ASTM A333 Grade 6 pipe for low temperature services description
GR6 is a seamless steel pipe material specifically designed for cryogenic environments within the ASTM A333 standard system. It belongs to the nickel-free cryogenic toughness steel category and is also known as aluminum-killed steel (fine-grained steel deoxidized with aluminum). This material undergoes special processing to maintain good toughness and structural stability even in extreme low-temperature environments ranging from -45℃ to -195℃, effectively preventing cryogenic brittle fracture. Compared to other cryogenic steels, GR6 material exhibits superior weldability and machinability, reducing engineering costs while ensuring cryogenic performance, making it an economical and efficient choice in cryogenic engineering.
ASTM A333 Grade 6 Pipe specification
A333 gr6 pipe Chemical Composition
| Compositions | Data |
| Carbon(max.) | 0.30 |
| Manganese | 0.29-1.06 |
| Phosphorus(max.) | 0.025 |
| Sulfur(max.) | 0.025 |
| Silicon | … |
| Nickel | … |
| Chromium | … |
| Other Elements | … |
Mechanical properties for ASTM A333 Grade 6 Alloy Steel
| Properties | Data |
| Tensile strength, min, (MPa) | 415 Mpa |
| Yield strength, min, (MPa) | 240 Mpa |
| Elongation, min, (%), L/T | 30/16.5 |
sa 333 gr 6 V.S. sa 312 tp 316
1. Material Type & Composition
| Aspect | SA-333 Gr.6 | SA-312 TP316 |
|---|---|---|
| Material Type | Low-temperature carbon steel | Austenitic stainless steel |
| Key Alloying Elements | Carbon (C), Manganese (Mn) | Chromium (Cr 16–18%), Nickel (Ni 10–14%), Molybdenum (Mo 2–3%) |
| Corrosion Resistance | Low; prone to rust in moist/corrosive environments | High; excellent resistance to oxidation, acids, and chlorides |
2. Temperature Suitability
| Aspect | SA-333 Gr.6 | SA-312 TP316 |
|---|---|---|
| Low-Temperature Performance | Designed for -50°F (-45°C) or colder (with impact testing) | Maintains toughness down to cryogenic temperatures (e.g., -320°F/-196°C) |
| High-Temperature Performance | Limited to moderate heat (not suitable for prolonged high-temp use) | Excellent up to 1600°F (870°C); retains strength and oxidation resistance |
3. Mechanical Properties
| Aspect | SA-333 Gr.6 | SA-312 TP316 |
|---|---|---|
| Tensile Strength | ~485 MPa (70,000 psi) | ~515 MPa (74,800 psi) |
| Yield Strength | ~275 MPa (40,000 psi) | ~205 MPa (30,000 psi) |
| Ductility | Good at low temps (due to impact testing requirements) | High ductility across a wide temperature range |
4. Applications
| Aspect | SA-333 Gr.6 | SA-312 TP316 |
|---|---|---|
| Typical Uses | - LNG pipelines - Arctic oil/gas systems - Cold storage vessels |
- Chemical processing - Food/pharmaceutical equipment - Marine environments - High-purity fluid systems |
| Environmental Suitability | Dry, non-corrosive low-temp environments | Corrosive, high-purity, or high-temp environments |
5. Cost & Availability
| Aspect | SA-333 Gr.6 | SA-312 TP316 |
|---|---|---|
| Cost | Lower (carbon steel pricing) | Higher (due to nickel/molybdenum content) |
| Availability | Widely available in standard pipe sizes | Readily available but may cost more for specialized forms |
6. Key Standards
| Aspect | SA-333 Gr.6 | SA-312 TP316 |
|---|---|---|
| Specification | ASTM A333/ASME SA333 | ASTM A312/ASME SA312 |
| Testing Requirements | Mandatory low-temp impact testing | Optional impact testing; focus on corrosion/pressure tests |
Test and inspection
Packaging and shipping
