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Abstract ADNOC-offshore with their partners conceived and developed the concept of Dissolvable-Plugged-Nozzles (DPNs’), developing an inflow-control-device (ICD) with dissolvable elastomeric-plug to be installed on limited-entry perforated-liners in their extended-reach and deviated (ERD) injection-wells (Bachar et al. 2004, Beaman et al. 2016, Clews et al. 2018, Jackson et al. 2017, Kiyoumi et al. 2019, Mayer et al. 2014, and Sau et al. 2019). Benefits of DPNs’ encompass significant savings of the order of several- million-dollars for the client due to one or more of the benefits (a) Not having to pick-up a dedicated displacement work-string, thus significant time-savings of up to 5-days (b) Increase probability of running liner to TD through the ability to wash to bottom (c) Less fluid losses to the reservoir formation (d) Effective wellbore cleaning, among others (Roy et al. 2021, Roy et al. 2020, and Shamshy et al. 2023). With extended reach deviated island wells now reaching > 50,000 ft., often having a lateral length of > 30,000 ft., substantial resistance is encountered during deploying completions string to total depth (TD), necessitating jarring of the LEL assembly while running in hole (RIH), resulting in days of delay. Use of acidic breaker to reduce differential sticking necessitates qualifying a DPN wherein it retains mechanical integrity in breaker fluids for a minimum of 8 hours. This article encompasses underlying design methodology and includes verification and validation (V&V) testing results of multiple DPNs’ potted with low ROC partially vitrified high entropy alloy (HEA) plugs when exposed to 10.6 ppg brine and breaker. Objective of this qualification program was to identify the Breaker-Resist (BR)-DPN potted with the "specific plug chemistry", which reliably maintains mechanical integrity for extended time durations, 15 hours in buffered 10.6 ppg brine followed by 8-hours (+FOS) or more in 50/50 10.6 ppg brine/breaker. This was achieved with our HEA5 formulation. Validation success led to a greenlight by operator and approval for manufacturing needed number of BR-DPNs’ for field introduction, led by our commercialization partner, Baker Hughes. Our rigorous testing program has demonstrated promise of successfully establishing, including concept of a BR-DPN offering, patent pending "Dissolvable Plugged Nozzle Having Single or Multi-Layer Breaker-Resist Core", 63/658,864 dated 06-11-24 and granted Patent 11/719074 dated 08-08-23. In this study all evaluations have been conducted with un-inhibited aggressive 10.6 ppg brine and Breaker I. In the interest of time, per operator's advice we focused on testing and repeatably determined breakthrough times in available fluids. HEA5 formulation bought us a direct breakthrough time of 50 ± 10 hours in uninhibited 10.6 ppg brine. Operational tests in the aggressive 50/50 10.6 ppg brine/Breaker I bought >37 hours till breakthrough after 15 hours of exposure in uninhibited 10.6 ppg brine. They lasted 15+ hours in an earlier inhibited batch of 50/50 10.6 ppg brine/Breaker I after 15 hours of exposure in the old buffered 10.6 ppg brine. The rationale for HEA5 to maintain mechanical integrity (>37 hrs. vs. reduced time of 15+ hrs.) is unknown. It may be possibly (1) due to breakdown of the inhibited breaker over time (2) because of the added inhibitors it might have coated pressure vessel surfaces, preventing reaction between the fluid and vessel metallurgy, preserving activity of the fluid. The Breaker I with hydronium ions (H3 O +) preserved may have resulted in accelerated degradation of the installed DPN. This is representative and the most likely case, wherein an active, flowing inhibited breaker will interact with BR-DPNs’ in the wellbore. Our HEA5 (and all developed formulations) have repeatedly survived 15 hrs. in 10.6 ppg brine and > 8+ factor of safety (FOS) hours in uninhibited breaker or old inhibited counterpart.
DOI: 10.2118/228876-ms