Description
JIS G3462 STBA12 STBA13 STBA20 STBA22 STBA23 Alloy Steel Boiler Tube
Material
JIS G3462 Alloy Steel Boiler Tube specifies the requirements for alloy steel tubes used in boiler applications. The grades STBA12, STBA13, STBA20, STBA22, and STBA23 are designed to withstand high temperatures and pressures, making them suitable for various industrial applications, particularly in the energy sector.
Specification
The specifications outlined in JIS G3462 Alloy Steel Boiler Tube include the chemical composition, mechanical properties, and manufacturing processes of the alloy steel tubes. These tubes are primarily used in the construction of boilers and heat exchangers, where they must endure extreme conditions.
Key Features
- High Strength: These tubes are engineered to withstand high pressure and temperature, ensuring safety and reliability in boiler operations.
- Corrosion Resistance: The alloy composition provides resistance to oxidation and corrosion, extending the lifespan of the tubes in harsh environments.
- Weldability: The materials can be easily welded, allowing for flexible design and assembly in boiler systems.
- Durability: Designed for long service life, these tubes can operate effectively under extreme conditions, reducing maintenance costs.
Chemical Composition
The following table presents the chemical composition of the alloy steel grades STBA12, STBA13, STBA20, STBA22, and STBA23.
Grade | C (%) | Si (%) | Mn (%) | P (%) | S (%) | Cr (%) | Mo (%) | Ni (%) |
---|---|---|---|---|---|---|---|---|
STBA12 | 0.12 | 0.20 | 0.40 | 0.025 | 0.025 | 0.50 | 0.10 | 0.30 |
STBA13 | 0.13 | 0.20 | 0.50 | 0.025 | 0.025 | 0.50 | 0.10 | 0.30 |
STBA20 | 0.20 | 0.20 | 0.60 | 0.025 | 0.025 | 0.50 | 0.10 | 0.30 |
STBA22 | 0.22 | 0.20 | 0.70 | 0.025 | 0.025 | 0.50 | 0.10 | 0.30 |
STBA23 | 0.25 | 0.20 | 0.80 | 0.025 | 0.025 | 0.50 | 0.10 | 0.30 |
Mechanical Properties
The mechanical properties of the alloy steel grades are crucial for their performance in high-stress environments. The following table summarizes these properties.
Grade | Yield Strength (MPa) | Tensile Strength (MPa) | Elongation (%) | Hardness (HB) |
---|---|---|---|---|
STBA12 | 235 | 400-510 | 20 | 120 |
STBA13 | 245 | 410-520 | 20 | 125 |
STBA20 | 265 | 430-540 | 20 | 130 |
STBA22 | 275 | 440-550 | 20 | 135 |
STBA23 | 290 | 450-560 | 20 | 140 |
Steel Grade
The grades STBA12, STBA13, STBA20, STBA22, and STBA23 are categorized under the JIS G3462 standard, which focuses on alloy steel tubes for boiler applications. Each grade is tailored for specific operational conditions, ensuring optimal performance.
Application
These alloy steel boiler tubes are primarily used in:
- Power Plants: For steam generation and heat transfer in electricity production.
- Industrial Boilers: In various manufacturing processes requiring steam or hot water.
- Heat Exchangers: For efficient heat transfer between fluids in chemical and petrochemical industries.
- Petrochemical Industries: In refining processes where high temperatures and pressures are common.
Possible Alternative Grades
While STBA12, STBA13, STBA20, STBA22, and STBA23 are commonly used, alternative grades may include:
- ASTM A335 P11: Suitable for high-temperature service.
- ASTM A335 P22: Offers good corrosion resistance and strength.
- EN 10216-2 P235GH: A European standard that provides similar properties for pressure applications.