Comprehensive analysis of 304H stainless steel tube

1、 Core characteristics and compositional differences

304H stainless steel tube is a high carbon derivative of 304 stainless steel, designed specifically for high-temperature environments. Its main components are similar to the 304 base model (chromium 18% -20%, nickel 8% -10.5%), but the carbon content is increased to 0.04% -0.10%, significantly enhancing high-temperature strength and creep resistance.

High temperature performance: suitable for long-term service environments below 870 ℃, better than ordinary 304 (temperature resistance of 800 ℃);

Corrosion resistance: It has basic corrosion resistance to oxidizing acids, alkaline solutions, etc., but requires solution treatment after welding to avoid intergranular corrosion.

2、 Application Fields and Advantages

304H, with its high carbon characteristics, is mainly used in high-temperature and high-pressure scenarios:

Energy and boiler equipment: such as power plant boiler superheater tubes and heat exchanger tubes, need to withstand continuous high temperature steam;

Chemical reaction vessels: high-temperature reaction vessels, cracking furnace pipelines, requiring materials to maintain mechanical stability in corrosive media;

Petroleum refining equipment: high-temperature cracking unit and oil and gas transportation pipeline.

3、 International standards and brand comparison

American standard: ASTM A213/A312 (corresponding to grade S30409);

Chinese standard: GB/T 20878-2007 (grade 07Cr19Ni10);

European standard: EN 10216-2 (designation 1.4948).

4、 Key points for selection and processing

Component verification: Carbon content (0.04% -0.10%) and chromium nickel ratio need to be confirmed through spectral detection;

Processing technology: Priority is given to cold drawn seamless tubes to ensure stable mechanical properties at high temperatures;

Welding requirements: Low carbon welding materials (such as ER308L) should be used, and solution treatment should be carried out after welding to eliminate the risk of carbide precipitation.