Oil and Gas
Produced fluids combine chlorides, hydrogen sulphide, carbon dioxide and pressure, which is the combination austenitic stainless handles worst. Chloride stress corrosion cracking and sulphide stress cracking both have to be designed out, and the material has to meet NACE MR0175 / ISO 15156 limits on hardness. Duplex and super duplex usually win here because the strength advantage also reduces wall thickness and weight.
What gets specified in oil & gas
Ordered by how commonly they are called for in this sector.
- UNS S31803 / S32205 / S32550 / S32750 / S32760Duplex / Super DuplexPREN 41
Roughly equal austenite and ferrite. Around twice the yield strength of 316L.
- UNS S31600 / S31603316 / 316LPREN 25
304 plus 2–3% molybdenum. The standard answer to chlorides and mild acids.
- UNS S31254254 SMOPREN 43
6% molybdenum super-austenitic with nitrogen. PREN above 42.
- UNS S1740017-4 PHPREN 20
Martensitic PH grade. Machine soft, then age to tensile strengths above 1300 MPa.
- UNS N08904904LPREN 35
High nickel, high molybdenum, with copper. Built for sulphuric acid service.
Applications
06- Subsea and topside process piping
- Manifolds and flowlines
- Wellhead and christmas tree components
- Separator and scrubber internals
- Downhole tools and completion hardware
- Instrumentation tubing
Governing standards
04- NACE MR0175 / ISO 15156
- API 6A
- API 5LC
- ASTM A790
Verification available
10- Spectrometer
- Chemical Testing Laboratory
- Positive Material Identification (PMI)
- Spectro Test
- Tensile Testing Machine
- Hardness Testing Machine
- Portable Hardness Tester
- Flattening Test
- Reverse-Bend Test
- Hydrostatic Test Machine
What oil & gas buys
Other industries
Supplying into oil & gas?
Send the specification and service conditions. We will confirm the grade, the availability and the documentation you will need.