Ductile iron water supply pipe

Ductile iron pipes are a new type of metal pipes, and the standard code is GB/T 24596-2021. [1][2] The pressure resistance of ductile iron pipe is above 3MPa, the pipe diameter is 80 ~ 2000 mm, and the effective length is 4 ~ 6 m. It has the advantages of corrosion resistance of cast iron pipe, toughness and strength of steel pipe, impact resistance, vibration resistance and thin pipe wall, and is widely used in urban water supply, drainage and gas transmission projects. [3][4] The manufacturing method of nodular cast iron pipe is to add magnesium or rare earth magnesium alloy nodulizer into molten iron before pouring to spheroidize graphite, and at the same time, add a certain amount of ferrosilicon or calcium silicon alloy as inoculant to promote graphite precipitation. [2]