Carbon Steel Boiler Tube – ASTM A192 / A210 Factory Direct Supplier | Huaxia-Steel
Carbon steel boiler tube is the seamless or welded pipe used for heat-exchanger, super-heater, water-wall, economizer, and high-pressure service in power station boilers, refinery process heaters, and industrial steam generators. The principal specifications are ASTM A192, A210, A213, A179, plus the European DIN 17175 and Chinese GB 3087 / GB 5310. Huaxia-Steel supplies factory-direct carbon steel boiler tube in OD 12.7 to 127 mm with wall thickness from 2.5 to 12.5 mm, hot-finished seamless and cold-drawn seamless conditions, with EN 10204 3.1 mill test certificate.
1. Specification Comparison
| Specification | Scope | Typical Use |
|---|---|---|
| ASTM A192 / A192M | Seamless carbon steel boiler tubes for high-pressure service | Superheater, economizer, water wall |
| ASTM A210 / A210M | Seamless medium-carbon steel boiler and superheater tubes (Grade A1, Grade C) | Boiler tubes, superheater tubes |
| ASTM A213 / A213M | Seamless ferritic and austenitic alloy-steel boiler tubes (T2, T11, T22, T91) | High-temperature service (covered in alloy-steel SKUs) |
| ASTM A178 / A178M | Electric-Resistance-Welded carbon steel boiler and superheater tubes | ERW boiler tubes, low-pressure service |
| ASTM A179 / A179M | Seamless cold-drawn low-carbon steel heat-exchanger and condenser tubes | Heat exchanger, condenser, low-pressure boiler |
| DIN 17175 St35.8 / St45.8 | Seamless carbon steel tubes for elevated temperature service | Boiler, superheater (European) |
| GB 3087 | Seamless steel tubes for low and medium-pressure boiler | Industrial boiler, low-medium pressure |
| GB 5310 | Seamless steel tubes for high-pressure boiler | Power station boiler (Chinese) |
| EN 10216-1 P235TR2 / P265TR2 | Seamless pressure steel tubes with specified elevated temperature properties | Boiler, process pipe (European) |
Each spec targets a specific temperature and pressure envelope. The carbon content, tensile requirements and Charpy vary accordingly. Most power station boiler tube buyers use either ASTM A192 (high-pressure) + A210 (medium-pressure) or DIN 17175 + EN 10216-1 for European projects.
2. ASTM A192 / A210 Chemistry
| Element (percent) | A192 | A210 Grade A1 | A210 Grade C |
|---|---|---|---|
| Carbon (C, max) | 0.06 to 0.18 | 0.18 max | 0.35 max |
| Manganese (Mn) | 0.27 to 0.63 | 0.27 to 0.93 | 0.29 to 1.06 |
| Phosphorus (P, max) | 0.035 | 0.035 | 0.035 |
| Sulfur (S, max) | 0.035 | 0.035 | 0.035 |
| Silicon (Si, min) | 0.10 | – | 0.10 (min) |
A192 has lower carbon (0.06 to 0.18 percent) for the highest weldability combined with high-temperature strength. A210 Grade A1 is the medium-strength alternative, and A210 Grade C carries higher carbon (0.35 max) for the highest strength but at the cost of weldability.
3. Mechanical Properties (ASTM A192 and A210)
| Property | A192 | A210 Grade A1 | A210 Grade C |
|---|---|---|---|
| Tensile Strength (MPa, min) | 325 | 415 | 485 |
| Yield Strength (MPa, min) | 180 | 255 | 275 |
| Elongation, 50 mm (percent, min) | 35 | 30 | 30 |
| Hardness, HRB | 77 max | 79 max | 89 max |
| Flattening test | as required | as required | as required |
| Flaring test | as required | as required | as required |
A192’s 35 percent minimum elongation is high, indicating the low-carbon chemistry and the focus on forming and bending. A210 C’s 485 MPa minimum tensile is intended for superheater applications where dimensional stability at temperature is critical.
4. DIN 17175 / EN 10216-1 Chemistry and Properties
| Property | St35.8 (1.0305) | St45.8 (1.0405) |
|---|---|---|
| Carbon (C, max) | 0.17 | 0.21 |
| Silicon (Si, min) | 0.10 | 0.10 |
| Manganese (Mn) | 0.40 min | 0.40 min |
| Yield (MPa, min) @ RT | 235 | 255 |
| Tensile (MPa) @ RT | 360 to 480 | 410 to 530 |
| Yield at 300 deg;C (MPa, min) | 175 | 195 |
| Yield at 400 deg;C (MPa, min) | 155 | 175 |
| Yield at 500 deg;C (MPa, min) | 130 | 140 |
Note the elevated temperature yield values – both grades sustain usable strength up to 500 deg;C, with St45.8 stronger than St35.8 by approximately 10 to 15 MPa at every temperature.
5. Size Range (per spec)
| Parameter | A192 | A210 | DIN 17175 | GB 3087 |
|---|---|---|---|---|
| OD (mm) | 12.7 to 127 | 12.7 to 127 | 10 to 273 | 10 to 426 |
| Wall (mm) | 2.5 to 12.5 | 2.5 to 12.5 | 2.0 to 40 | 2.0 to 20 |
| Length (m) | 3 to 12 (custom) | 3 to 12 (custom) | 2 to 12 (custom) | 3 to 12 (custom) |
Heavy OD above 127 mm is supplied as hot-finished seamless pipe (ASTM A106 Gr.B or A335 P11) rather than boiler tube. Below 12.7 mm OD, the tube is typically a heat-exchanger tube (ASTM A179 or A213) rather than a boiler tube.
