Heat resistant steel castings are a large family, in which pearllet heat resistant steel castings are a common member. The cast is mainly composed of chromium and molybdenum elements, which maintains excellent strength and process performance at high temperatures of 500 to 600℃. They are widely used to manufacture those heat-resistant parts that need to work below 600℃, such as curved furnace floor, gas furnace grate and heat-resistant steel blocks.
In power plants, heat-resistant steel casting products include:
Boiler components: such as grate, hood and burner nozzle. The grate piece needs to withstand the test of high temperature combustion environment, usually using high chromium, nickel content of heat-resistant alloy steel casting, such as ZG40Cr25Ni20Si2 and other materials. The hood requires high temperature resistance, corrosion resistance, wear resistance and good air permeability, commonly used materials such as ZG40Cr26Ni4Mn3NRe. The burner nozzle needs to be stable in high temperature and high pressure environment, usually using high temperature and corrosion resistant alloy cast steel, such as ZG35Cr24Ni7SiN.
Turbine components: such as blades and separator. The blades need good heat resistance, high strength and high toughness, usually cast with martentic or austenitic heat resistant steel, such as ZG1Cr11MoV or ZG0Cr18Ni9. The partition plate requires good heat resistance and mechanical strength, commonly used materials such as ZG20CrMo.
Heat resistant cast iron material
Heat resistant cast iron refers to cast iron used at high temperatures with oxidation or growth resistance. Common hot-resistant cast iron includes medium silicon cast iron, high chromium cast iron and nickel chromium silicon cast iron. High silicon heat resistant cast iron contains 5-6% silicon, the working temperature can be stable at about 850 degrees, but the mechanical performance is low, suitable for the manufacture of heat resistant parts with low force. High-aluminum heat-resistant cast iron can be used at 900 degrees, but the mechanical properties are also poor. The higher the chromium content of high chromium heat resistant cast iron, the higher the heat resistance temperature, when the chromium content is 32-36%, the heat resistance temperature can reach 1150 degrees, and the mechanical performance remains high.
The selection and application of these materials ensure the stability and durability of heat-resistant castings in high temperature environment, and they are widely used in the manufacturing of key components in electric power, metallurgy, chemical industry and other fields.
