Due to the spheroidal graphite microstructure of nodular cast iron, nodular cast iron is better than cast steel in reducing vibration, so it is more conducive to reducing stress. An important reason for choosing nodular cast iron is that the cost of nodular cast iron is lower than that of cast steel. The low cost of nodular cast iron makes this material more popular, higher casting efficiency and less machining cost of nodular cast iron. The strength of nodular cast iron is comparable to that of cast steel. Nodular cast iron has higher yield strength, and its yield strength * is as low as 40K, while the yield strength of cast steel is only 36K. In most municipal applications, such as water, salt water, steam, etc., the corrosion resistance and oxidation resistance of nodular cast iron are higher than that of cast steel.
He is strong in earthquake resistance and corrosion resistance. In the water spray corrosion test, the corrosion amount in 90 days is only 1 / 40 of that of gray cast iron well cover and 1 / 10 of that of gray nodular graphite well cover. The service life of well cover made of Henan gray iron and cast iron is 5 times that of ordinary well cover. The service life of nodular cast iron manhole cover will be prolonged only if we use it reasonably and maintain it patiently.
(6) Rare earth magnesium nodular cast iron. In terms of high strength and low alloy nodular cast iron, in addition to copper and molybdenum, nickel and niobium were also studied. Some units in China have done a lot of systematic work in the production of vanadium titanium alloy nodular cast iron from * * vanadium titanium pig iron. Although the properties of medium manganese nodular cast iron are not stable enough, remarkable economic benefits have been obtained in systematic research and production application. Main application fields of nodular well covers: municipal roads, highways, communications, electric power, tap water, residential areas, schools and other parks.
Nodular well covers can decorate urban roads. There are many nodular well covers on the road. The patterns and words on the cast-iron well covers are different, and the purpose of the well covers is also different. Here is a brief introduction to the world under the bottom of these well covers. 1. Well covers of drainage engineering: for rainwater and sewage pipelines. 2. Well cover of water supply engineering: used in tap water, fire engineering, etc. 3. Well cover of heating engineering: applied to thermal arm line. 4. Well cover of power supply engineering: it is applied to power supply cable, telecommunication engineering, telephone and communication cable pipeline. 5. Garden engineering well cover: used for supporting comprehensive pipelines. 6. Gas engineering well cover: used in gas engineering, * * gas pipeline, etc. 7. Street lamp engineering well cover: used for power supply, lighting and cable pipelines.
The above is the detailed introduction of Shandong ductile iron manhole cover. I hope it will be helpful to you If you have any questions, please contact us We will provide you with professional service http://www.jnwszy.com