_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 230027, “Innovative Wireline-Perforation Strategy for Depleted HP/HT Reservoirs With High-Pressure Differentials, ” by Alhadi Zahmuwl, SPE, SLB, Art Hooker, TotalEnergies, and Adil Al Busaidy, SLB, et al. The paper has not been peer-reviewed. _ Perforating in high-pressure, high-temperature (HP/HT) wells requires extensive engineering preparation, particularly in multizone completions where perforation order is critical. Historically, coiled tubing has been the default conveyance under live-well conditions, but multizone HP/HT settings typically force a single-run interval that can expose depleted zones to damage as a result of high overbalance while adding cost, complexity, and surface footprint. This paper describes the engineering and execution of a wireline perforation program in a deep HP/HT completion. Conveyance Alternatives and Selection Perforating long intervals in HP/HT wells under pressure requires a conveyance method that balances mechanical strength, pressure containment, operational flexibility, and offshore deployment limitations. These include limited deck space, crane capacity, and accommodation for additional personnel. In the featured case, wireline was selected as the optimal conveyance method after evaluating mechanical requirements, operational risks, and rigsite limitations. The complete paper details some of the advantages of wireline over coiled tubing in these applications. This solution enabled the operation to meet well-perforation objectives without the logistical and technical burdens of coiled tubing, while enhancing control over zone-by-zone perforation exposure and maintaining operational efficiency without compromising safety or tool reliability. Cable Selection and Deployment Feasibility With wireline selected as the conveyance method, the next challenge was to ensure that the cable could reliably deploy long gun strings under HP/HT conditions. A 0. 28-in. -outer-diameter (OD), polymer-filled electric line with MP35N corrosion-resistant armor for hydrogen sulfide and CO2 was selected for this campaign. The cable design provided the combination of strength, pressure sealing, and reduced drag necessary for safe perforating in a live-well environment. The cable offered the following advantages over conventional alloy-armored designs: - The MP35N armor provided a high safe-working load, enabling deployment of 70–80 ft of 27/8-in. guns per run. - Conventional braided cables contain voids between armor layers, which act as potential gas-migration pathways. The polymer-filled MP35N cable eliminated these pathways with a void-free structure in which polymer fills all interstitial spaces between conductor and armor (Fig. 1). - The small 0. 28-in. -OD line reduced cable drag both in the wellbore and across flow tubes because hydraulic forces increase with larger cross-sectional area. The friction coefficient observed during the job was approximately 0. 166, significantly lower than values observed in previous campaigns using a larger 0. 32-in. -OD cable.
Chris Carpenter (Sun,) studied this question.