COMMON TRADE NAMES: 25 Chrome Duplex, 25Cr, SM25CR®, VM® 25, 2507, Duplex 2507
25 Chrome (UNS S31260), also referred to as 2507 Duplex or Duplex 25 Chrome, is a cold hardened duplex stainless steel intended for corrosion resistance in sweet (CO2) and mildly sour (H2S) environments with high chloride content, requiring high strength up to 450°F.
25 Chrome offers increased resistance to the effects of CO2 , chlorides, pH, and temperatures relative to 22 Chrome allowing use as downhole tubular components, packers, and other subsurface equipment in deeper wells with high-pressure and high-temperature (HPHT) conditions where pitting corrosion from high chlorides are a concern.
This alloy is classified in MR0175/ISO15156 as a duplex stainless steel having a Pitting Resistance Equivalent Number ≤40, suitable for H2S partial pressure ≤0.3 psi.
|≤ 0.03||24 - 26||5.5 - 7.5||BAL||≤ 1||≤ 0.75||2.5 - 3.5||0.2 - 0.8||≤ 0.03||≤ 0.03||0.1 - 0.5||0.1 - 0.3|
|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 2 Category 25-7-3
|NACE MR0175/ISO 15156
H2S Sour Service Limits
|H2S ≤ 3.0 psi,
Temp ≤ 450°F
|H2S ≤ 3.0 psi|
|140||140||160||145||9||38||140 Grade not recommended for sour service|
|Elastic Modulus||psi x 106||29||28.2||27|
|Thermal Conductivity||Btu/ft h °F||8||9||10|
|Specific Heat||Btu/lb °F||0.12||0.12||0.12|