ASTM A333 Grade 6 Carbon Steel Seamless Pipe
Dec 04, 2025
A333 Gr6 Carbon Steel Low Temp Seamless Steel Pipes Description
ASTM A333 Gr.6 is a low-temperature steel pipe standard designed for fluid transfer and heat exchange applications in environments ranging from -45°C to -195°C. ASTM A333 Gr.6 cryogenic pipes offer excellent corrosion resistance, mechanical properties, and reliability, meeting diverse operational demands in cryogenic conditions.
ASTM A333 Gr. 6 chemical composition:
|
Grades |
C.max |
Si min |
Mn |
P |
S |
|
Gr. 6 |
0.30 |
0.1 |
0.29-1.06 |
≤0.025 |
≤0.025 |
ASTM A333 Gr. 6 mechanical property:
|
Grades |
Tensile strength Rm |
Yield strength YS |
Enlongation A(％) |
|
Gr. 6 |
415 |
240 |
≥16.5 |
Tolerance of SA333 Gr6 Pipe
| Tolerance, % | Outside Diameter, inch |
|---|---|
| +22.5/-12.5 | 3≤OD≤18, WT/OD≤5% |
| +20.0/-12.5 | 1/8≤OD≤2-1/2 |
| +22.5/-12.5 | OD≥20, WT/OD≤5% |
| +15.0/-12.5 | 3≤OD≤18, WT/OD>5% |
| +15.0/-12.5 | OD≥20, WT/OD>5% |
Heat Treatment Process for A333 Gr.6
Importance of Heat Treatment
Heat treatment enhances the performance of A333 Gr.6 cryogenic pipes, significantly improving impact resistance. In the as-manufactured state, these pipes exhibit a microstructure dominated by coarse, unevenly distributed ferrite and pearlite, resulting in reduced impact toughness at low temperatures. Post-heat treatment, the microstructure transforms into a uniform tempered sorbite with martensitic morphological characteristics, optimizing both mechanical properties and cryogenic resilience.
Process Steps
This treatment not only refines standard mechanical properties but also drastically improves low-temperature impact toughness. Typically, A333 Gr.6 pipes undergo the following heat treatment steps:
Heating to ≥1500°F (815°C).
Quenching in a liquid medium.
Reheating to an appropriate tempering temperature to stabilize the microstructure and enhance cryogenic toughness.
Test and inspection
Packaging and shipping
