Specialization

The main material used in the company’s manhole covers is ductile iron, which is a structural material with high strength, high toughness and high wear resistance. Nodular graphite is obtained through spheroidization and inoculation treatment, which effectively improves the mechanical properties of cast iron. In particular, the plasticity and toughness are improved, resulting in higher strength than carbon steel. The key process of producing as-cast nodular cast iron is spheroidization. The key factor to ensure the stability of spheroidization quality is to use high-quality raw materials to make manhole covers. As-cast nodular cast iron is a material with strong corrosion resistance, coupled with the use of high-density anti-rust and waterproof paint on the surface of the manhole cover, the manhole cover is more resistant to rust. It is an ideal material to make manhole covers with as-cast ductile iron. At present, more than 98% of developed countries such as Europe, America and Japan use as-cast ductile iron to make manhole covers.