ASTM A178 Tubes are electric resistance welded carbon steel tubes widely used in boiler tubes, heat exchangers tubes, condensers, and similar heat transfer applications. These tubes are manufactured in accordance with ASTM A178 and ASME SA178 specifications and are available in Grades A, C, and D to suit different temperature and pressure requirements.
We supply ASTM A178 ERW Tubes with precise dimensional accuracy, controlled chemical composition, and excellent mechanical strength. ASME SA178 Tubing is specifically designed for high-temperature service in boiler and superheater systems where reliability and durability are critical.
ASTM A178 Tubes Specifications
| Property | Details |
|---|---|
| Specification | ASTM A178 / ASME SA178 |
| Type | Electric Resistance Welded (ERW) |
| Grades | Grade A, Grade C, Grade D |
| Outer Diameter | As per ASTM standard requirements |
| Wall Thickness | As per boiler and heat exchanger requirements |
| Length | Single random, double random, or cut length |
| End | Plain End (PE), Beveled End (BE) |
ASTM A178 ERW Tube manufacturing ensures a uniform weld structure and strong metallurgical bonding suitable for pressure applications.
ASTM A178 Electric Resistance Welded Tube Grades
ASTM A178 Tubes are available in the following grades:
Grade A – Low carbon steel grade used for heat exchangers and low-pressure boiler applications.
Grade C – Medium carbon grade offering improved strength and temperature resistance.
Grade D – Higher strength carbon steel grade suitable for more demanding boiler applications.
Each ASTM A178 Tube grade is tested for chemical composition and mechanical properties to ensure compliance with ASTM and ASME standards.
Chemical Composition of ASME SA 178 Boiler Tubes
ASME SA178 Tubing is manufactured with controlled carbon, manganese, phosphorus, sulfur, and silicon content. The chemical composition varies depending on Grade A, C, or D and ensures:
| Element | Grade A (Low Carbon) | Grade C (Medium Carbon) | Grade D (Carbon–Manganese) |
|---|---|---|---|
| Carbon (C) | 0.06 – 0.18 | 0.35 max | 0.27 max |
| Manganese (Mn) | 0.27 – 0.63 | 0.80 max | 1.20 – 1.80 |
| Phosphorus (P) | 0.035 max | 0.035 max | 0.035 max |
| Sulfur (S) | 0.035 max | 0.035 max | 0.035 max |
| Silicon (Si) | 0.25 max | Not specified | 0.10 – 0.40 |
Material Properties of ASME SA178 Carbon Steel Tubes
ASTM A178 Tubes provide excellent mechanical properties required for pressure service applications. The tensile strength, yield strength, and elongation values vary by grade and are tested as per ASTM A178 / ASME SA178 standards.
| Property | Grade A | Grade C | Grade D |
|---|---|---|---|
| Tensile Strength | 47,000 psi [325 MPa] | 60,000 psi [415 MPa] | 70,000 psi [485 MPa] |
| Yield Strength | 26,000 psi [180 MPa] | 37,000 psi [255 MPa] | 40,000 psi [275 MPa] |
| Elongation in 2" (50 mm) | 35% | 30% | 30% |
| Hardness (Max) | 77 HRB | 85 HRB | 89 HRB |
ASTM A178 Tubing Manufacturing Process
ASTM A178 ERW Tubes are manufactured using the electric resistance welding process. The steel strip is formed into a tubular shape and welded longitudinally using controlled electrical resistance heat without filler metal.
After welding, ASME SA178 Tubing undergoes:
- Heat treatment (as required by grade)
- Sizing and straightening
- Non-destructive testing
- Dimensional inspection
The finished ASTM A178 Tube is inspected for surface defects, wall thickness variation, and weld integrity before dispatch.
Why ASTM A178 Tubes Are Used in Boilers
ASTM A178 ERW tubes are designed for boiler and heat exchanger services where pressure containment and thermal efficiency are critical. The ERW process ensures uniform wall thickness and dimensional accuracy, which improves heat transfer and mechanical reliability in steam systems.
The smooth internal surface of ASTM A178 Tubes reduces flow resistance and minimizes scaling risk during prolonged high-temperature operation. These tubes are suitable for continuous thermal cycling and fluctuating pressure conditions commonly found in industrial boilers and power plants.
Applications of ASTM A178 Tubes
ASTM A178 Tubes and ASME SA178 Tubing are used in:
- Water tube boilers
- Fire tube boilers
- Heat exchangers
- Condensers
- Economizers
- Superheaters
Their ERW construction ensures reliable performance in thermal and pressure-based applications.
Testing & Inspection of ASTM A178 ERW Tubes
Each ASTM A178 Tube is tested in accordance with ASTM A178 / ASME SA178 requirements. Standard inspections include:
- Chemical analysis
- Mechanical testing
- Flattening and crush testing
- Hydrostatic testing
- Eddy current or electric testing
- Dimensional tolerance verification
Mill test certificates are provided as per EN 10204 3.1 upon request.
We supply ASTM A178 Tubes for domestic and export markets with consistent quality control and documentation support. Contact us today for a competitive quote or to discuss your project’s custom specifications.
Related Products
- ASTM A210 Grade A1 Tubes
- ASME SA192 Boiler Tubes
- ASTM A179 Boiler Tubes
- ASME SA214 Boiler Tubes
- Boiler & Heat Exchanger Tubes
- Carbon Steel Welded Tubes
Frequently Asked Questions About ASME SA178 Tubes
Is ASTM A178 suitable for boiler applications?
Yes, ASTM A178 tubes are specifically manufactured for boiler and heat exchanger service under pressure and temperature conditions.
What is SA178A material?
SA178A is a carbon steel grade with good weldability and mechanical strength, commonly used in low to medium pressure boilers.
What is the difference between ASTM A178 and A210?
ASTM A178 tubes are electric resistance welded (ERW), while ASTM A210 tubes are seamless and typically used for higher-pressure boiler systems.
Are ASME SA178 tubes available in custom sizes?
Yes, SA178 tubes are available in custom diameters, wall thicknesses, and cut lengths as per project requirements.