High-pressure Boiler Tubes VS Ordinary Boiler Tubes

Boiler tube refers to steel products with openings at both ends and a hollow section, with a large ratio of length to circumference. They are mainly divided into seamless steel pipe and welded steel pipe. In boiler manufacturing and application, high-pressure boiler tube and ordinary boiler tube (low and medium pressure boiler tubes) are two common pipes. They have significant differences in many aspects, which determine their respective application scenarios and performance characteristics. There are significant differences between high-pressure boiler tubes and ordinary boiler tubes in many aspects. The following are the main differences between them:

Implementation standards

High-pressure boiler tubes implement the GB/T5310-2018 standard. Ordinary boiler tubes (low and medium pressure boiler tubes) implement the GB/T3087-2018 standard.

Use environment

The working pressure of high-pressure boiler tubes is generally above 9.8Mpa, and the working temperature is between 450℃ and 650℃.

The working pressure of ordinary boiler tubes (low and medium pressure boiler tubes) is generally not more than 5.88Mpa, and the working temperature is below 450℃.

Material

High-pressure boiler tubes are suitable for materials such as 20G, 20MnG, 25MnG, 15MoG, 20MoG, 12CrMoG, 15CrMoG, 12Cr2MoG, 12CrMoVG, 12Cr3MoVSiTiB, etc.

Ordinary boiler tubes (low and medium pressure boiler tubes) usually use materials such as 10# and 20#, which have good mechanical properties and certain heat resistance and are suitable for low and medium pressure boilers.

Performance requirements

High-pressure boiler tubes are often in high temperature and high pressure, high temperature flue gas and water vapor environments, so they have high requirements for materials, such as high durability, high oxidation resistance and organizational stability.

Although ordinary boiler tubes also need high temperature resistance, pressure resistance and oxidation corrosion resistance, their requirements are relatively low.

Price

Due to the special requirements of materials and performance, the price of high-pressure boiler tubes is usually higher than that of ordinary boiler tubes. The manufacturing process of high-pressure boiler tubes is usually more complicated and the material cost is higher, so the market price is relatively high.

Uses

High-pressure boiler tubes are mainly used to manufacture reheater tubes, gas guide tubes, superheater tubes, etc. of high-pressure and ultra-high-pressure boilers. These parts need to withstand extremely high pressure and temperature, so high-pressure boiler tubes must be used.

Ordinary boiler tubes are used to manufacture superheated steam tubes and boiling water tubes of various structural boilers. The working environment of these parts is relatively mild, and ordinary boiler tubes can meet their use requirements.

Testing and inspection

In addition to conventional mechanical property tests, flattening and water pressure tests, high-pressure boiler tubes also require grain size inspection and more stringent non-destructive testing.

The testing and inspection requirements of ordinary boiler tubes are relatively low, mainly conventional mechanical property tests and water pressure tests to ensure their reliability in low and medium pressure environments.

Summary

In summary, there are significant differences between high-pressure boiler tubes and ordinary boiler tubes in terms of implementation standards, use environment, materials, performance requirements, prices, uses, and testing and inspection. These differences enable them to meet the use requirements in different working environments.