Ductile Iron Square Manhole Cover

Ductile iron manhole cover

Because of the high strength and toughness of nodular cast iron, nodular cast manhole cover is about 30% lighter than that of gray cast iron of the same type. The nodular cast iron brand is qt500-7, the hot metal discharge temperature is not lower than 1456℃, and the rare earth ferrosilicon magnesium alloy and the coke with low sulfur content are added during the spheroidal treatment, and the spheroidal grade is above 3.

Features:

1. Good toughness. Impact value is similar to medium carbon steel, 10 times more than gray iron.
2. Strong corrosion resistance. Water spray corrosion test, 90 days of corrosion of steel tube is only 1/40, is 1/10 of the gray iron pipe. Service life is 2 times of gray iron pipe, 5 times of ordinary steel pipe.
3. Good plasticity. Elongation ≥7%, similar to high carbon steel, and gray iron material elongation is zero.
4. High intensity. Tensile strength ob ≥420MPa, yield strength OS ≥300MPa, the same as low carbon steel, is three times the gray iron material.