Brief introduction
Ductile iron pipe is a kind of cast iron pipe. In terms of quality, the spheroidization grade of cast iron pipe is required to be controlled to 1-3 grades (spheroidization rate>80%), so the mechanical properties of the material itself have been better improved, with the nature of iron and the properties of steel. The metallographic structure of the annealed ductile iron pipe is ferrite plus a small amount of pearlite. It has good mechanical properties, excellent corrosion resistance, good ductility, good sealing effect, easy installation, and is mainly used for water supply, gas transmission, oil transmission, etc. in municipal, industrial and mining enterprises.
A certain amount of spherical graphite is distributed on the ferrite and pearlite matrix. According to the different nominal diameter and requirements for elongation, the proportion of ferrite and pearlite in the matrix structure is different. The proportion of pearlite with small diameter is generally not more than 20%, and that of large diameter is generally controlled at about 25%.
Performance of ductile iron pipe
Ductile iron pipe is a kind of cast iron, which is an alloy of iron, carbon and silicon. Graphite in spheroidal graphite cast iron exists in the form of spheroidal graphite. Generally, the size of graphite is 6-7, and the spheroidization grade of cast pipe is required to be controlled to 1-3 (spheroidization rate ≥ 80%) in terms of quality. Therefore, the mechanical properties of the material itself have been better improved, with the nature of iron and the properties of steel. The metallographic structure of the annealed ductile iron pipe is ferrite plus a small amount of pearlite, and its mechanical properties are good.
Ductile iron pipe is mainly called centrifugal ductile iron pipe. It has the nature of iron, the performance of steel, excellent corrosion resistance, good ductility, good sealing effect, easy installation, and is mainly used for water supply, gas transmission, oil transmission, etc. in municipal, industrial and mining enterprises. It is the first choice of water supply pipes with high cost performance. Compared with PE pipe, the installation time of ductile iron pipe is simpler and faster than PE pipe, and the internal and external bearing pressure is better after installation; From the perspective of airtightness and corrosion resistance, the airtightness of spheroidal graphite pipe after installation is better, and the corrosion resistance can also be improved by a variety of anti-corrosion methods; From the hydraulic performance point of view, because the specification of ductile iron pipe generally refers to the inner diameter, the specification of PE pipe generally refers to the outer diameter, because under the same specification conditions, the ductile iron pipe can achieve greater runoff; From the perspective of comprehensive installation and maintenance costs, the ductile iron pipe has a better cost performance. The inner wall is sprayed with zinc, cement mortar anti-corrosion materials, etc.
Mechanical property of ductile iron pipe
Minimum tensile strength: 420/MPa
Minimum yield strength: 300/MPa, minimum elongation 7%
Standards: GB/T13295-2013, ISO2531-2009
Diameter: DN80-DN2600
Selection suggestions of ductile iron pipe
1. The selection of ductile iron pipes shall be based on the specific conditions of the laying place, and the interface form of straight pipes and fittings shall be selected.
2. The rubber ring is usually made of NBR, SBR, EPDM and other materials.
3. Selection of coating: select the appropriate coating according to the internal and external conditions during use. The existing internal coating is epoxy resin, polyurethane internal and external coating, PE film coating and other new products of ductile iron pipe, and its performance should be understood in detail when selecting.
Advantages and disadvantages of ductile iron pipe
Advantage
Ductile iron pipes are used in medium and low pressure pipe networks (generally used below 6MPa). Ductile iron pipes have safe and reliable operation, low damage rate, convenient and fast construction and maintenance, and excellent corrosion resistance. The newly developed “Yandun” series pipeline can be applied to trenchless construction and widely used in pipeline construction across rivers, roads and buildings. The “Saizin” series pipeline uses the special zinc aluminum alloy external spraying process to improve the corrosion resistance of the pipeline several times, and is widely used in the construction of highly corrosive soil.
Disadvantage
Generally, it is not used in high-pressure pipe network (above 6MPa). Because the pipe body is relatively heavy, machinery must be used during installation. In case of water leakage after the pressure test, all pipes must be dug out, the pipes must be lifted to the height where they can be put into the clamps, and the clamps shall be installed to prevent water leakage.
We JINBAICHENG is one of the renowned manufacturer, exporter, stockist, stock holder and supplier of ductile iron pipe. We have customer from Mexico, Turkey, Pakistan, Oman, Israel, Egypt, Arab,Vietnam, Myanmar, German, etc.
Website: www.sdjbcmetal.com
Email: jinbaichengmetal@gmail.com
Post time: Apr-04-2023