Ductile iron pipes have three times the tensile strength of gray iron pipes; their hydrostatic test is twice as strong as that of gray iron pipes; ductile iron pipes have a higher elongation rate compared to gray iron pipes, which are brittle materials with an elongation rate of 0. The mechanical properties of ductile iron pipes are superior to those of welded steel pipes. They can withstand higher pressures and are easier to lay, inspect, and protect. Additionally, ductile iron pipes have better corrosion resistance than welded steel pipes, with an underground service life that is over twice as long.

Ductile iron pipes are produced by adding rare earth elements and other materials to the molten iron after it has been shaped from the raw material, which purifies the iron and promotes graphitization. This enhances the pipe's compressive strength, hardness, ductility, and elongation, improving its pressure resistance and impact resistance. Ensuring the quality of the ductile iron pipes, they can withstand harsh environments and have a lifespan several times longer than that of gray cast iron pipes. The range of ductile iron pipe fittings includes socket short pipes, double socket sleeves, socket short pipes, double socket elbows, single socket T-pieces, triple socket T-pieces, double socket cones, double socket 90° elbows, double socket 45° elbows, full socket T-pieces, socket T-pieces, and double socket T-pieces.

Ductile iron pipes are essentially spheroidal cast iron pipes, thus their inherent mechanical properties have been significantly enhanced, combining the properties of iron with the functions of steel. After annealing, the microstructure of spheroidal cast iron pipes consists of ferrite with a small amount of spheroidite, exhibiting excellent mechanical properties, hence the alternate name of cast iron pipes. Spheroidal cast iron pipes are an alloy of iron, carbon, and silicon, with the graphite existing in a spherical form. The K8 priced spheroidal cast iron drainage pipes possess the essence of cast iron. The particle size of the graphite is generally 6-7 grades, and the quality requirement for the spheroidizing grade of the cast pipes should be controlled at 1-3 grades (spheroidizing rate ≥80%), thereby further improving the material's mechanical properties. Spheroidal cast iron pipes are a type of cast iron that retains the properties of iron and the functions of steel. After annealing, they are arranged as ferrite with a small amount of spheroidite, demonstrating good mechanical properties.