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.
