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ASTM A334 and ASME SA334 are standards that cover several grades of minimum-wall-thickness, seamless and welded, carbon and alloy-steel tubes intended for use at low temperatures. These standards are typically applied in the context of heat exchanger, condenser, and similar heat transfer applications.
ASTM A334
ASTM A334 is a standard specification established by ASTM International, a globally recognized leader in the development and delivery of voluntary consensus standards. This specification covers nominal (average) wall seamless and welded carbon and alloy steel tubes intended for use at low temperatures. The steel grades covered by this specification include Grade 1, Grade 3, Grade 6, Grade 7, Grade 8, Grade 9, and Grade 11.
The mechanical properties of these steel grades vary, making them suitable for different applications. The tubes are typically manufactured by a seamless or welding process, with no filler metal added. Heat and product analysis must be performed on the steel, and it must conform to the specified chemical composition requirements.
ASME SA334
ASME SA334 is a standard specification by the American Society of Mechanical Engineers (ASME). ASME is also a globally renowned organization that develops standards to provide safety, reliability, and efficiency in multiple engineering disciplines. ASME SA334 covers several grades of minimum-wall-thickness tubes for use in low-temperature service.
The grades covered by ASME SA334 are similar to those of ASTM A334. The tubes are typically manufactured by a seamless or welding process, but the welding procedure should be suitable for the grade of steel being used and will not affect the performance of the final product.
Both ASTM A334 and ASME SA334 standards specify requirements for the tubes’ mechanical properties, chemical composition, testing, marking, and methods of manufacturing. These tubes are typically used in heat exchanger and condenser applications, where the operating environment is at low temperatures.
As of my knowledge cutoff in September 2021, this is the most accurate information. For any updates or changes beyond this date, please refer to the latest publications or consult with industry experts.
ASTM A334 is a standard specification for several grades of minimum-wall-thickness, seamless and welded, carbon and alloy-steel tubes intended for use at low temperatures. The standard covers several grades, each with different chemical and mechanical properties. Here’s a basic overview of the grades you mentioned:
1. Grade 1
ASTM A334 Grade 1 is the most common grade. It’s a carbon steel intended for use at low temperatures. It’s known for its excellent toughness and high ductility, making it suitable for applications that require resistance to shock or vibration.
2. Grade 3
ASTM A334 Grade 3 is a alloy steel that contains Nickel (3.18-3.82%). It offers excellent toughness and high impact resistance at very low temperatures, even lower than those suitable for Grade 1.
3. Grade 6
ASTM A334 Grade 6 is a commonly used grade that contains 0.29%-0.93% Carbon, 0.40-1.06% Manganese and a small percentage of other elements. This grade provides a good balance of strength and ductility, and is often used for pressure containing parts and structural applications.
4. Grade 7
ASTM A334 Grade 7 contains a higher percentage of Nickel (8.0-9.0%) compared to Grade 3. This makes it an excellent choice for extremely low temperature applications, as the high Nickel content significantly improves its toughness at low temperatures.
5. Grade 8
ASTM A334 Grade 8 is a high-strength low-alloy steel that contains 8.40-9.6% Nickel. This grade offers superior toughness at very low temperatures, making it suitable for the most demanding low-temperature applications.
6. Grade 9
ASTM A334 Grade 9 is a high-strength low-alloy steel that contains 1.60-2.24% Nickel. It’s known for its high strength and good resistance to corrosion and oxidation.
7. Grade 11
ASTM A334 Grade 11 is a high-strength low-alloy steel that contains 1.60-2.24% Nickel. It’s known for its superior strength, good ductility, and excellent resistance to corrosion and oxidation.
The specific chemical composition of each grade determines its mechanical properties and suitability for specific applications. These tubes are commonly used in heat exchanger and condenser applications, where the operating environment is at low temperatures.
Chemical Requirements for ASTM A334 Grade 1 Seamless Tubes
| Grade | Mfg. Process | Chemical composition(%) | ||||||||
| C | Si | Mn | P | S | Ni | Cr | Mo | Others | ||
| Grade 1 | S, E, AT | 0.30Max | – | 0.40~1.06 | 0.05Max | 0.60Max | – | – | – | (STBL450) |
| Grade 3 | S, E, AT | 0.19Max | 0.18~0.37 | 0.31~0.64 | 0.05Max | 0.050Max | 3.18-3.82 | – | – | – |
| Grade 6 | S, E, AT | 0.30Max | 0.10Max | 0.29~1.06 | 0.048Max | 0.058Max | – | – | – | – |
| Grade 7 | S, E, AT | 0.19Max | 0.13~0.32 | 0.90Max | 0.04Max | 0.050Max | 2.03~2.57 | – | – | (STBL690) |
| Grade 8 | S, E, AT | 0.18Max | 0.13~0.32 | 0.90Max | 0.045Max | 0.045Max | 8.40~9.60 | – | – | (Cu 0.75~1.25) |
| Grade 9 | S, E, AT | 0.20Max | – | 0.40~1.06 | 0.045Max | 0.50Max | 1.60~2.24 | – | – | – |
Tensile Requirements for ASTM A334 steel pipe
| Grade | Tensile Test MPa or N/mm2 | Remaks (Similar to JIS) |
Possibility Temperature | |
| Min Yield point | Tensile Strength | |||
| Gr. 1 | 205 | 380Min | Impact Test(J) 2V 18 |
|
| Gr. 3 | 240 | 450Min | 2V 18 | |
| Gr. 6 | 240 | 415Min | 2V 18 | |
| Gr. 7 | 240 | 450Min | 2V 18 | |
| Gr. 8 | 520 | 690Min | 2V 18 | |
| Gr. 9 | 315 | 435Min | 2V 18 | |
material comparison tables for ASTM A334 steel pipe
| ASTMSTANDARD | UNS NO. | KOREA/JAPANES | GERMAN | BRITISH | FRENCH | ITALIAN | |||||||||||
| KS/JIS Symbol | KS/JIS Numbe | Remarks | DIN Type | DIN Number |
Materiral Number |
Remarks | B.S Number |
B.S Grade | Remarks | AFNOR Type | NF Number | Ramarks | UNI Type | UNI Number | Ramarks | ||
| A 334 Seamless and Welded C-ans Alloy Steel Tubes for Low-Tempersture Service |
|||||||||||||||||
| Grade 1 | K03008 | STLT 39 / STbL 380 | D3571 / G 3464 | TT St 41N | 1.0437 | WBL-680(3b) | (3) | TU 42 BT | A49-230 | (32) | C 15 | 5949 | (6)Seamless Only | ||||
| Grade 3 | K31918 | STLT 46 / STBL 450 | D3571 / G 3464 | 10 Ni 14 | 1.5637 | WBL-680(3b) | 3603 | FS 503 LT 100 | CAT.2 | TU 16 N 14 | A49-230 | (3c) | 18 Ni 14 | 5949 | Seamless Only | ||
| Grade 6 | K03006 | (3) | TT St 45 N | 1.0456 | WBL-680(3b) | 3603 | FS 410 LT 50 | CAT.2 | TU A 42 BT | A49-230 | (29) | C 20 | 5949 | Seamless Only | |||
| Grade 8 | K31340 | STLT 70 / STBL 690 | D3571 / G 3464 | X8 Ni 9 | 1.5662 | WBL-680(3b) | 3603 | FS 590 LT 196 | CAT.2 | TU Z 11 N 9 | A49-230 | (6) | 12 X Ni 09 | 5949 | Seamless Only | ||
