The application of nodular cast iron manhole covers has played a very important role in the municipal construction of our city. The appearance of many different types of nodular cast iron manhole covers has provided us with several conveniences. Now let the aluminum electric motor shell supplier introduce to you the characteristics of nodular cast iron manhole covers.
Good toughness. The impact value is detailed with medium carbon steel, which is more than 10 times that of gray iron material.
Strong corrosion resistance. In the water spray corrosion test, the amount of corrosion in the 90-day period is only 1/40 of the steel pipe, which is 1/10 of the gray iron pipe. The service life is 2 times that of gray iron pipes and 5 times that of ordinary steel pipes.
Good plasticity. The elongation is ≥7%, which is similar to that of high-carbon steel, while the elongation of gray iron materials is zero.
high strength. Tensile strength ób≥420MPa, yield strength ós≥300MPa, which is the same as low-carbon steel, and is three times that of gray iron material.
Due to the spheroidal graphite microstructure of nodular cast iron, technical requirements for cast iron manhole covers 1. In terms of weakening vibration capacity, nodular cast iron is better than cast steel, so it is more beneficial to reduce stress. 2. An important reason for choosing ductile iron is that it is cheaper than cast steel. The low cost of nodular cast iron makes this material more popular, more efficient in casting, and less machining costs for nodular cast iron.
The strength of nodular cast iron is comparable to that of cast steel. Ductile iron has a higher yield strength, with a minimum yield strength of 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 ductile iron are better than cast steel.
Ductile iron manhole covers
Features of Ductile iron manhole covers:
1. Beautiful appearance: simple lines. Silver appearance, modern trend.
2. The best drainage: the leakage area is 83.3%, which is more than twice that of cast iron.
3. Anti-theft design: The cover and frame are hinged, which is anti-theft, safe and easy to open.
4. Save investment: big span. Under heavy load, it is cheaper than cast iron and saves the cost of crushing and replacing when stolen.
5. High strength: The strength and toughness are much higher than cast iron, which can be used in large span and heavy load environments such as terminals and airports.
6. Many specifications: meet different environments and loads. Required for span, size and shape.
7, good anti-theft property:
Custom aluminum manhole covers are molded by high temperature molding, because it has no secondary use value and has the characteristics of natural anti-theft.
8, convenient and beautiful:
Products of the same specification weigh only one third of the cast iron cover, which brings great convenience to installation, inspection and maintenance. According to customer requirements, products of various specifications and colors are produced, which can beautify the city even in management.
9, long life:
Not afraid of acid and alkali corrosion, no rust, electrical insulation, wear resistance and weather resistance.
The above are the characteristics and advantages of nodular cast iron manhole covers. Nodular cast iron manhole covers are processed by high temperature and high pressure. Have certain compressive strength and impact and corrosion resistance requirements. Can be widely used in urban road facilities, communications, electricity, telecommunications, natural gas, chemical bases, residential areas and other fields.