What are the characteristics of ductile cast iron?

Ductile iron pipes are produced by adding magnesium or a rare-earth-magnesium-based spheroidizing agent to the molten iron before casting, which promotes the formation of spherical graphite structures. This process reduces stress concentrations, resulting in pipe materials that boast high strength, excellent ductility, superior impact resistance, outstanding corrosion resistance, and exceptional sealing performance. Additionally, the inner surface is lined with cement mortar, enhancing the water-carrying environment within the pipeline, boosting water delivery efficiency, and significantly lowering energy consumption. At the pipe ends, flexible joints are used, allowing the pipes themselves to stretch considerably—giving them remarkable flexibility. This flexibility enables the pipes to work synergistically with the surrounding soil in buried pipelines, effectively improving the overall stress distribution and, consequently, increasing the reliability of the entire pipeline network. As a result, ductile iron pipes are now commonly employed as main pipelines in China's water supply industry.

　　The Folded Surface Quality of Ductile Cast Iron ：

　　1. The inner and outer surfaces of ductile iron pipe fittings must be smooth, free from any obvious defects that could impede their use, such as cracks, cold shuts, or misaligned joints. Localized defects that reduce wall thickness are permitted, provided their depth does not exceed (20.05T) mm, where T represents the wall thickness of the pipe body.

　　2. The spare flange for ductile iron pipe fittings must have a clear outline, and no casting defects that could affect its functionality are allowed.

　　3. With the buyer's approval, minor defects that do not affect usability may be repaired; however, the repaired fittings Needed Perform the hydrostatic or air-tightness test again.

　　The Folded Coating of Ductile Cast Iron:

　　1. The inner and outer surfaces of ductile iron pipe fittings can be cleaned using paint or other anti-corrosion materials. If there are special requirements, please consult with the supplier and the buyer.

　　2. When supplying water using ductile iron pipe fittings, the sanitary conditions must comply with relevant regulations set forth by the health authorities.

　　3. Before coating, the inside and outside of the fittings should be cleaned thoroughly. After coating, both the inner and outer surfaces must be smooth, with a coating that is even, firmly adhered, and free from abnormalities caused by environmental changes.

　　The advantages of ductile cast iron:

　　1. Since ductile iron pipe fittings feature flexible joints, construction operations are convenient, boosting efficiency, improving working conditions, and reducing costs. Moreover, most connections use rubber gaskets, making installation easy, shortening the project timeline, and lowering overall construction expenses.

　　2. Ductile iron pipe fittings offer numerous advantages, including the ability to withstand high water pressure, resist external loads, adapt to varying geological conditions, exhibit high strength and excellent toughness, provide outstanding corrosion resistance, feature convenient flexible joint installation, demonstrate strong seismic performance, and significantly reduce labor intensity. These features make them ideal for applications in areas with poor soil conditions or where pipelines need to cross roads—eliminating the need for additional processing of steel pipes. With their exceptional corrosion resistance, they are also well-suited for coastal regions and saline-alkali environments. Widely used in underground pipeline projects, these fittings truly shine in large-scale pipeline installation projects, highlighting their ease of installation and low labor requirements.

3. Ductile iron pipe fittings offer excellent sealing performance, minimizing leakage and helping to reduce pipeline network leakage rates as well as lowering daily maintenance costs.

These are some key points about ductile iron. I hope everyone can carefully study and understand the relevant knowledge, enabling you to choose the product that best meets your needs.