Grades and Standards of Seamless High-Pressure Boiler Tubes

Seamless high-pressure boiler tubes are critical piping materials used in high-temperature, high-pressure boiler systems, and are widely applied in power plant boilers, industrial boilers, and pressure equipment. Common standards include Chinese GB/T 5310, American ASTM A106 / A335 (ASME SA106 / SA335), European EN 10216-2, and Japanese JIS G3455 / G3462. Steel grades cover carbon steel, low-alloy steel, and high-alloy heat-resistant steel, such as 20G, 15CrMoG, 12Cr1MoVG, P11, P22, P91, etc., possessing excellent high-temperature resistance, high-pressure resistance, and creep resistance, ensuring the long-term safe and stable operation of boiler systems.

SMLS High-Pressure Boiler Tubes

Against the backdrop of my country's rapid economic growth, the electric power industry, as a foundational industry, has experienced rapid development. Electricity is not only a source of power for industrial production but also a vital guarantee for people's daily lives. With increasing energy demand and the widespread construction of thermal power plants, the demand for high-pressure boiler tubes has steadily increased. As a key component of power plant boilers, seamless high-pressure boiler tubes play an irreplaceable role in energy equipment manufacturing.

Concept and Characteristics of Seamless High-Pressure Boiler Tubes

Seamless high-pressure boiler tubes are special-purpose seamless steel tubes primarily used in the manufacture of high-pressure, ultra-high-pressure, and even subcritical and supercritical thermal power generation boilers. Compared to ordinary seamless steel tubes, their greatest advantage lies in their ability to withstand complex operating conditions such as high temperatures, high pressures, and corrosive media for extended periods. Consequently, extremely stringent requirements are placed on their material, performance, and production processes.
This type of steel tube possesses the following basic characteristics:
High high-temperature pressure bearing capacity: Capable of long-term operation at temperatures between 400°C and 700°C.
Excellent oxidation and corrosion resistance: Resistant to oxidation and corrosion in high-temperature flue gas and steam environments.
Good Microstructure Stability: After rigorous heat treatment, the grain size and microstructure remain stable, reducing embrittlement and performance degradation during long-term use.

Both Strength and Toughness: Not only must the tube possess sufficient long-term strength, but it must also ensure impact and fatigue resistance.

Common Applicable Standards

The standard system for seamless high-pressure boiler tubes mainly includes Chinese standards, American standards, European standards, and Japanese standards.

1. Chinese Standards (GB)
GB/T 5310 "Seamless Steel Tubes for High-Pressure Boilers"
This is the most widely used standard for high-pressure boiler tubes in China, applicable to boiler pipelines operating at high pressure and above.
Common steel grades include:
20G, 20MnG, 25MnG, 15CrMoG, 12Cr1MoVG, 10Cr9Mo1VNb, etc.

2. American Standards (ASTM / ASME)
ASTM A106 / ASME SA106 (Seamless Carbon Steel Pipes for High-Temperature Service)
ASTM A335 / ASME SA335 (Seamless Alloy Steel Pipes)
Common grades include:
Gr.B, Gr.C, P11, P22, P91, P92, etc., widely used in thermal and nuclear power boiler systems.

3. European Standards (EN)
EN 10216-2 "Seamless Steel Tubes for Pressure Purposes"
Common steel grades:
P235GH, P265GH, 16Mo3, 13CrMo4-5, 10CrMo9-10, etc.

4. Japanese Standards (JIS)
JIS G3455 (Carbon Steel Pipes for High-Pressure Service)
JIS G3462 (Alloy Steel Boiler and Heat Exchanger Tubes)
Common steel grades:

STB410, STB510, STBA12, STBA22, STBA24, etc.

Common Steel Grades and Standards of Seamless High-Pressure Boiler Tubes

Seamless high-pressure boiler tubes are made of carbon steel, alloy steel, and stainless heat-resistant steel. Different steel grades are suitable for different operating conditions:
Carbon structural steels such as 20G, 20MnG, and 25MnG are suitable for medium- and low-pressure boilers.
Alloy structural steels such as 15MoG, 12CrMoG, 15CrMoG, 12Cr2MoG, 12Cr1MoVG, and 12Cr3MoVSiTiB are suitable for high-temperature and high-pressure boilers.
Stainless heat-resistant steels such as 1Cr18Ni9 and 1Cr18Ni11Nb are suitable for ultra-high-temperature environments.
The primary standard implemented is GB5310-1995 "Seamless Steel Tubes for High-Pressure Boilers." Specifications range from an outer diameter of 16 to 824 mm and a wall thickness of 2 to 65 mm.

The weight calculation formula is:

Where: D is the outer diameter and S is the wall thickness.