ASTM A333 Grade 6 Seamless and Welded Steel Pipe for Low-Temperature Service
Dec 04, 2025
ASTM A333 Grade 6 LTCS Pipe description
A333 Gr.6 steel is a nickel-free steel, specifically an aluminum-deoxidized fine-grained steel with excellent low-temperature toughness. Hence, it is also termed aluminum-killed steel.
Conforming to the American ANSI/ASTM SA333 cryogenic steel standard, it is designed for service at minimum impact temperatures of -46°C. Its operational temperature range and fracture toughness values are comparable to China's domestic 16Mn steel (16Mn steel has a minimum service temperature of -40°C).
A333 Gr.6 cryogenic pipes deliver exceptional low-temperature performance, making them suitable for:
Low-temperature pressure vessel pipelines
Cryogenic heat exchanger tubing
operating within -45°C to -195°C.
SA 333 Gr 6 Lined Pipe Chemical Composition (%)
| C(max) | Mn | P(max) | S(max) | Si | Ni | |
| Grade 6 | 0.3 | 0.29 – 1.06 | 0.025 | 0.025 | 0.10 (min) |
ASTM A333 Grade 6 Carbon Steel Seamless Pipe Yield and Tensile Strength
| ASTM A333 Grade 6 | |
| Minimum Yield | 35,000 PSI |
| Minimum Tensile | 60,000 PSI |
ASTM A333 Grade 6 Carbon Steel Seamless Pipe Wall Thickness & Tolerance
| Outside Diameter, inch | Tolerance, % |
| 1/8≤OD≤2-1/2 | +20.0/-12.5 |
| 3≤OD≤18, WT/OD≤5% | +22.5/-12.5 |
| 3≤OD≤18, WT/OD>5% | +15.0/-12.5 |
| OD≥20, WT/OD≤5% | +22.5/-12.5 |
| OD≥20, WT/OD>5% | +15.0/-12.5 |
SA333 Gr.6 cryogenic pipes are primarily used in pressure vessels and piping systems requiring high strength and toughness at low temperatures. Specific applications include:
Petrochemical Industry:
Used in manufacturing reactors, heat exchangers, separators, and other equipment for LNG storage/transportation and cryogenic chemical reaction systems.
Natural Gas Processing & Cryogenic Equipment:
For low-temperature pressure vessel pipelines and cryogenic heat exchanger tubing in natural gas/coal processing, operating from -45°C to -195°C.
Cryogenic Storage & Liquefied Gas Transport:
Suitable for ultra-low-temperature cold storage facilities and pipelines transporting cryogenic liquefied gases.
Other Industrial Applications:
Scrubbing, purification, and desulfurization equipment in ethylene, propylene, urea, and synthetic ammonia production, along with cryogenic processing equipment in pharmaceutical manufacturing.
Test and inspection
Packaging and shipping
