About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
|
Symposium
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Accelerated Testing to Understand the Long Term Performance of High Temperature Materials
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Presentation Title |
Exploring the Service Life Extremes of 716 in Highly Corrosive Environments |
Author(s) |
Timothy Dunne, Lei Zhao, Jiaxiang Ren, Peng Cheng, Yu Liu, Huailiang Liu |
On-Site Speaker (Planned) |
Timothy Dunne |
Abstract Scope |
716+ (UNS N07716) is a commonly selected alloy for multi-decade oilfield applications with established environmental guidance from NACE MR-0175. Based on thermodynamic calculations, the historical limit determined using low-pressure rated equipment could be extended significantly by accounting for non-ideal H2S phase behavior effects. Slow strain rate testing at 204°C with increasing H2S concentration determined a potential traditional ideal 800 psi H2S limit and non-ideal 1100 psi H2S limit. TM0177 c-ring was conducted at these concentrations with 1200-1360 psi CO2, 20-25% NaCl, with elemental sulfur at pressures of 2300 and 15000 psi total pressure for 90 days. One 15000 psi sample of nine unexpectedly cracked in a lower stress area outside of the highest stress apex area. Further microstructural analysis was conducted. The highest ever reported H2S 625+ testing simultaneously proved multi-decade use at least 200 psi H2S over the standard and the new revision allowing elemental sulfur is problematic. |
Proceedings Inclusion? |
Planned: |
Keywords |
Copper / Nickel / Cobalt, High-Temperature Materials, Environmental Effects |