What is ASTM/ASME A/SA213 Grade T5 boiler tube?
ASTM/ASME A/SA213 Grade T5 Boiler Tubes
High-performance ferritic alloy steel tubes for extreme temperature and pressure applications
Grade T5 Boiler Tube Overview
ASTM/ASME A/SA 213 Grade T5 is a seamless ferritic alloy steel boiler tube specifically engineered for high-temperature and high-pressure service environments. This chromium-molybdenum alloy steel is characterized by its exceptional creep strength and oxidation resistance at elevated temperatures.
Technical Insight: Grade T5 tubes maintain structural integrity at continuous operating temperatures up to 650°C (1200°F), making them ideal for superheater and reheater applications in modern power plants. The chromium content (4-6%) provides excellent oxidation resistance, while molybdenum (0.45-0.65%) enhances high-temperature strength and creep resistance.
ASTM/ASME A/SA 213 Grade T5 is a type of seamless ferritic alloy steel boiler tube designed for high-temperature and high-pressure service. It is manufactured to stringent specifications to ensure reliability in critical applications such as:
Power Generation
Superheaters, reheaters, and steam lines
Petrochemical Industry
Furnace tubes, heat exchangers, reformers
Oil and Gas
Heat recovery steam generators (HRSGs)
Industrial Boilers
High-pressure steam generation systems
Chemical Composition
| Element | Minimum | Maximum | Optimal Range | Function |
|---|---|---|---|---|
| Carbon (C) | - | 0.15% | 0.08-0.12% | Strength and hardenability |
| Manganese (Mn) | 0.30% | 0.60% | 0.40-0.55% | Deoxidizer, strength enhancement |
| Phosphorus (P) | - | 0.025% | <0.020% | Impurity control |
| Sulfur (S) | - | 0.025% | <0.015% | Impurity control |
| Silicon (Si) | - | 0.50% | 0.20-0.40% | Deoxidizer |
| Chromium (Cr) | 4.00% | 6.00% | 4.50-5.50% | Oxidation resistance |
| Molybdenum (Mo) | 0.45% | 0.65% | 0.50-0.60% | Creep strength |
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Trace Elements: Grade T5 may contain controlled amounts of other elements such as nickel (Ni) <0.50%, vanadium (V) <0.03%, and aluminum (Al) <0.04% to enhance specific properties without compromising weldability or high-temperature performance. Manufacturing Note: Chemical composition is tightly controlled during steelmaking to ensure consistent performance. Trace element analysis is performed using optical emission spectrometry for precision. |
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Mechanical Properties
| Property | Value | Test Method | Temperature Range | Significance |
|---|---|---|---|---|
| Tensile Strength | ≥415 MPa (60,200 psi) | ASTM A370 | Room Temperature | Structural integrity |
| Yield Strength | ≥205 MPa (29,700 psi) | ASTM A370 | Room Temperature | Deformation resistance |
| Elongation | ≥30% (in 2 in or 50mm) | ASTM A370 | Room Temperature | Ductility and formability |
| Hardness | ≤163 HB / 85 HRB | ASTM E10 / E18 | Room Temperature | Wear resistance |
| Creep Strength | 100 MPa (14,500 psi) | ASTM E139 | 600°C (1112°F) | Long-term stress resistance |
| Impact Toughness | ≥27 J (20 ft-lb) | ASTM A370 | -20°C (-4°F) | Fracture resistance |
Performance Advantages
High-Temperature Performance
- Exceptional creep resistance at 550-650°C
- Maintains strength during thermal cycling
- Low thermal expansion coefficient
- Resistant to thermal fatigue cracking
- Stable microstructure at high temperatures
Corrosion Resistance
- Superior oxidation resistance
- Resistant to steam corrosion
- Good sulfidation resistance
- Performs well in reducing atmospheres
- Resists graphitization in carbonaceous environments
Fabrication Advantages
- Excellent weldability with proper procedures
- Good formability and bendability
- Compatible with common joining methods
- Predictable heat treatment response
- Minimal sensitization during welding
Engineering Insight: Overall, ASTM/ASME A/SA 213 Grade T5 boiler tube has excellent high-temperature strength and resistance to corrosion and oxidation. Its balanced chromium-molybdenum composition provides superior performance in high-pressure steam environments, where creep resistance and microstructural stability are critical for long-term reliability. The combination of strength, oxidation resistance, and fabricability makes T5 a preferred choice for critical components in supercritical power plants.
Quality Assurance: Grade T5 tubes undergo rigorous testing including hydrostatic testing, ultrasonic examination, eddy current testing, and dimensional verification. All production batches include material test certificates (MTC) with full traceability to ensure compliance with ASME Section I and Section VIII requirements for pressure equipment.