It should possess anti-seismic performance features. During the contact between the manhole cover and the well ring, it can provide excellent cushioning, which significantly reduces the vibration force.

Secondly, it is noise-proof, directly acting on the contact interface between the manhole cover and the ring, effectively eliminating noise.

Thirdly, for theft prevention, a square groove protrudes to serve as a fixing function. It can act as a theft deterrent. The concealed lock utilizes a nylon sleeve, eliminating the issue of rust. The ductile iron manhole covers are mainly used for: municipal roads, highways, telecommunications, electricity, water supply, residential areas, schools, and various other parks.

A manhole cover typically weighs around 40 kg. It is generally used in residential or small vehicle lanes, capable of supporting vehicles weighing up to 15 tons, but not suitable for expressways or heavy traffic lanes.

Ductile iron manhole covers have a variety of chemical compositions that are highly stable, including carbon, silicon, manganese, and phosphorus, making them resistant to rust. Additionally, the craftsmanship of the ductile iron manhole covers is excellent; professionals have installed rubber seals at the connection point between the cover and the ground, significantly reducing noise from passing vehicles and preventing the cover from lifting, ensuring the safety of residents. Moreover, the covers offer anti-theft features, as their design is only accessible to professionals, thus ensuring the longevity of the covers and reducing the company's losses.

Excellent toughness. Impact values are detailed and exceed those of medium-carbon steel by 10 times or more.

High corrosion resistance. The spray corrosion test shows that the corrosion amount after 90 days is only 1/40 of steel pipes and 1/10 of gray cast iron pipes. The service life is twice that of gray cast iron pipes and five times that of ordinary steel pipes.

Excellent plasticity. Elongation ≥7%, comparable to high-carbon steel, while gray iron material has zero elongation.

High strength. Tensile strength ób≥420MPa, yield strength ós≥300MPa, similar to low carbon steel, three times that of gray iron material.

Due to the spheroidal graphite microstructure of ductile iron, it outperforms cast steel in vibration reduction capabilities, thus contributing to stress reduction. One significant reason for choosing ductile iron is its lower cost compared to cast steel. The low cost of ductile iron makes it more popular, with high casting efficiency and reduced machining costs. The strength of ductile iron is comparable to that of cast steel. Ductile iron boasts a higher yield strength, with a yield strength as low as 40k, compared to cast steel's 36k. In most municipal applications, such as water, saltwater, and steam, ductile iron's corrosion and oxidation resistance surpasses that of cast steel.