The ductile iron manhole cover has high strength and good toughness, so the ductile iron manhole cover is about 30% lighter than the same type of gray cast iron manhole cover. Nodular cast iron grade adopts QT500-7, molten iron temperature is not lower than 1456℃, rare earth ferrosilicon-magnesium alloy and coke with low sulfur content are added during spheroidizing treatment, and the spheroidizing grade is more than three. The mechanical properties of the ductile cast iron specimens are as follows:
Tensile strength: 500N/MM 2
Elongation rate: 7%
The pressure test damage load of the manhole cover exceeds the industry standard;
The adoption standards are as follows:
CJ/T3012-93 "Cast iron inspection manhole cover" stipulated standard
EN124 "Sluice Cover and Manhole Cover for Driveway Walkway"
The size deviation of the manhole cover and the base meets the domestic standard
Cast iron drainage ditch cover size: Lightweight: 25 tons/m2, campus residential parks, parks, underground parking lots and kitchens where cars and pedestrians pass.
Heavy: 70 tons/m2, factories where cars under 20 tons pass, general roads, art-colored main roads of ductile iron manhole covers, parking lots and streets, etc.
Super heavy: 140 tons/m2, heavy trailers, container forklifts, cranes and airplanes, such as main roads, large parking lots, mines, docks and airports.
Features:
1. Using hot-dip galvanized surface treatment: It has a strong anti-rust force.
2. Advanced inside cover design: the gutter cover made of steel grating is connected with the frame by hinge, which is anti-theft, safe and easy to open
3, the product appearance is beautiful: simple lines, silver appearance, modern ideas
4. Large mesh size and good drainage: The leakage area is 83.3%, which is more than twice that of cast iron.
5. Material saving and investment saving: when large span and heavy load, the price is lower than cast iron; and it can save the cost of replacement of cast iron cover due to theft or crushing.
6. The use of high-strength carbon steel makes the steel grating have 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 docks and airports.
7. Many product varieties: meet the needs of different environments, loads, spans and shapes, and can provide sizes and shapes according to customers.
