【Daily Question】What are the requirements for steel used in boiler tubes? (Participation +2, Correct answer +5 wealth)

The basic requirements for the steel used in boiler and pressure vessel construction are mainly as follows: First, the materials used to manufacture boilers and pressure vessels must possess appropriate strength (primarily yield strength and tensile strength) to prevent plastic deformation or even fracture when under pressure. For boilers and medium- and high-temperature pressure vessels, the creep resistance of the materials must also be considered, and the high-temperature performance parameters of the materials, namely the creep limit and endurance strength, need to be determined. Secondly, the materials used to manufacture boilers and pressure vessels must possess good plasticity in order to prevent damage to these devices due to accidental overloading during use. Third, the materials used to manufacture boilers and pressure vessels should possess high toughness, so that they can withstand the impact loads that may occur during operation. Especially for pressure vessels operating at low temperatures or in low-temperature environments, it is essential to consider the impact toughness value of the material and conduct impact tests on that material at the operating temperature, in order to prevent brittle fracture of the vessel during operation.

Steel used for boilers must be resistant to high temperatures and pressures; therefore, it not only needs to have a certain strength but also sufficient creep resistance and toughness.

Steel used for boilers must be resistant to high temperatures and pressures; therefore, it not only needs to have a certain strength but also sufficient creep resistance and toughness.

The boiler drum is subjected to high operating pressure at the saturation temperature of the working fluid. During manufacturing, processes such as sheet rolling, stamping, and welding are involved. The steel used for boiler sheets must possess the following properties: (1) high strength, so as to thin the boiler walls as much as possible, which is beneficial for manufacturing, installation, and operation. (2) Good plasticity and toughness reduce the likelihood of cracks occurring during manufacturing processes such as cylinder sheet rolling and head stamping. (3) Steel plates have low notch sensitivity; the drum contains numerous openings and welds, which lead to stress concentration. A low notch sensitivity is required in order to reduce the stress concentration factor and prevent cracks from arising as a result. (4) Good weldability. (5) Lower sensitivity to aging. During operation, the tendency for the impact toughness of steel to decrease over time is known as aging. Low sensitivity to aging means that the impact toughness decreases slowly under the same conditions. Low sensitivity to time sensitivity is beneficial for the safe operation of the equipment and for extending its service life.

The boiler drum is subjected to high operating pressure at the saturation temperature of the working fluid. During manufacturing, processes such as sheet rolling, stamping, and welding are involved. The steel used for boiler sheets must possess the following properties: (1) high strength, so as to thin the boiler walls as much as possible, which is beneficial for manufacturing, installation, and operation. (2) Good plasticity and toughness reduce the likelihood of cracks occurring during manufacturing processes such as cylinder sheet rolling and head stamping. (3) Steel plates have low notch sensitivity; the drum contains numerous openings and welds, which lead to stress concentration. A low notch sensitivity is required in order to reduce the stress concentration factor and prevent cracks from arising as a result. (4) Good weldability. (5) Lower sensitivity to aging. During operation, the tendency for the impact toughness of steel to decrease over time is known as aging. Low sensitivity to aging means that the impact toughness decreases slowly under the same conditions. Low sensitivity to time sensitivity is beneficial for the safe operation of the equipment and for extending its service life.

The boiler drum is subjected to high operating pressure at the saturation temperature of the working fluid. During manufacturing, processes such as sheet rolling, stamping, and welding are involved. The steel used for boiler sheets must possess the following properties: (1) high strength, so as to thin the boiler walls as much as possible, which is beneficial for manufacturing, installation, and operation. (2) Good plasticity and toughness reduce the likelihood of cracks occurring during manufacturing processes such as cylinder sheet rolling and head stamping. (3) Steel plates have low notch sensitivity; the drum contains numerous openings and welds, which lead to stress concentration. A low notch sensitivity is required in order to reduce the stress concentration factor and prevent cracks from arising as a result. (4) Good weldability. (5) Lower sensitivity to aging. During operation, the tendency for the impact toughness of steel to decrease over time is known as aging. Low sensitivity to aging means that the impact toughness decreases slowly under the same conditions. Low sensitivity to time sensitivity is beneficial for the safe operation of the equipment and for extending its service life.

The boiler drum is subjected to high operating pressure at the saturation temperature of the working fluid. During manufacturing, processes such as sheet rolling, stamping, and welding are involved. The steel used for boiler sheets must possess the following properties: (1) high strength, so as to thin the boiler walls as much as possible, which is beneficial for manufacturing, installation, and operation. (2) Good plasticity and toughness reduce the likelihood of cracks occurring during manufacturing processes such as cylinder sheet rolling and head stamping. (3) Steel plates have low notch sensitivity; the drum contains numerous openings and welds, which lead to stress concentration. A low notch sensitivity is required in order to reduce the stress concentration factor and prevent cracks from arising as a result. (4) Good weldability. (5) Lower sensitivity to aging. During operation, the tendency for the impact toughness of steel to decrease over time is known as aging. Low sensitivity to aging means that the impact toughness decreases slowly under the same conditions. Low sensitivity to time sensitivity is beneficial for the safe operation of the equipment and for extending its service life.