Smaller shaped charges with a 34 to 43-mm, 18-to-21-gram Copper-Lead liner (Tungsten added for "Deep Penetrators"), engineered for 318 -in OD guns, targeting US Land shale, can produce, an average, a lateral entry of 0.36-inches. A larger diameter entry-hole (EHD), based on perforation design (limited entry vs. high perf. design) has several benefits: lowering of "Perforation Friction" (Pf), lowering of treatment pressures, larger flow across each perforation, fewer chances of a screen-out, uniform drainage, and engineered completions where larger EHD perforations can be placed at the "Toe" with decreasing EHD perforations towards the "Heel" to offset wellbore fluid friction, especially in 3-mile long lateral "Toe". Such was the motivation behind engineering a water reactive, degradable-liner from High-Entropy-Alloys (HEA), producing a significantly larger entry-hole and accompanying debris-free perf-tunnel from a smaller charge, without changing the liner geometry or size, such that it can be universally accommodated in smaller diameter API gun, for example with a 318-in OD.
A step change in adding sensing and intelligence to a shaped charge, enabling remote monitoring of zonal performance through strategic deployment of the product, was envisioned for the very first time, adding smart nano-particulates as unique identifiers or tracers in the composite liner bulk. As these novel charges are fired, the thermally stable, doped, nanoparticle rare earth oxide (REO) tracers are carried by the jet and deposited in the perforation tunnel. Hypothesized was their control release during flowback, being conveyed back to the surface with production. These nanoparticle tracers can be identified when they pass through an in-line detector with a collimated light source of predetermined wavelengths, illuminating the tracers, emitting photons with a unique fingerprint, thus identifying the nanocrystal. The detector, comprising a remote computing system configured to store and relay information relating to these tracers is under development. This industry first is a paradigm shift in remote-monitoring, alerting any end user, anywhere in the world, of selected downhole event triggers, without running any device in the well. Never before envisioned innovation to identify non-productive zones, diverter effectiveness, water break out and much more can now be determined, effectively and economically.
A five-well field trial of tracer shaped charges with degradable liners were undertaken in the Permian shale (US Land), shot in parallel to industry premium charges, every other stage for selected stages, for a comparative performance analysis. Generally observed were: Up to (a) 10% less time to design rate (b) lowering of pad volumes (ESG) (c) distinct reduction in perf-friction (d) Successful tracer conveyance via charges and returns with flowback fluids to surface. Given its superior performance, far exceeding initial field introduction metrics, tracer charges with degradable HEA liners are predicted to be a game changer in harnessing formations with high frac-gradient and tight rocks, including carbonates in Middle East and North Africa (MENA).
