What Is ASTM A213 Stainless Steel Tube?
overview
ASTM A213 is the sanitary/thermal-duty specification for seamless austenitic stainless steel tubes used in boilers, superheaters, and heat exchangers. It defines chemistry, minimum mechanical properties (tensile and hardness), verification tests (including flattening, flaring, and hydrostatic or nondestructive electric testing), and ordering practices by OD × wall × length (minimum-wall or nominal-wall).
What A213 covers
- Product form: Seamless austenitic (and ferritic alloy) stainless steel tubes intended for boiler, superheater, and heat-exchanger service.
- How to specify: Order by OD × wall × length, choose minimum-wall or nominal-wall, and state grade, surface, tests, and documents.
- Typical stainless grades: TP304/TP304L, TP316/TP316L (TP321/TP347 on request for stabilization at elevated temperatures).
- Finish/condition: Furnished solution-annealed; surfaces commonly AP (annealed & pickled) or BA (bright annealed).
- Documentation: Heat/lot traceability with EN 10204 3.1 MTC; dimensional and test reports available with shipment.
ASTM A213 specification Requirements
Chemical Requirements
| Grade (TP) | C max | Mn | P | S | Si | Cr | Ni (%) | Mb |
| TP304 | 0.08 | 2 | 0.045 | 0.03 | 1 | 18-20 | 8-11 | |
| TP304L | 0.035 | 2 | 0.045 | 0.03 | 1 | 18-20 | 8-12 | |
| TP316 | 0.08 | 2 | 0.045 | 0.03 | 1 | 16-18 | 10-14 | 2-3 |
| TP316L | 0.035 | 2 | 0.045 | 0.03 | 1 | 16-18 | 10-14 | 2-3 |
Mechanical Requirements
| Grade | Tensile min (MPa) | Yield min (MPa) | Elongation in 50mm (%) | Hardness | |
| Brinell/Vickers | Rockwell | ||||
| TP304 | 515 | 205 | 35 | 192 HBW/200HV | 90 HRB |
| TP304L | 485 | 170 | 35 | 192 HBW/200HV | 90 HRB |
| TP316 | 515 | 205 | 35 | 192 HBW/200HV | 90 HRB |
| TP316L | 485 | 170 | 35 | 192 HBW/200HV | 90 HRB |
Heat treatment (annealed condition)
All ASTM A213 stainless steel pipes must be supplied in the heat-treated (annealed) condition per the specification.
| Grade (TP) | Temperature range (°C) | Cooling Media |
| TP304 | 1040 | water or other rapid cool |
| TP304L | 1040 | water or other rapid cool |
| TP316 | 1040 | water or other rapid cool |
| TP316L | 1040 | water or other rapid cool |
Permissible Variations from the Specified Wall Thickness
Permissible variations from the specified average wall thickness shall be 6 10 % of the specified average wall thickness for cold-formed tubes and, unless otherwise specified by the purchaser.
Common Applications
- Shell-and-tube heat exchangers (process and utility)
- Boilers, superheaters, economizers
- Condensers in power, chemical, and HVAC duty
- Thermal loops and process coils where seamless construction and stable high-temperature performance are required
FAQs
1. Is ASTM A213 a pipe or a tube standard?
Tube. A213 covers seamless tubes ordered by OD × wall × length for boiler/superheater/heat-exchanger service. For schedule pipe in pressure service, see ASTM A312. For welded heat-exchanger tubes, see ASTM A249.
2. What’s the difference between A213 and A249 or A269?
- A213: Seamless thermal-duty tubes for boiler/superheater/HX.
- A249: Welded thermal-duty tubes with post-weld cold work + final anneal for tube-sheet expansion.
- A269: General/instrumentation tubing (OD × wall) for non-sanitary service.
3. Which stainless grades are most common under A213?
TP304/TP304L and TP316/TP316L cover most duties. TP321/TP347 are selected for stabilization when long exposure to elevated temperature is expected.
4. What documents come with delivery?
Typically, EN 10204 3.1 MTC, dimensional checks, and test certificates (hydro/ECT) as specified. Heat/lot numbers appear on labels.
