COMMON TRADE NAMES: SMC276®, INCONEL® Alloy C-276, Hastelloy® C-276
C276 (UNS N10276) is a cold hardened nickel-based alloy intended for the most extreme well conditions up to 450°F.
In addition to its exceptional corrosion resistance under the most severe conditions, higher strengths may be achieved with C276 than other nickel alloys. Therefore, the alloy is commonly used for downhole tubular components, packers, and other subsurface equipment under the most extreme environmental conditions found in high-pressure, high-temperature (HPHT) wells, Saltwater Injection wells, and Acid Gas Injection (AGI) wells. However, all environmental factors, including H2S, CO2 , temperature, pH, and chloride concentration, should be considered before final material selection.
The alloy is classified in MR0175/ISO15156 as a type 4e alloy, with no restrictions to a partial pressure of H2S below 400°F and resistant to 1000 psi H2S at 450°F.
|≤ 0.02||14.5 - 16.5||BAL||4 - 7||≤ 1||≤ 0.08||15 - 17||≤ 2.5||≤ 0.03||≤ 0.03||≤ 0.35||3 - 4.5|
|Steel Making||Made by electric furnace process or blast furnace followed by Vacuum Oxygen Decarburization (VOD) process or Argon Oxygen Decarburization (AOD) Process|
|Pipe Making||Manufactured by traditional tube manufacturing processes, High strength tubulars should be furnished in cold worked condition|
|Heat Treatment||Solution Annealing Process before final cold drawing|
API 5CRA / ISO 13680 Group 4 Category 15-60-16
|NACE MR0175/ISO 15156
H2S Sour Service Limits
|110||110||140||125||11||35||Table A.14||No limit ≤ 400°F,
Refer to table for temperatures up to 450°F
|140||140||160||145||9||38||140 Grade not recommended for sour service|
|Elastic Modulus||psi x 106||29.8||29||28.3|
|Thermal Conductivity||Btu/ft h °F||5.9||6.4||7.5|
|Specific Heat||Btu/lb °F||0.1||0.1||0.1|