A ductile iron pipe is made of a kind of cast iron, carbon and silicon alloy, is an iron ore stone blast furnace smelting product. According to the different forms of carbon in pig iron, it can be divided into steel-making pig iron, cast iron and ductile iron and so on. Ductile iron is a kind of high-strength cast iron material developed in the 1950s, and its comprehensive performance is close to steel. Based on its excellent performance, ductile iron has been used to cast some of the high-strength, high-toughness, wear-resistant parts. Ductile iron has rapidly developed into a very extensive cast iron material after gray iron. The so-called "iron substituting steel", mainly refers to ductile iron.
 
Graphite in a ductile iron pipe is in the form of spheroidal graphite. The general graphite size grade is 6-7. In terms of quality, the spheroidization grade of cast iron pipes is required to be 1-3, and the spheroidization rate is 80%, so the mechanical properties of the material itself have been improved. The microstructure of ductile iron pipe after annealing is ferrite with a small amount of pearlite, and the mechanical properties are better.
 
A ductile iron pipe is also called centrifugal ductile iron pipe, whose fittings are magnesium or rare earth magnesium combined with gold pellets before pouring into molten iron, so that the stress concentration of graphite ball is reduced. A ductile iron pipe has advantages such as excellent anti-corrosion performance, ductility, good sealing effect, easy installation. Ductile Iron pipe is mainly used for water, gas, oil in municipal, industrial and mining enterprises projects. A ductile Iron pipe is the first choice for water supply pipes, which is cost-effective. Compared with the PE pipe, from the installation time, the ductile iron pipe is simpler and quicker than PE pipe in installation, and the pressure inside and outside is better after installation. In terms of the airtightness and anti-corrosion performance, the ductile iron pipe has better tightness after installation, and also through a variety of anti-corrosion means to improve the performance. From the hydraulic performance, because the ductile iron pipe specification generally refers to the inner diameter, and PE pipe specification generally refers to the outside diameter, with the same specifications, the ductile iron pipe can achieve greater runoff. From the comprehensive installation and maintenance cost, the ductile iron pipe is superiorly cost-effective.