6. Manufacturing and Delivery
- Hot-finished seamless: Hot piercing followed by mandrel rolling. Surface is hot-rolled scale, dimensional tolerance approximately +/- 0.5 mm. Economical for thick walls and heavy diameters.
- Cold-drawn seamless: Hot-finished tube further cold-drawn through dies, optionally with annealing. Tight tolerance (OD +/- 0.10 mm), smooth surface, improved mechanical properties.
- Cold-finished + bright annealed: For U-tube heat exchangers. Cold-drawn then bright-annealed in protective atmosphere to restore ductility.
Standard delivery is cold-drawn and annealed for OD below 60 mm and wall below 5 mm. Above this, hot-finished is more cost-effective.
7. Testing and Acceptance
Each tube is hydrostatically tested at the mill to confirm pressure containment. Supplementary tests per ASTM A450 / EN 10246:
- Flattening test – ductility check
- Flaring test – flange-formability
- Reverse-bending test for cold-drawn tubes
- Hardness test (Rockwell HRB or Vickers HV)
- Surface inspection per ASTM A450 / A1012
- Eddy current or ultrasonic test for heavy tubes
- Dimensional measurement per ASME B36.10 / B36.19
For power-station specification, additional testing is required:
- 100 percent hydrostatic test to 1.5x design pressure
- Charpy impact testing for low-temperature service (cold start)
- Through-thickness hardness survey
- Metallographic examination at one location per heat
8. Welding and Bending
Carbon steel boiler tube is welded using TIG (GTAW) for root pass and SMAW for fill. Boiler tube bends are made hot or cold depending on radius; minimum bend radius is 2 x OD for carbon steel without wrinkling. Tube expanders (hydraulic or mechanical) are used to expand into boiler tube sheets.
For new boiler builds, all welding procedure qualification per ASME Section IX is mandatory. Welding consumables are matched to the parent tube:
- For A192 / A210 A1: ER70S-G, E7018
- For A210 C: ER80S-G, E8018-C1
- For DIN 17175 St35.8 / 45.8: per EN 13480 / EN 12952
9. Quality Assurance
Huaxia-Steel carbon steel boiler tube is produced by ISO 9001 mills with EN 10204 3.1 / 3.2 MTC. Each tube is marked with heat number, spec, dimensions, and mill stamp at both ends. For power-station specification, additional third-party inspection (BV, SGS, TUV, or Class Society) can be arranged with witnessed testing.
10. Cross Reference
| ASTM | DIN | GB | EN |
|---|---|---|---|
| A192 | St35.8 | 20G (GB 5310) | P235TR2 |
| A210 A1 | St45.8 | 20G (GB 5310) | P265TR2 |
| A210 C | 17Mn4 | 15MnV / 12Cr1MoV | 16Mo3 |
| A179 | St37.4 / St44.4 | 10# (GB 3087) | P195TR2 |
11. Applications
- Power station boiler tubes for super-heater, re-heater, economizer, water wall
- Industrial steam boilers (paper mills, textile, chemical)
- Heat exchanger and condenser tubes (oil refineries, chemical plants)
- Cogeneration and combined-cycle boilers
- Biopower and waste-to-energy boiler
- Marine boiler feed lines and economizer
12. Frequently Asked Questions
Q1: When should A210 Grade C be used instead of A192?
A210 C is specified when the tube operates in the highest temperature envelope (typically above 510 deg;C superheater). At lower temperatures and high pressure, A192 is more appropriate because of its better weldability and lower CEV.
Q2: What is the lead time for special size tubes?
Stock sizes (OD 25 to 88.9 mm, wall 2.5 to 8 mm) ship from distributor within 5 to 10 days. Mill production for special sizes requires 35 to 55 days, depending on the size and quantity.
Q3: Can A192 tubes be supplied with hot-dip galvanized coating?
Yes but not common. Galvanizing adds 50 to 80 microns of zinc for short-term storage. Internal scaling inside the tube is not affected; external corrosion is reduced.
Q4: What is the maximum temperature for A192?
A192 is recommended for service temperatures below 460 deg;C. Above 460 deg;C, creep and oxidation reduce the design life. Switch to alloy grades (T11, T22, T91) for higher temperatures.
Q5: Are boiler tubes seamless or welded?
For high-pressure service (A192, A210, DIN 17175), tubes are seamless. Welded tubes per ASTM A178 are used for low-pressure boiler and economizer service where the seam efficiency factor is acceptable in design.
13. Conclusion
Carbon steel boiler tube covers the broadest range of pressure-temperature service in the boiler industry. Specify by service temperature: A192 for high pressure below 460 deg;C, A210 A1 for high pressure mid temperature, A210 C for high pressure high temperature. Specify hydrostatic test at the mill. Confirm length and bend schedule with the boiler manufacturer before order.
14. Get a Quote from Huaxia-Steel
Huaxia-Steel supplies factory-direct carbon steel boiler tube per ASTM A192, A210, A179, DIN 17175, EN 10216-1, GB 3087 / 5310 from ISO 9001 mills with EN 10204 3.1 / 3.2 MTC. OD 12.7 to 127 mm, wall 2.5 to 12.5 mm, length to 12 m. Send your drawing, dimensions and spec for a quotation within 24 hours.
