. The new gun system delivers better wireline and fracturing efficiency than conventional guns.
The design of the new perforating system is unique in that it has multiple perforating shaped charges placed in the same plane. This produces multiple perforations in planes normal to the well, reducing near-wellbore tortuosity and the associated pressure loss during pumping, uniform frac growth from every cluster, improved proppant placement, reduced screen outs, and improved productivity. Shaped charge entrance holes are uniform and sized to maximize uniform frac placement. The new perforating system is packaged in a compact design that has less than half the length and weight of a conventional gun system. This new ultrashort, ultralight gun reduces HSE risks with easier handling and less lubricator length required for rig up. Finally, the new system is fully disposable, and its new detonation system is simple to assemble and operate, which translates into significant improvements in safety and reliability.
The system brings multiple benefits over previous systems, and this paper highlights field trial results. This innovative perforating system has demonstrated a robust field performance adding significant value to multistage fracturing operations, reducing tortuosity and treating pressures, and realizing a step change in safety, efficiency and reliability.
Since the early days of horizontal wells in unconventional reservoirs, it has been known that many hydraulic fractures are required to maximize the economic potential of wells from very low permeability reservoirs. While this implies the use of multistage fracturing technology, this is only part of the solution. The use of limited entry perforating has been extensively used to create multiple fractures within each stage of a multistage completion, even when the fracture propagation pressure varies considerably from one cluster to another. By restricting the flow rate into a single cluster-fracture, it is possible to force fluid into all cluster-fractures, thus creating similar fracture lengths from all clusters, and therefore significantly increasing the stimulated volume and the total production of the well.
